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Viruses & Microbes: 620 3D models

Viruses, ~330 bacteria and archaea (cells, Gram stains, colonies on 40 culture media), ~110 fungi, parasites and protists (real sizes 20 nm–200 µm). Each one is a ready-made 3D model you can turn, recolour and place in a figure — open BioDioRama and type its name in the Library search.

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Viruses 16

Coronavirus (SARS-CoV-2) — A round, enveloped RNA virus crowned with spike proteins — the virus behind COVID-19. Cut it open to see the coiled RNA genome. (≈ 100 nm)
Influenza virus — The flu virus: hemagglutinin (H) and neuraminidase (N) spikes on the envelope, eight RNA segments inside. (≈ 100 nm)
HIV — Human immunodeficiency virus: Env spikes on the envelope and a cone-shaped capsid holding two RNA copies and the enzymes to copy them. (≈ 120 nm)
Bacteriophage T4 — A virus that infects bacteria: an icosahedral head, a contractile tail and six leg-like tail fibres. (≈ 200 nm tall)
Adenovirus — A naked icosahedral DNA virus with a fibre sticking out of each of its 12 corners — a common cold virus and a vaccine vector. (≈ 90 nm)
Icosahedral virus — The 20-sided protein shell many small viruses use (polio, norovirus, HPV). Adjust detail and capsomer shape. (≈ 30–60 nm)
Tobacco mosaic virus — A rod-shaped plant virus: coat proteins stacked in a helix around a single RNA strand. (≈ 300 nm long)
Ebola virus — A long, thread-like filovirus that often curls into a "6" or shepherd's crook. (≈ 80 nm wide, ~1 µm long)
Rabies virus — A bullet-shaped virus covered in glycoprotein spikes. (≈ 180 × 75 nm)
Icosahedral virus (hexagonal capsomers) — A small icosahedral capsid drawn with flat hexagonal capsomers. (≈ 30–60 nm)
Ebola virus (U-shaped) — A filovirus bent into a U. (≈ 80 nm wide, ~1 µm long)
Filovirus (straight) — A straight filovirus particle, like Marburg virus. (≈ 80 nm wide, ~1 µm long)
SARS-CoV-2 (cut open) — SARS-CoV-2 cut open to show its coiled RNA genome and nucleocapsid. (≈ 100 nm)
Bacteriophage injecting its DNA — A T4 phage with its tail contracted, injecting DNA into a bacterium. (≈ 200 nm tall)
HIV (closed) — The intact HIV particle with Env spikes. (≈ 120 nm)
Influenza virus (closed) — The intact flu virus covered in HA and NA spikes. (≈ 100 nm)

Protists 17

Malaria parasite in a red cell — A Plasmodium "ring stage" parasite living inside a red blood cell. (cell ≈ 7 µm)
Paramecium — A slipper-shaped single cell covered in beating cilia, with two nuclei and star-shaped contractile vacuoles. (≈ 200 µm)
Amoeba — A shape-shifting cell that crawls and eats by pushing out pseudopods. (≈ 250–750 µm)
Euglena — A green swimmer with a whip-like flagellum, a red eyespot and chloroplasts. (≈ 50 µm)
Chlamydomonas — A single-celled green alga with two flagella, a cup-shaped chloroplast and an eyespot. (≈ 10 µm)
Diatom — A single-celled alga living in a patterned glass (silica) shell. (≈ 20–200 µm)
Volvox colony — A hollow green ball of hundreds of flagellated cells in a gel matrix, carrying daughter colonies inside — a model for the origin of multicellularity. (≈ 0.5 mm)
Spirogyra — A filamentous green alga whose cells each hold ribbon-shaped chloroplasts wound in a spiral, studded with pyrenoids. (cells ≈ 10–100 µm)
Trypanosoma brucei — The parasite of sleeping sickness among red blood cells: a slender cell with an undulating membrane, a flagellum and a kinetoplast. (≈ 20–30 µm)
Giardia lamblia — The "face-like" gut parasite: two nuclei, a ventral sucking disc, median bodies and four pairs of flagella. (≈ 12–15 µm)
Toxoplasma gondii — A crescent-shaped apicomplexan tachyzoite with its apical complex (conoid, rhoptries, micronemes), apicoplast and nucleus. (≈ 2 × 6 µm)
Foraminifera — A marine amoeboid protist with a spiral, chambered calcite shell and a web of thread-like reticulopodia. (≈ 0.1–1 mm)
Radiolarian — A planktonic protist with a glassy silica lattice skeleton, radial spines and symbiotic algae around its central capsule. (≈ 0.1–0.2 mm)
Dinoflagellate — An armoured alga with cellulose plates, a girdle groove holding the transverse flagellum and a trailing longitudinal flagellum; causes red tides. (≈ 20–100 µm)
Vorticella — Bell-shaped ciliates on spring-like contractile stalks, sweeping food in with a crown of cilia. (≈ 50–150 µm)
Stentor — A giant trumpet-shaped ciliate with blue pigment stripes, a spiral crown of membranelles and a beaded macronucleus. (≈ 1–2 mm)
Pennate diatom — A boat-shaped diatom in its glass shell. (≈ 20–200 µm)

Fungi 5

Mold (Penicillium) — Fungal threads (hyphae) with brush-like stalks releasing chains of spores. (stalks ≈ 100 µm)
Budding yeast (S. cerevisiae), cut open — Baker's yeast — a model eukaryote — budding: cell wall, nucleus, vacuole, mitochondria and chitin bud scars. (≈ 5 µm)
Candida albicans — The commonest fungal pathogen, switching between round yeast cells, pinched pseudohyphae and true septate hyphae. (yeast ≈ 4 µm)
Aspergillus conidiophore — The spore-making head of Aspergillus: a stalk swelling into a vesicle covered in phialides that bud chains of conidia. (≈ 0.3 mm)
Fungal mycelium — Spores germinating on agar into a branching network of septate hyphae. (hyphae ≈ 2–10 µm wide)

Tiny animals 2

Tardigrade (water bear) — A chubby eight-legged micro-animal that can survive almost anything. (≈ 0.5 mm)
C. elegans (nematode) — The famous lab roundworm; see-through so you can show its gut, pharynx and eggs. (≈ 1 mm)

Bacteria 1

Biofilm — Bacteria living together in towers of slimy matrix on a surface. (≈ 10–100 µm tall)

Viruses · Picornaviridae 2

Poliovirus — A tiny non-enveloped RNA virus with a canyon-studded T=pseudo3 capsid; the target of the global eradication campaign. Looks the same as: Rhinovirus (common cold), Enterovirus A71, Hepatitis A virus, Coxsackievirus A16, Coxsackievirus B3, Enterovirus D68 and 4 more. (30 nm)
Foot-and-mouth disease virus — A smooth picornavirus causing a major livestock disease. Looks the same as: Cowpea mosaic virus. (25 nm)

Viruses · Caliciviridae 1

Norovirus — The "winter vomiting bug": a T=3 capsid with 90 protruding arch-like dimers. Looks the same as: Sapovirus, Feline calicivirus, Rabbit haemorrhagic disease virus. (38 nm)

Viruses · Papillomaviridae 3

Human papillomavirus (HPV) — A T=7 capsid of 72 L1 pentamers around circular DNA; the cause of cervical cancer and target of HPV vaccines. (55 nm)
HPV L1 virus-like particle (vaccine) — An empty HPV capsid made of L1 protein — the antigen of the Gardasil and Cervarix vaccines. (55 nm)
HPV16 — High-risk papillomavirus behind most cervical cancers. Looks the same as: HPV18, HPV6. (55 nm)

Viruses · Polyomaviridae 2

Polyomavirus (SV40 / JC) — A small T=7 DNA virus; SV40 gave biology the nuclear-localisation signal and promoter. (45 nm)
BK polyomavirus — Reactivates in kidney transplant recipients. Looks the same as: Merkel cell polyomavirus. (45 nm)

Viruses · Parvoviridae 4

Adeno-associated virus (AAV) — The 25 nm T=1 capsid used as the leading gene-therapy vector (e.g. Zolgensma). (25 nm)
Parvovirus B19 — A tiny T=1 DNA virus causing fifth disease; infects red-cell precursors. (23 nm)
Canine parvovirus — Tiny T=1 capsid; severe enteritis in puppies. Looks the same as: Human bocavirus. (26 nm)
Minute virus of mice — Model rodent parvovirus. Looks the same as: AAV2 vector, AAV8 vector, AAV9 vector, AAV5 vector, AAV-PHP.eB vector. (25 nm)

Viruses · Adenoviridae 2

Adenovirus 5 — A 90 nm T=25 DNA virus with fibres at its 12 vertices; a vaccine and gene-therapy vector. (90 nm)
Adenovirus 26 vector — Vaccine vector (Ad26.COV2.S, Ebola vaccine). Looks the same as: ChAdOx1 vector, Adenovirus 2, Adenovirus 35. (90 nm)

Viruses · Hepadnaviridae 2

Hepatitis B virus (Dane particle) — An enveloped 42 nm virus with an icosahedral core around partly double-stranded DNA. (42 nm)
Hepatitis B surface-antigen particle (vaccine) — A 22 nm lipoprotein particle of HBsAg — the first recombinant vaccine. (22 nm)

Viruses · Herpesviridae 6

Herpes simplex virus 1 — A T=16 capsid of 162 capsomers inside a tegument and spiky envelope; causes cold sores. (200 nm)
Varicella-zoster virus — The herpesvirus of chickenpox and shingles. (180 nm)
Cytomegalovirus — The largest human herpesvirus; a major cause of congenital infection. (230 nm)
Epstein–Barr virus — The herpesvirus of glandular fever, linked to lymphomas and multiple sclerosis. (180 nm)
Herpes simplex virus 2 — Genital herpes. Looks the same as: T-VEC (talimogene laherparepvec). (200 nm)
Human herpesvirus 6 — Roseola (sixth disease) of infants. Looks the same as: Kaposi sarcoma herpesvirus (HHV-8), Pseudorabies virus. (200 nm)

Viruses · Flaviviridae 4

Dengue virus — A smooth 50 nm flavivirus tiled with 180 envelope proteins in herringbone rafts; spread by mosquitoes. Looks the same as: Zika virus, Yellow fever virus, West Nile virus. (50 nm)
Hepatitis C virus — A pleomorphic enveloped virus coated in lipoprotein; now curable with antivirals. (55 nm)
Japanese encephalitis virus — Mosquito-borne encephalitis in Asia. Looks the same as: Tick-borne encephalitis virus, Usutu virus. (50 nm)
Bovine viral diarrhoea virus — Pestivirus of cattle. (50 nm)

Viruses · Togaviridae 2

Chikungunya virus — An alphavirus with 80 envelope-protein spikes in a T=4 lattice; causes severe joint pain. (70 nm)
Sindbis virus — Model alphavirus with a T=4 glycoprotein shell. Looks the same as: Semliki Forest virus, Ross River virus, Venezuelan equine encephalitis virus, Mayaro virus. (70 nm)

Viruses · Matonaviridae 1

Rubella virus — The virus of German measles, dangerous in pregnancy. (60 nm)

Viruses · Paramyxoviridae 4

Measles virus — A large, pleomorphic enveloped virus with H and F spikes — one of the most contagious viruses. (150–300 nm)
Mumps virus — A paramyxovirus that swells the salivary glands. (150 nm)
Nipah virus — A deadly bat-borne henipavirus. (150 nm)
Human parainfluenza virus 3 — Bronchiolitis and croup. Looks the same as: Hendra virus, Newcastle disease virus, Sendai virus, Canine distemper virus, Peste des petits ruminants virus. (200 nm)

Viruses · Pneumoviridae 2

Respiratory syncytial virus — A major cause of infant bronchiolitis; its F protein is the target of new vaccines and antibodies. (150 nm)
Human metapneumovirus — RSV-like respiratory virus of children and older adults. (150 nm)

Viruses · Orthomyxoviridae 3

Influenza B virus — A human seasonal flu virus with HA and NA spikes and eight RNA segments. Looks the same as: Avian influenza H5N1. (100 nm)
Influenza A H1N1 (1918) — The "Spanish flu" pandemic virus. Looks the same as: Influenza A H1N1pdm09, Influenza A H3N2, Avian influenza H7N9. (100 nm)
Influenza C virus — Mild flu virus with a single HEF glycoprotein in hexagonal arrays. (100 nm)

Viruses · Coronaviridae 4

MERS coronavirus — A camel-borne coronavirus with club-shaped spikes. (120 nm)
SARS coronavirus (2003) — The coronavirus of the 2002–2004 SARS outbreak. (100 nm)
Human coronavirus OC43 — A common-cold coronavirus with both spike and hemagglutinin-esterase fringes. (110 nm)
Human coronavirus 229E — Seasonal common-cold coronavirus. Looks the same as: Human coronavirus NL63, Human coronavirus HKU1, Porcine epidemic diarrhoea virus, Feline infectious peritonitis virus, Mouse hepatitis virus, Infectious bronchitis virus. (120 nm)

Viruses · Sedoreoviridae 2

Rotavirus — A triple-layered, wheel-like particle with VP4 spikes and 11 dsRNA segments; the main cause of infant diarrhoea. (75 nm)
Bluetongue virus — Midge-borne orbivirus of sheep with a double-layered capsid. (80 nm)

Viruses · Spinareoviridae 1

Reovirus — A double-capsid dsRNA virus with 10 genome segments. (85 nm)

Viruses · Retroviridae 5

HIV-2 — A less pathogenic relative of HIV-1, common in West Africa. (110 nm)
HTLV-1 — A retrovirus causing adult T-cell leukaemia. (100 nm)
Lentiviral vector — A VSV-G-pseudotyped HIV-based vector used to make CAR-T cells and stably modify cells. (100 nm)
HIV-1 — The AIDS virus: an enveloped lentivirus with sparse Env spikes and a conical capsid. Looks the same as: Simian immunodeficiency virus, Feline immunodeficiency virus. (120 nm)
Murine leukaemia virus (γ-retroviral vector) — Gammaretrovirus behind the first generation of gene-therapy vectors. Looks the same as: Rous sarcoma virus, Mouse mammary tumour virus, Feline leukaemia virus. (100 nm)

Viruses · Rhabdoviridae 2

Vesicular stomatitis virus — A bullet-shaped rhabdovirus whose G protein pseudotypes lentiviral vectors; an Ebola vaccine backbone. (70 × 180 nm)
Rabies virus — Bullet-shaped lyssavirus spread by bites; almost always fatal once symptoms start. Looks the same as: Vesicular stomatitis virus (bullet). (75 × 180 nm)

Viruses · Arenaviridae 2

Lassa virus — A rodent-borne arenavirus whose particles contain sandy host ribosomes. (110 nm)
Lymphocytic choriomeningitis virus — Mouse arenavirus — the classic model of T-cell immunity and exhaustion. Looks the same as: Junín virus. (110 nm)

Viruses · Hantaviridae 1

Hantavirus — A rodent-borne virus with a square-lattice glycoprotein surface; causes haemorrhagic fever. (120 nm)

Viruses · Poxviridae 3

Vaccinia virus — The brick-shaped poxvirus used to eradicate smallpox. Looks the same as: Mpox virus, Variola (smallpox) virus. (250 × 350 nm)
Modified vaccinia Ankara (MVA) — Attenuated, non-replicating pox vector and mpox vaccine. Looks the same as: Cowpox virus, Molluscum contagiosum virus, Myxoma virus. (250 nm)
Orf virus — Parapoxvirus of sheep with a criss-cross surface; infects farmers. (260 nm)

Viruses · Mimiviridae 2

Mimivirus (giant virus) — A giant amoeba virus — 500 nm with a coat of fibrils and a starfish-shaped "stargate" portal. (500 nm)
Megavirus chilensis — Giant amoeba virus with > 1 000 genes. Looks the same as: Tupanvirus, Mamavirus with Sputnik virophage. (700 nm)

Viruses · Microviridae 1

Bacteriophage ΦX174 — A tiny T=1 phage with spikes at its vertices; the first DNA genome ever sequenced. (25 nm)

Viruses · Fiersviridae 3

Bacteriophage MS2 — A T=3 RNA phage widely used to package RNA and as a virus-like-particle scaffold. Looks the same as: Turnip yellow mosaic virus, Brome mosaic virus. (27 nm)
Bacteriophage Qβ VLP — An RNA phage capsid used as a virus-like-particle vaccine carrier. (28 nm)
Bacteriophage PP7 — RNA phage whose coat protein is used to tag RNAs in live cells. (26 nm)

Viruses · Bromoviridae 1

Cowpea chlorotic mottle virus — A T=3 plant virus that self-assembles around RNA or nanoparticles in vitro. (28 nm)

Bacteria · Gram-negative rods 14

Escherichia coli — The best-studied organism: a gut rod with peritrichous flagella and pili; workhorse of molecular biology. (≈ 1–5 µm)
Salmonella enterica — A food-borne pathogen that injects effectors through a type-III secretion system. (≈ 1–5 µm)
Shigella flexneri — A non-motile cause of dysentery that spreads cell to cell with actin tails. (≈ 1–5 µm)
Klebsiella pneumoniae — A heavily encapsulated, often multidrug-resistant hospital pathogen. (≈ 1–5 µm)
Pseudomonas aeruginosa — An opportunistic biofilm former with one polar flagellum; infects burns and CF lungs. (≈ 1–5 µm)
Acinetobacter baumannii — A short, stubby, highly drug-resistant ICU pathogen. (≈ 1–5 µm)
Proteus mirabilis — A swarming, urease-making rod behind kidney stones. (≈ 1–5 µm)
Yersinia pestis — The plague bacterium, spread by fleas. (≈ 1–5 µm)
Legionella pneumophila — A water-borne rod that lives inside amoebae and macrophages; causes Legionnaires' disease. (≈ 1–5 µm)
Bordetella pertussis — The cause of whooping cough. (≈ 1–5 µm)
Haemophilus influenzae — A small coccobacillus; type b caused meningitis before the Hib vaccine. (≈ 1–5 µm)
Agrobacterium tumefaciens — A plant pathogen that transfers DNA into plants — the tool for making GM crops. (≈ 1–5 µm)
Rhizobium leguminosarum — A nitrogen-fixing symbiont of legume root nodules. (≈ 1–5 µm)
Synechococcus (cyanobacterium) — A tiny photosynthetic ocean cyanobacterium. (≈ 1–5 µm)

Bacteria · Curved & spiral bacteria 20

Vibrio cholerae — The comma-shaped cause of cholera, with a single sheathed polar flagellum. (≈ 1–5 µm)
Campylobacter jejuni — A curved food-borne pathogen with flagella at both poles. (≈ 1–5 µm)
Helicobacter pylori — A helical stomach bacterium with a tuft of sheathed flagella; causes ulcers (Nobel Prize 2005). (≈ 1–5 µm)
Caulobacter crescentus — A crescent-shaped model for the bacterial cell cycle and asymmetric division. (≈ 1–5 µm)
Treponema pallidum — The thin corkscrew spirochete of syphilis. (≈ 5–20 µm)
Borrelia burgdorferi — The tick-borne spirochete of Lyme disease. (≈ 5–20 µm)
Leptospira interrogans — A hooked spirochete spread in rat urine; causes leptospirosis. (≈ 5–20 µm)
Spirillum volutans — A large, rigid spiral bacterium with flagellar tufts. (≈ 5–20 µm)
Campylobacter jejuni — The commonest bacterial cause of food poisoning. Curved, gull-wing Gram-negative rods with a flagellum at each pole; microaerophilic. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on CCDA (Campylobacter) agar, Columbia blood agar (microaerobic). (≈ 1.91 × 0.41 µm)
Campylobacter coli — Curved, gull-wing Gram-negative rods with a flagellum at each pole; microaerophilic. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on CCDA (Campylobacter) agar, Columbia blood agar (microaerobic). (≈ 1.97 × 0.37 µm)
Campylobacter fetus — Curved, gull-wing Gram-negative rods with a flagellum at each pole; microaerophilic. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on CCDA (Campylobacter) agar, Columbia blood agar (microaerobic). (≈ 2.24 × 0.38 µm)
Helicobacter pylori — Gastritis, ulcers and gastric cancer. Helical Gram-negative rods with a tuft of sheathed flagella; urease positive. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on CCDA (Campylobacter) agar, Columbia blood agar (microaerobic). (≈ 2.89 × 0.5 µm)
Helicobacter hepaticus — Mouse model of colitis. Helical Gram-negative rods with a tuft of sheathed flagella; urease positive. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on CCDA (Campylobacter) agar, Columbia blood agar (microaerobic). (≈ 2.88 × 0.46 µm)
Arcobacter butzleri — Aerotolerant campylobacter relative from food and water. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on CCDA (Campylobacter) agar, Columbia blood agar (microaerobic). (≈ 2.2 × 0.4 µm)
Treponema pallidum — Syphilis. Thin, tightly coiled spirochete with internal (axial) flagella. Choose the view: the cells in 3-D, a stained smear (dark-field microscopy) or colonies on agar. (≈ 9.37 × 0.16 µm)
Treponema denticola — Periodontitis. Thin, tightly coiled spirochete with internal (axial) flagella. Choose the view: the cells in 3-D, a stained smear (dark-field microscopy) or colonies on agar. (≈ 10.78 × 0.14 µm)
Borrelia burgdorferi — Lyme disease. Loosely coiled tick-borne spirochete. Choose the view: the cells in 3-D, a stained smear (dark-field microscopy) or colonies on agar. (≈ 16.95 × 0.23 µm)
Borrelia recurrentis — Louse-borne relapsing fever. Loosely coiled tick-borne spirochete. Choose the view: the cells in 3-D, a stained smear (dark-field microscopy) or colonies on agar. (≈ 14.9 × 0.23 µm)
Leptospira interrogans — Leptospirosis (Weil's disease). Tightly coiled spirochete with hooked ends. Choose the view: the cells in 3-D, a stained smear (dark-field microscopy) or colonies on agar. (≈ 12.16 × 0.12 µm)
Leptospira biflexa — Tightly coiled spirochete with hooked ends. Choose the view: the cells in 3-D, a stained smear (dark-field microscopy) or colonies on agar. (≈ 11.86 × 0.11 µm)

Bacteria · Gram-positive rods 19

Bacillus subtilis — The Gram-positive model organism; forms tough endospores. (≈ 1–5 µm)
Bacillus anthracis — The large encapsulated rod of anthrax. (≈ 1–5 µm)
Clostridioides difficile — An anaerobic spore former behind antibiotic-associated colitis. (≈ 1–5 µm)
Clostridium botulinum — The anaerobe that makes botulinum toxin. (≈ 1–5 µm)
Listeria monocytogenes — A food-borne rod that rides actin comet tails inside cells. (≈ 1–5 µm)
Lactobacillus acidophilus — A long rod of the healthy gut and vagina; used in probiotics and yogurt. (≈ 1–5 µm)
Bifidobacterium longum — A branching infant-gut commensal used as a probiotic. (≈ 1–5 µm)
Corynebacterium diphtheriae — The club-shaped cause of diphtheria. (≈ 1–5 µm)
Cutibacterium acnes — Club-shaped skin anaerobe (formerly Propionibacterium) linked to acne. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Anaerobic blood agar, MRS agar. (≈ 1.58 × 0.66 µm)
Listeria monocytogenes — Listeriosis from soft cheese and deli meat. Short Gram-positive rods with tumbling motility at 25 °C; grow in the cold. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), PALCAM agar, ALOA (Listeria chromogenic) agar. (≈ 1.45 × 0.49 µm)
Listeria innocua — Short Gram-positive rods with tumbling motility at 25 °C; grow in the cold. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), PALCAM agar, ALOA (Listeria chromogenic) agar. (≈ 1.43 × 0.52 µm)
Listeria ivanovii — Short Gram-positive rods with tumbling motility at 25 °C; grow in the cold. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), PALCAM agar, ALOA (Listeria chromogenic) agar. (≈ 1.45 × 0.46 µm)
Erysipelothrix rhusiopathiae — Thin Gram-positive rod of pig erysipelas. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), PALCAM agar, ALOA (Listeria chromogenic) agar. (≈ 1.9 × 0.39 µm)
Gardnerella vaginalis — Gram-variable coccobacillus of bacterial vaginosis ("clue cells"). Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Chocolate agar, Blood agar (5% sheep). (≈ 1.37 × 0.45 µm)
Corynebacterium diphtheriae — Diphtheria toxin; black colonies on tellurite agar. Club-shaped Gram-positive rods arranged like Chinese letters. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Tellurite blood agar, Blood agar (5% sheep). (≈ 2.01 × 0.62 µm)
Corynebacterium glutamicum — Industrial producer of glutamate and lysine. Club-shaped Gram-positive rods arranged like Chinese letters. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Tellurite blood agar, Blood agar (5% sheep). (≈ 1.86 × 0.58 µm)
Corynebacterium jeikeium — Club-shaped Gram-positive rods arranged like Chinese letters. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Tellurite blood agar, Blood agar (5% sheep). (≈ 2.25 × 0.64 µm)
Corynebacterium striatum — Club-shaped Gram-positive rods arranged like Chinese letters. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Tellurite blood agar, Blood agar (5% sheep). (≈ 2.23 × 0.64 µm)
Corynebacterium ulcerans — Club-shaped Gram-positive rods arranged like Chinese letters. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Tellurite blood agar, Blood agar (5% sheep). (≈ 2.14 × 0.63 µm)

Bacteria · Acid-fast & atypical bacteria 3

Mycobacterium tuberculosis — The slow-growing, waxy-walled cause of tuberculosis. (≈ 1–5 µm)
Mycobacterium leprae — The cause of leprosy, which grows only in cool body parts. (≈ 1–5 µm)
Streptomyces coelicolor — A soil bacterium that grows like a fungus and makes most natural antibiotics. (≈ 1–5 µm)

Bacteria · Cocci 10

Staphylococcus aureus — Grape-like clusters; the cause of skin infections, sepsis and MRSA. (≈ 1 µm each)
Staphylococcus epidermidis — A skin commensal that forms biofilms on implants and catheters. (≈ 1 µm each)
Streptococcus pyogenes — Group A strep: chains of cocci causing sore throat and necrotising fasciitis. (≈ 1 µm each)
Streptococcus pneumoniae — Lancet-shaped encapsulated diplococci; the leading cause of pneumonia. (≈ 1 µm each)
Streptococcus mutans — The tooth-decay bacterium that makes sticky glucans and acid. (≈ 1 µm each)
Enterococcus faecalis — A hardy gut coccus behind hospital infections and VRE. (≈ 1 µm each)
Neisseria meningitidis — Kidney-bean diplococci causing meningococcal meningitis. (≈ 1 µm each)
Neisseria gonorrhoeae — The diplococcus of gonorrhoea, increasingly drug-resistant. (≈ 1 µm each)
Micrococcus luteus — Yellow cocci in tetrads, common on skin. (≈ 1 µm each)
Sarcina ventriculi — Cuboidal packets of eight cocci found in the stomach. (≈ 1 µm each)

Viruses · Astroviridae 1

Human astrovirus — Star-like surface; gastroenteritis in children. (30 nm)

Viruses · Hepeviridae 1

Hepatitis E virus — Water-borne hepatitis; severe in pregnancy. (32 nm)

Viruses · Circoviridae 1

Porcine circovirus 2 — The smallest animal viruses (17 nm, T=1). Looks the same as: Banana bunchy top virus. (17 nm)

Viruses · Phenuiviridae 1

Rift Valley fever virus — Mosquito-borne virus of livestock and people with a T=12 glycoprotein shell. Looks the same as: Crimean–Congo haemorrhagic fever virus, SFTS virus (Dabie bandavirus), Oropouche virus. (100 nm)

Viruses · Tectiviridae 1

Bacteriophage PRD1 — Phage with an internal membrane under a T=25 capsid. (65 nm)

Viruses · Tombusviridae 1

Tomato bushy stunt virus — The first virus structure solved by X-ray crystallography (1978). (33 nm)

Viruses · Caulimoviridae 2

Cauliflower mosaic virus — Plant pararetrovirus; its 35S promoter drives transgenes in plants. (50 nm)
Banana streak virus — Bacilliform plant pararetrovirus. Looks the same as: Alfalfa mosaic virus. (30 × 130 nm)

Viruses · Kolmioviridae 1

Hepatitis D (delta) virus — Satellite virus needing HBV surface antigen for its envelope. (36 nm)

Viruses · Anelloviridae 1

Torque teno virus — Ubiquitous, harmless anellovirus — a marker of immune status. (30 nm)

Viruses · Filoviridae 1

Virus (ebola, marburg) — Filamentous virus folded into a shepherd's crook; haemorrhagic fever. Looks the same as: Marburg virus. (80 nm × 1 µm)

Viruses · Virgaviridae 1

Mosaic virus (tobacco, tomato) — The first virus discovered (1892): a rigid helical rod of 2 130 coat proteins. Looks the same as: Tomato mosaic virus. (18 × 300 nm)

Viruses · Alphaflexiviridae 1

Potato virus X — Flexuous filamentous plant virus, also a nanocarrier scaffold. Looks the same as: Potato virus Y. (13 × 515 nm)

Viruses · Inoviridae 1

Bacteriophage M13 — Filamentous phage behind phage display (Nobel Prize 2018). (6.5 × 900 nm)

Viruses · Straboviridae 1

Bacteriophage T4 — Iconic tailed phage: prolate head, contractile tail, baseplate and six tail fibres. Looks the same as: Bacteriophage P1, Bacteriophage Mu. (90 × 200 nm)

Viruses · Siphoviridae 1

Bacteriophage λ (lambda) — Temperate phage with a long flexible tail; model of lysis vs lysogeny. (60 nm head, 150 nm tail)

Viruses · Autographiviridae 1

Bacteriophage T7 — Short-tailed phage; source of T7 RNA polymerase. Looks the same as: Bacteriophage φ29, crAssphage. (60 nm)

Viruses · Geminiviridae 1

Maize streak virus — Twinned (geminate) capsid of two joined incomplete icosahedra. Looks the same as: Tomato yellow leaf curl virus. (22 × 38 nm)

Viruses · Fuselloviridae 1

Sulfolobus spindle-shaped virus 1 — Lemon-shaped virus of hyperthermophilic archaea. (60 × 100 nm)

Viruses · Baculoviridae 1

Baculovirus AcMNPV — Insect virus whose rods are packed in protein crystals; the baculovirus expression system. (1–3 µm polyhedra)

Parasites · Amoebae 4

Entamoeba histolytica trophozoite — Amoebic dysentery and liver abscess; trophozoites ingest red cells. (15–20 µm)
Entamoeba histolytica cyst — Infective cyst with four nuclei and chromatoid bars. (10–15 µm)
Naegleria fowleri — "Brain-eating" amoeba of warm fresh water (PAM). Looks the same as: Acanthamoeba trophozoite. (10–25 µm)
Acanthamoeba cyst — Double-walled, wrinkled cyst resistant to disinfectants. (15 µm)

Parasites · Flagellates 6

Giardia lamblia trophozoite — Pear-shaped flagellate with two nuclei ("face") and an adhesive disc; diarrhoea. (12–15 µm)
Giardia lamblia cyst — Oval cyst with four nuclei, passed in stool. (8–12 µm)
Trichomonas vaginalis — Sexually transmitted flagellate with an undulating membrane. (10–20 µm)
Trypanosoma brucei trypomastigote — African sleeping sickness; antigenic variation of its VSG coat. Looks the same as: Trypanosoma cruzi trypomastigote. (20–30 µm)
Trypanosoma cruzi amastigotes in muscle — Intracellular amastigote nests in heart muscle. Looks the same as: Leishmania amastigotes in a macrophage. (3–5 µm each)
Leishmania promastigote — Sand-fly stage with an anterior flagellum. (15–20 µm)

Parasites · Malaria parasites 4

Plasmodium falciparum ring forms — Delicate rings, often two per cell — the deadliest malaria. Looks the same as: Plasmodium knowlesi rings. (RBC ≈ 7.5 µm)
Plasmodium falciparum gametocyte — Banana-shaped sexual stage taken up by mosquitoes. (10 µm)
Plasmodium vivax trophozoite — Amoeboid trophozoite in an enlarged red cell with Schüffner dots. Looks the same as: Plasmodium malariae band form. (RBC ≈ 9 µm)
Plasmodium vivax schizont — Mature schizont with 12–24 merozoites. (RBC ≈ 9 µm)

Parasites · Apicomplexans 3

Babesia microti in red cells — Tick-borne parasite; "Maltese cross" tetrads. (RBC ≈ 7.5 µm)
Toxoplasma gondii tachyzoite — Crescent-shaped fast-dividing stage; congenital toxoplasmosis. (5 × 2 µm)
Cryptosporidium oocyst — Chlorine-resistant oocyst with four sporozoites; water-borne diarrhoea. Looks the same as: Cyclospora cayetanensis oocyst, Eimeria oocyst. (4–6 µm)

Parasites · Ciliates 1

Balantidium coli — The only ciliate that infects people. Looks the same as: Tetrahymena thermophila. (50–100 µm)

Parasites · Algae & others 1

Diatom (pennate) — Photosynthetic alga in a glass (silica) shell. (20–100 µm)

Parasites · Helminth eggs 7

Ascaris lumbricoides egg — Round, mammillated egg of the giant roundworm. (60 × 45 µm)
Trichuris trichiura egg — Barrel-shaped whipworm egg with two polar plugs. (55 × 25 µm)
Hookworm egg — Thin-shelled egg in early cleavage (Necator, Ancylostoma). Looks the same as: Fasciola hepatica egg. (65 × 40 µm)
Enterobius vermicularis egg — Pinworm egg, flattened on one side with a larva inside (Scotch-tape test). (55 × 25 µm)
Schistosoma mansoni egg — Large egg with a lateral spine; intestinal schistosomiasis. (150 × 60 µm)
Schistosoma haematobium egg — Terminal-spined egg in urine; bladder schistosomiasis. (150 × 60 µm)
Taenia egg — Round, radially striated egg with a six-hooked oncosphere. (35 µm)

Parasites · Helminth larvae 2

Wuchereria bancrofti microfilaria — Sheathed microfilaria in night blood; lymphatic filariasis. Looks the same as: Loa loa microfilaria. (250 µm long)
Strongyloides stercoralis larva — Rhabditiform larva in stool; autoinfection and hyperinfection. (250 µm long)

Bacteria · Enterobacterales 44

Escherichia coli — The workhorse of molecular biology and the commonest cause of UTI. Gram-negative, peritrichous, facultatively anaerobic gut rods; lactose fermenters. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on MacConkey agar, EMB agar, Blood agar (5% sheep), XLD agar, LB agar, CLED agar. (≈ 1.9 × 0.64 µm)
Escherichia coli O157:H7 — Shiga-toxin-producing E. coli (EHEC); sorbitol non-fermenter. Gram-negative, peritrichous, facultatively anaerobic gut rods; lactose fermenters. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on MacConkey agar, EMB agar, Blood agar (5% sheep), XLD agar, LB agar, CLED agar. (≈ 2.12 × 0.55 µm)
Escherichia coli K-12 — The laboratory strain behind most cloning hosts (DH5α, TOP10). Gram-negative, peritrichous, facultatively anaerobic gut rods; lactose fermenters. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on MacConkey agar, EMB agar, Blood agar (5% sheep), XLD agar, LB agar, CLED agar. (≈ 2.01 × 0.55 µm)
Escherichia coli BL21(DE3) — Protein-expression host carrying T7 polymerase. Gram-negative, peritrichous, facultatively anaerobic gut rods; lactose fermenters. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on MacConkey agar, EMB agar, Blood agar (5% sheep), XLD agar, LB agar, CLED agar. (≈ 1.81 × 0.62 µm)
Escherichia fergusonii — Gram-negative, peritrichous, facultatively anaerobic gut rods; lactose fermenters. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on MacConkey agar, EMB agar, Blood agar (5% sheep), XLD agar, LB agar, CLED agar. (≈ 1.84 × 0.59 µm)
Escherichia albertii — Gram-negative, peritrichous, facultatively anaerobic gut rods; lactose fermenters. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on MacConkey agar, EMB agar, Blood agar (5% sheep), XLD agar, LB agar, CLED agar. (≈ 1.88 × 0.63 µm)
Shigella flexneri — Non-motile Gram-negative rods causing bacillary dysentery; lactose non-fermenters. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on MacConkey agar, XLD agar, Hektoen enteric agar, Blood agar (5% sheep), SS agar. (≈ 2.03 × 0.61 µm)
Shigella sonnei — Non-motile Gram-negative rods causing bacillary dysentery; lactose non-fermenters. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on MacConkey agar, XLD agar, Hektoen enteric agar, Blood agar (5% sheep), SS agar. (≈ 1.69 × 0.59 µm)
Shigella dysenteriae — Makes Shiga toxin. Non-motile Gram-negative rods causing bacillary dysentery; lactose non-fermenters. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on MacConkey agar, XLD agar, Hektoen enteric agar, Blood agar (5% sheep), SS agar. (≈ 1.99 × 0.63 µm)
Shigella boydii — Non-motile Gram-negative rods causing bacillary dysentery; lactose non-fermenters. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on MacConkey agar, XLD agar, Hektoen enteric agar, Blood agar (5% sheep), SS agar. (≈ 1.59 × 0.56 µm)
Salmonella enterica serovar Typhi — Cause of typhoid fever. Motile Gram-negative rods; most make H₂S and do not ferment lactose. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on XLD agar, SS agar, Hektoen enteric agar, MacConkey agar, Blood agar (5% sheep). (≈ 2.3 × 0.63 µm)
Salmonella enterica serovar Typhimurium — Gastroenteritis and a model of host–pathogen interaction. Motile Gram-negative rods; most make H₂S and do not ferment lactose. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on XLD agar, SS agar, Hektoen enteric agar, MacConkey agar, Blood agar (5% sheep). (≈ 2.29 × 0.6 µm)
Salmonella enterica serovar Enteritidis — Egg-associated food poisoning. Motile Gram-negative rods; most make H₂S and do not ferment lactose. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on XLD agar, SS agar, Hektoen enteric agar, MacConkey agar, Blood agar (5% sheep). (≈ 2.12 × 0.6 µm)
Salmonella enterica serovar Paratyphi A — Motile Gram-negative rods; most make H₂S and do not ferment lactose. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on XLD agar, SS agar, Hektoen enteric agar, MacConkey agar, Blood agar (5% sheep). (≈ 2.46 × 0.58 µm)
Salmonella bongori — Motile Gram-negative rods; most make H₂S and do not ferment lactose. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on XLD agar, SS agar, Hektoen enteric agar, MacConkey agar, Blood agar (5% sheep). (≈ 2.38 × 0.64 µm)
Klebsiella pneumoniae — Mucoid, often carbapenem-resistant (KPC, NDM). Non-motile, heavily encapsulated Gram-negative rods with mucoid colonies. Choose the view: the cells in 3-D, a stained smear (Gram stain, India-ink capsule stain) or colonies on MacConkey agar, EMB agar, Blood agar (5% sheep), XLD agar, LB agar, CLED agar. (≈ 1.6 × 0.81 µm)
Klebsiella oxytoca — Non-motile, heavily encapsulated Gram-negative rods with mucoid colonies. Choose the view: the cells in 3-D, a stained smear (Gram stain, India-ink capsule stain) or colonies on MacConkey agar, EMB agar, Blood agar (5% sheep), XLD agar, LB agar, CLED agar. (≈ 2.02 × 0.85 µm)
Klebsiella aerogenes — Non-motile, heavily encapsulated Gram-negative rods with mucoid colonies. Choose the view: the cells in 3-D, a stained smear (Gram stain, India-ink capsule stain) or colonies on MacConkey agar, EMB agar, Blood agar (5% sheep), XLD agar, LB agar, CLED agar. (≈ 1.8 × 0.82 µm)
Klebsiella variicola — Non-motile, heavily encapsulated Gram-negative rods with mucoid colonies. Choose the view: the cells in 3-D, a stained smear (Gram stain, India-ink capsule stain) or colonies on MacConkey agar, EMB agar, Blood agar (5% sheep), XLD agar, LB agar, CLED agar. (≈ 1.88 × 0.81 µm)
Klebsiella quasipneumoniae — Non-motile, heavily encapsulated Gram-negative rods with mucoid colonies. Choose the view: the cells in 3-D, a stained smear (Gram stain, India-ink capsule stain) or colonies on MacConkey agar, EMB agar, Blood agar (5% sheep), XLD agar, LB agar, CLED agar. (≈ 1.98 × 0.8 µm)
Enterobacter cloacae — Motile Gram-negative rods; lactose fermenters and common hospital pathogens. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on MacConkey agar, EMB agar, Blood agar (5% sheep), XLD agar, LB agar, CLED agar. (≈ 2.11 × 0.54 µm)
Enterobacter hormaechei — Motile Gram-negative rods; lactose fermenters and common hospital pathogens. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on MacConkey agar, EMB agar, Blood agar (5% sheep), XLD agar, LB agar, CLED agar. (≈ 2.01 × 0.66 µm)
Enterobacter asburiae — Motile Gram-negative rods; lactose fermenters and common hospital pathogens. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on MacConkey agar, EMB agar, Blood agar (5% sheep), XLD agar, LB agar, CLED agar. (≈ 2.1 × 0.63 µm)
Enterobacter ludwigii — Motile Gram-negative rods; lactose fermenters and common hospital pathogens. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on MacConkey agar, EMB agar, Blood agar (5% sheep), XLD agar, LB agar, CLED agar. (≈ 1.85 × 0.58 µm)
Citrobacter freundii — Motile Gram-negative rods; late lactose fermenters, some make H₂S. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on XLD agar, SS agar, Hektoen enteric agar, MacConkey agar, Blood agar (5% sheep). (≈ 2.17 × 0.6 µm)
Citrobacter koseri — Motile Gram-negative rods; late lactose fermenters, some make H₂S. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on MacConkey agar, EMB agar, Blood agar (5% sheep), XLD agar, LB agar, CLED agar. (≈ 2.05 × 0.59 µm)
Citrobacter braakii — Motile Gram-negative rods; late lactose fermenters, some make H₂S. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on MacConkey agar, EMB agar, Blood agar (5% sheep), XLD agar, LB agar, CLED agar. (≈ 1.88 × 0.56 µm)
Citrobacter rodentium — Mouse model of attaching–effacing colitis. Motile Gram-negative rods; late lactose fermenters, some make H₂S. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on MacConkey agar, EMB agar, Blood agar (5% sheep), XLD agar, LB agar, CLED agar. (≈ 2.14 × 0.66 µm)
Serratia marcescens — Red prodigiosin colonies. Motile Gram-negative rods; S. marcescens makes the red pigment prodigiosin. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on MacConkey agar, EMB agar, Blood agar (5% sheep), XLD agar, LB agar, CLED agar. (≈ 1.5 × 0.62 µm)
Serratia liquefaciens — Motile Gram-negative rods; S. marcescens makes the red pigment prodigiosin. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on MacConkey agar, EMB agar, Blood agar (5% sheep), XLD agar, LB agar, CLED agar. (≈ 1.57 × 0.57 µm)
Serratia plymuthica — Motile Gram-negative rods; S. marcescens makes the red pigment prodigiosin. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on MacConkey agar, EMB agar, Blood agar (5% sheep), XLD agar, LB agar, CLED agar. (≈ 1.79 × 0.56 µm)
Proteus mirabilis — Highly motile Gram-negative rods that swarm across agar; urease and H₂S positive. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), MacConkey agar, XLD agar, CLED agar. (≈ 2.88 × 0.51 µm)
Proteus vulgaris — Highly motile Gram-negative rods that swarm across agar; urease and H₂S positive. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), MacConkey agar, XLD agar, CLED agar. (≈ 2.34 × 0.52 µm)
Proteus penneri — Highly motile Gram-negative rods that swarm across agar; urease and H₂S positive. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), MacConkey agar, XLD agar, CLED agar. (≈ 2.73 × 0.52 µm)
Morganella morganii — Urease-positive, lactose-negative Gram-negative rods. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on MacConkey agar, XLD agar, Hektoen enteric agar, Blood agar (5% sheep), SS agar. (≈ 1.83 × 0.59 µm)
Providencia stuartii — Lactose-negative Gram-negative rods of catheter-associated UTI. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on MacConkey agar, XLD agar, Hektoen enteric agar, Blood agar (5% sheep), SS agar. (≈ 1.81 × 0.55 µm)
Providencia rettgeri — Lactose-negative Gram-negative rods of catheter-associated UTI. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on MacConkey agar, XLD agar, Hektoen enteric agar, Blood agar (5% sheep), SS agar. (≈ 1.83 × 0.55 µm)
Yersinia pestis — Plague; "fried egg" colonies after 48 h. Small Gram-negative coccobacilli with bipolar staining. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on MacConkey agar, XLD agar, Hektoen enteric agar, Blood agar (5% sheep), SS agar. (≈ 1.56 × 0.73 µm)
Yersinia enterocolitica — Grows in the cold; bull's-eye colonies on CIN agar. Small Gram-negative coccobacilli with bipolar staining. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on MacConkey agar, XLD agar, Hektoen enteric agar, Blood agar (5% sheep), SS agar. (≈ 1.37 × 0.7 µm)
Yersinia pseudotuberculosis — Small Gram-negative coccobacilli with bipolar staining. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on MacConkey agar, XLD agar, Hektoen enteric agar, Blood agar (5% sheep), SS agar. (≈ 1.45 × 0.76 µm)
Cronobacter sakazakii — Gram-negative rods with yellow colonies; a risk in powdered infant formula. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on MacConkey agar, EMB agar, Blood agar (5% sheep), XLD agar, LB agar, CLED agar. (≈ 2.22 × 0.65 µm)
Pantoea agglomerans — Yellow-pigmented Gram-negative rods of plants and the environment. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on MacConkey agar, EMB agar, Blood agar (5% sheep), XLD agar, LB agar, CLED agar. (≈ 1.85 × 0.65 µm)
Edwardsiella tarda — H₂S-producing Gram-negative rods of fish and reptiles. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on XLD agar, SS agar, Hektoen enteric agar, MacConkey agar, Blood agar (5% sheep). (≈ 2.27 × 0.64 µm)
Hafnia alvei — Motile Gram-negative rods of the gut and food. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on MacConkey agar, XLD agar, Hektoen enteric agar, Blood agar (5% sheep), SS agar. (≈ 1.93 × 0.66 µm)

Bacteria · Plant pathogens 4

Erwinia amylovora — Gram-negative plant pathogens (fire blight). Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Nutrient agar, LB agar, Tryptic soy agar, Yeast–mannitol agar. (≈ 1.48 × 0.62 µm)
Pectobacterium carotovorum — Pectin-degrading soft-rot bacteria of potatoes and vegetables. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Nutrient agar, LB agar, Tryptic soy agar, Yeast–mannitol agar. (≈ 1.65 × 0.55 µm)
Xanthomonas campestris — Xanthan gum producer; black rot of cabbage. Yellow, mucoid plant pathogen; source of xanthan gum. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Nutrient agar, LB agar, Tryptic soy agar, Yeast–mannitol agar. (≈ 1.72 × 0.46 µm)
Xanthomonas oryzae — Bacterial blight of rice. Yellow, mucoid plant pathogen; source of xanthan gum. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Nutrient agar, LB agar, Tryptic soy agar, Yeast–mannitol agar. (≈ 1.82 × 0.51 µm)

Bacteria · Vibrios & relatives 12

Plesiomonas shigelloides — Oxidase-positive Gram-negative rods of fresh water and fish. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on MacConkey agar, XLD agar, Hektoen enteric agar, Blood agar (5% sheep), SS agar. (≈ 2.07 × 0.64 µm)
Aeromonas hydrophila — β-haemolytic, oxidase-positive Gram-negative rods of fresh water. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), MacConkey agar, Nutrient agar, Mueller–Hinton agar. (≈ 2.13 × 0.57 µm)
Aeromonas caviae — β-haemolytic, oxidase-positive Gram-negative rods of fresh water. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), MacConkey agar, Nutrient agar, Mueller–Hinton agar. (≈ 2.11 × 0.63 µm)
Aeromonas veronii — β-haemolytic, oxidase-positive Gram-negative rods of fresh water. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), MacConkey agar, Nutrient agar, Mueller–Hinton agar. (≈ 1.88 × 0.61 µm)
Aeromonas salmonicida — β-haemolytic, oxidase-positive Gram-negative rods of fresh water. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), MacConkey agar, Nutrient agar, Mueller–Hinton agar. (≈ 2.07 × 0.62 µm)
Vibrio cholerae — Cholera; yellow colonies on TCBS. Curved Gram-negative rods with a sheathed polar flagellum; halophilic marine bacteria. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on TCBS agar, Blood agar (5% sheep), Marine agar. (≈ 1.7 × 0.53 µm)
Vibrio parahaemolyticus — Seafood gastroenteritis; green colonies on TCBS. Curved Gram-negative rods with a sheathed polar flagellum; halophilic marine bacteria. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on TCBS agar, Blood agar (5% sheep), Marine agar. (≈ 1.75 × 0.51 µm)
Vibrio vulnificus — Wound infection from seawater. Curved Gram-negative rods with a sheathed polar flagellum; halophilic marine bacteria. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on TCBS agar, Blood agar (5% sheep), Marine agar. (≈ 1.93 × 0.51 µm)
Vibrio alginolyticus — Curved Gram-negative rods with a sheathed polar flagellum; halophilic marine bacteria. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on TCBS agar, Blood agar (5% sheep), Marine agar. (≈ 1.86 × 0.51 µm)
Vibrio harveyi — Bioluminescent marine vibrio. Curved Gram-negative rods with a sheathed polar flagellum; halophilic marine bacteria. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on TCBS agar, Blood agar (5% sheep), Marine agar. (≈ 1.85 × 0.48 µm)
Vibrio natriegens — Fastest-growing known bacterium (doubling < 10 min). Curved Gram-negative rods with a sheathed polar flagellum; halophilic marine bacteria. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on TCBS agar, Blood agar (5% sheep), Marine agar. (≈ 1.59 × 0.46 µm)
Aliivibrio fischeri — Bioluminescent squid symbiont; the classic model of quorum sensing. Bioluminescent marine vibrio, symbiont of the bobtail squid. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on TCBS agar, Blood agar (5% sheep), Marine agar. (≈ 2.01 × 0.6 µm)

Bacteria · Non-fermenting Gram-negatives 19

Pseudomonas aeruginosa — Green pyocyanin, grape-like smell, biofilms in CF lungs. Strictly aerobic, oxidase-positive Gram-negative rods with a polar flagellum. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), MacConkey agar, Cetrimide agar, Mueller–Hinton agar, King's B agar. (≈ 2.27 × 0.63 µm)
Pseudomonas fluorescens — Fluoresces under UV. Strictly aerobic, oxidase-positive Gram-negative rods with a polar flagellum. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), MacConkey agar, Cetrimide agar, Mueller–Hinton agar, King's B agar. (≈ 2.04 × 0.55 µm)
Pseudomonas putida — Soil bacterium for bioremediation and synthetic biology. Strictly aerobic, oxidase-positive Gram-negative rods with a polar flagellum. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), MacConkey agar, Cetrimide agar, Mueller–Hinton agar, King's B agar. (≈ 1.87 × 0.56 µm)
Pseudomonas syringae — Plant pathogen and ice-nucleator. Strictly aerobic, oxidase-positive Gram-negative rods with a polar flagellum. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), MacConkey agar, Cetrimide agar, Mueller–Hinton agar, King's B agar. (≈ 1.88 × 0.57 µm)
Pseudomonas stutzeri — Wrinkled, dry colonies. Strictly aerobic, oxidase-positive Gram-negative rods with a polar flagellum. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), MacConkey agar, Cetrimide agar, Mueller–Hinton agar, King's B agar. (≈ 1.89 × 0.59 µm)
Pseudomonas protegens — Biocontrol strain against plant pathogens. Strictly aerobic, oxidase-positive Gram-negative rods with a polar flagellum. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), MacConkey agar, Cetrimide agar, Mueller–Hinton agar, King's B agar. (≈ 2.25 × 0.6 µm)
Burkholderia cepacia — Aerobic Gram-negative rods; cystic fibrosis pathogens and melioidosis. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), MacConkey agar, Nutrient agar, Mueller–Hinton agar. (≈ 2.25 × 0.67 µm)
Burkholderia cenocepacia — Aerobic Gram-negative rods; cystic fibrosis pathogens and melioidosis. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), MacConkey agar, Nutrient agar, Mueller–Hinton agar. (≈ 2.2 × 0.68 µm)
Burkholderia pseudomallei — Melioidosis; wrinkled colonies. Aerobic Gram-negative rods; cystic fibrosis pathogens and melioidosis. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), MacConkey agar, Nutrient agar, Mueller–Hinton agar. (≈ 2.05 × 0.68 µm)
Burkholderia mallei — Glanders. Aerobic Gram-negative rods; cystic fibrosis pathogens and melioidosis. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), MacConkey agar, Nutrient agar, Mueller–Hinton agar. (≈ 1.77 × 0.76 µm)
Burkholderia thailandensis — Aerobic Gram-negative rods; cystic fibrosis pathogens and melioidosis. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), MacConkey agar, Nutrient agar, Mueller–Hinton agar. (≈ 1.93 × 0.65 µm)
Stenotrophomonas maltophilia — Multidrug-resistant non-fermenter with lavender-green colonies on blood agar. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), MacConkey agar, Nutrient agar, Mueller–Hinton agar. (≈ 1.43 × 0.61 µm)
Acinetobacter baumannii — Plump Gram-negative coccobacilli in pairs; hardy multidrug-resistant ICU pathogens. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), MacConkey agar, Nutrient agar, Mueller–Hinton agar. (≈ 1.31 × 0.9 µm)
Acinetobacter lwoffii — Plump Gram-negative coccobacilli in pairs; hardy multidrug-resistant ICU pathogens. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), MacConkey agar, Nutrient agar, Mueller–Hinton agar. (≈ 1.14 × 0.96 µm)
Acinetobacter calcoaceticus — Plump Gram-negative coccobacilli in pairs; hardy multidrug-resistant ICU pathogens. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), MacConkey agar, Nutrient agar, Mueller–Hinton agar. (≈ 1.48 × 0.92 µm)
Acinetobacter baylyi — Naturally competent model for genetic engineering. Plump Gram-negative coccobacilli in pairs; hardy multidrug-resistant ICU pathogens. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), MacConkey agar, Nutrient agar, Mueller–Hinton agar. (≈ 1.43 × 0.85 µm)
Achromobacter xylosoxidans — Peritrichous non-fermenter of cystic fibrosis airways. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), MacConkey agar, Nutrient agar, Mueller–Hinton agar. (≈ 1.95 × 0.61 µm)
Ralstonia solanacearum — Plant-wilt pathogen and water contaminant. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), MacConkey agar, Nutrient agar, Mueller–Hinton agar. (≈ 1.58 × 0.57 µm)
Ralstonia pickettii — Plant-wilt pathogen and water contaminant. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), MacConkey agar, Nutrient agar, Mueller–Hinton agar. (≈ 1.48 × 0.55 µm)

Bacteria · Gram-negative cocci 5

Moraxella catarrhalis — Hockey-puck colonies on blood agar. Gram-negative diplococci; colonies slide like "hockey pucks". Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Chocolate agar, Thayer–Martin agar, Blood agar (5% sheep). (≈ 0.81 µm)
Neisseria meningitidis — Meningococcal meningitis and sepsis. Kidney-bean-shaped Gram-negative diplococci; oxidase positive. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Chocolate agar, Thayer–Martin agar, Blood agar (5% sheep). (≈ 0.84 µm)
Neisseria gonorrhoeae — Gonorrhoea; grows on Thayer–Martin agar. Kidney-bean-shaped Gram-negative diplococci; oxidase positive. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Chocolate agar, Thayer–Martin agar, Blood agar (5% sheep). (≈ 0.87 µm)
Neisseria lactamica — Kidney-bean-shaped Gram-negative diplococci; oxidase positive. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Chocolate agar, Thayer–Martin agar, Blood agar (5% sheep). (≈ 0.85 µm)
Neisseria sicca — Kidney-bean-shaped Gram-negative diplococci; oxidase positive. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Chocolate agar, Thayer–Martin agar, Blood agar (5% sheep). (≈ 0.78 µm)

Bacteria · Fastidious Gram-negatives 18

Haemophilus influenzae — Meningitis and pneumonia (type b) before the Hib vaccine. Tiny Gram-negative coccobacilli needing X and V factors (grow on chocolate agar). Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Chocolate agar. (≈ 1 × 0.51 µm)
Haemophilus parainfluenzae — Tiny Gram-negative coccobacilli needing X and V factors (grow on chocolate agar). Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Chocolate agar. (≈ 1.03 × 0.53 µm)
Haemophilus ducreyi — Chancroid. Tiny Gram-negative coccobacilli needing X and V factors (grow on chocolate agar). Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Chocolate agar. (≈ 1.23 × 0.53 µm)
Pasteurella multocida — Bipolar-staining coccobacilli from animal bites. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Chocolate agar, Blood agar (5% sheep). (≈ 1.3 × 0.48 µm)
Aggregatibacter actinomycetemcomitans — HACEK coccobacillus of periodontitis and endocarditis. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Chocolate agar, Blood agar (5% sheep). (≈ 1.04 × 0.55 µm)
Eikenella corrodens — HACEK rod that pits the agar and smells of bleach. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Chocolate agar, Blood agar (5% sheep). (≈ 1.38 × 0.53 µm)
Kingella kingae — HACEK coccobacillus of childhood bone and joint infection. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Chocolate agar, Blood agar (5% sheep). (≈ 1.27 × 0.82 µm)
Bordetella pertussis — Whooping cough; "mercury drop" colonies. Tiny Gram-negative coccobacilli; B. pertussis causes whooping cough. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Regan–Lowe agar. (≈ 0.89 × 0.47 µm)
Bordetella parapertussis — Tiny Gram-negative coccobacilli; B. pertussis causes whooping cough. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Regan–Lowe agar. (≈ 1.1 × 0.53 µm)
Bordetella bronchiseptica — Kennel cough in dogs. Tiny Gram-negative coccobacilli; B. pertussis causes whooping cough. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Regan–Lowe agar. (≈ 1.03 × 0.46 µm)
Brucella melitensis — Small intracellular coccobacilli of brucellosis (a zoonosis). Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Chocolate agar, Blood agar (5% sheep). (≈ 0.86 × 0.47 µm)
Brucella abortus — Small intracellular coccobacilli of brucellosis (a zoonosis). Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Chocolate agar, Blood agar (5% sheep). (≈ 0.88 × 0.54 µm)
Brucella suis — Small intracellular coccobacilli of brucellosis (a zoonosis). Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Chocolate agar, Blood agar (5% sheep). (≈ 0.88 × 0.47 µm)
Francisella tularensis — Tiny intracellular coccobacillus of tularaemia. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Chocolate agar, Blood agar (5% sheep). (≈ 0.75 × 0.42 µm)
Francisella novicida — Tiny intracellular coccobacillus of tularaemia. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Chocolate agar, Blood agar (5% sheep). (≈ 0.74 × 0.39 µm)
Legionella pneumophila — Legionnaires' disease from cooling towers and showers. Thin Gram-negative rods from water systems; grow only on BCYE agar. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on BCYE agar. (≈ 2.43 × 0.46 µm)
Legionella longbeachae — Thin Gram-negative rods from water systems; grow only on BCYE agar. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on BCYE agar. (≈ 2.73 × 0.48 µm)
Legionella micdadei — Thin Gram-negative rods from water systems; grow only on BCYE agar. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on BCYE agar. (≈ 2.48 × 0.55 µm)

Bacteria · Intracellular bacteria 8

Coxiella burnetii — Obligate intracellular agent of Q fever. Choose the view: the cells in 3-D, a stained smear (Giemsa stain) or colonies on agar. (≈ 0.52 × 0.41 µm)
Bartonella henselae — Small curved rods of cat-scratch disease and trench fever. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Chocolate agar, Blood agar (5% sheep). (≈ 1.55 × 0.43 µm)
Bartonella quintana — Small curved rods of cat-scratch disease and trench fever. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Chocolate agar, Blood agar (5% sheep). (≈ 1.49 × 0.41 µm)
Rickettsia rickettsii — Rocky Mountain spotted fever. Obligate intracellular bacteria spread by ticks and lice. Choose the view: the cells in 3-D, a stained smear (Giemsa stain) or colonies on agar. (≈ 1.1 × 0.43 µm)
Rickettsia prowazekii — Epidemic typhus. Obligate intracellular bacteria spread by ticks and lice. Choose the view: the cells in 3-D, a stained smear (Giemsa stain) or colonies on agar. (≈ 0.88 × 0.38 µm)
Chlamydia trachomatis — The commonest bacterial STI and cause of trachoma. Obligate intracellular bacteria alternating between elementary and reticulate bodies. Choose the view: the cells in 3-D, a stained smear (Giemsa stain) or colonies on agar. (≈ 0.37 µm)
Chlamydia pneumoniae — Obligate intracellular bacteria alternating between elementary and reticulate bodies. Choose the view: the cells in 3-D, a stained smear (Giemsa stain) or colonies on agar. (≈ 0.4 µm)
Wolbachia pipientis — Insect endosymbiont used to block dengue in mosquitoes. Choose the view: the cells in 3-D, a stained smear (Giemsa stain) or colonies on agar. (≈ 0.74 × 0.49 µm)

Bacteria · Anaerobes 14

Bacteroides fragilis — Anaerobic abscesses; black colonies on BBE agar. Pleomorphic anaerobic Gram-negative rods — the most abundant gut genus. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Anaerobic blood agar, BBE agar. (≈ 2.05 × 0.58 µm)
Bacteroides thetaiotaomicron — Gut glycan-degrading model. Pleomorphic anaerobic Gram-negative rods — the most abundant gut genus. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Anaerobic blood agar, BBE agar. (≈ 1.78 × 0.54 µm)
Phocaeicola vulgatus — Anaerobic gut Gram-negative rod (formerly Bacteroides). Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Anaerobic blood agar, BBE agar. (≈ 2.01 × 0.55 µm)
Prevotella melaninogenica — Black-pigmented anaerobic coccobacilli of the mouth. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Anaerobic blood agar, BBE agar. (≈ 1.04 × 0.65 µm)
Prevotella intermedia — Black-pigmented anaerobic coccobacilli of the mouth. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Anaerobic blood agar, BBE agar. (≈ 1.12 × 0.58 µm)
Porphyromonas gingivalis — Keystone pathogen of periodontitis. Black-pigmented anaerobe of periodontitis. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Anaerobic blood agar, BBE agar. (≈ 1.12 × 0.65 µm)
Fusobacterium nucleatum — Oral anaerobe linked to colorectal cancer. Long, spindle-shaped anaerobic Gram-negative rods with tapered ends. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Anaerobic blood agar, BBE agar. (≈ 5.43 × 0.49 µm)
Fusobacterium necrophorum — Lemierre's syndrome. Long, spindle-shaped anaerobic Gram-negative rods with tapered ends. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Anaerobic blood agar, BBE agar. (≈ 5.64 × 0.49 µm)
Akkermansia muciniphila — Mucin-degrading gut anaerobe linked to metabolic health. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Anaerobic blood agar, BBE agar. (≈ 1.07 × 0.74 µm)
Veillonella parvula — Tiny anaerobic Gram-negative cocci of the mouth and gut. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Anaerobic blood agar, BBE agar. (≈ 0.54 µm)
Faecalibacterium prausnitzii — Butyrate-producing gut anaerobe (stains Gram-variable). Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Anaerobic blood agar, MRS agar. (≈ 2.47 × 0.66 µm)
Roseburia intestinalis — Curved, butyrate-producing gut anaerobe. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Anaerobic blood agar, MRS agar. (≈ 2.67 × 0.53 µm)
Ruminococcus bromii — Starch-degrading gut cocci. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Anaerobic blood agar, MRS agar. (≈ 1 µm)
Peptostreptococcus anaerobius — Anaerobic Gram-positive cocci in chains. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Anaerobic blood agar, MRS agar. (≈ 0.87 µm)

Bacteria · Actinobacteria 14

Actinomyces israelii — Actinomycosis with sulphur granules; "molar tooth" colonies. Branching anaerobic filaments forming "sulphur granules". Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Anaerobic blood agar, MRS agar. (≈ 5.74 × 0.56 µm)
Actinomyces naeslundii — Branching anaerobic filaments forming "sulphur granules". Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Anaerobic blood agar, MRS agar. (≈ 5.47 × 0.57 µm)
Rhodococcus equi — Salmon-pink, partially acid-fast actinomycete. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on ISP2 (yeast–malt) agar, Blood agar (5% sheep), Nutrient agar. (≈ 1.6 × 0.81 µm)
Rhodococcus erythropolis — Salmon-pink, partially acid-fast actinomycete. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on ISP2 (yeast–malt) agar, Blood agar (5% sheep), Nutrient agar. (≈ 1.48 × 0.79 µm)
Nocardia asteroides — Branching, weakly acid-fast aerobic filaments with chalky colonies. Choose the view: the cells in 3-D, a stained smear (Ziehl–Neelsen (acid-fast) stain) or colonies on ISP2 (yeast–malt) agar, Blood agar (5% sheep), Nutrient agar. (≈ 6.89 × 0.61 µm)
Nocardia brasiliensis — Mycetoma. Branching, weakly acid-fast aerobic filaments with chalky colonies. Choose the view: the cells in 3-D, a stained smear (Ziehl–Neelsen (acid-fast) stain) or colonies on ISP2 (yeast–malt) agar, Blood agar (5% sheep), Nutrient agar. (≈ 7.59 × 0.57 µm)
Nocardia farcinica — Branching, weakly acid-fast aerobic filaments with chalky colonies. Choose the view: the cells in 3-D, a stained smear (Ziehl–Neelsen (acid-fast) stain) or colonies on ISP2 (yeast–malt) agar, Blood agar (5% sheep), Nutrient agar. (≈ 7.73 × 0.61 µm)
Streptomyces coelicolor — Model antibiotic producer; blue actinorhodin pigment. Soil filaments with aerial spore chains; source of most antibiotics; earthy smell (geosmin). Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on ISP2 (yeast–malt) agar, Blood agar (5% sheep), Nutrient agar. (≈ 10.39 × 0.79 µm)
Streptomyces griseus — Source of streptomycin. Soil filaments with aerial spore chains; source of most antibiotics; earthy smell (geosmin). Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on ISP2 (yeast–malt) agar, Blood agar (5% sheep), Nutrient agar. (≈ 10.67 × 0.8 µm)
Streptomyces venezuelae — Source of chloramphenicol. Soil filaments with aerial spore chains; source of most antibiotics; earthy smell (geosmin). Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on ISP2 (yeast–malt) agar, Blood agar (5% sheep), Nutrient agar. (≈ 10.64 × 0.75 µm)
Streptomyces avermitilis — Source of ivermectin (Nobel Prize 2015). Soil filaments with aerial spore chains; source of most antibiotics; earthy smell (geosmin). Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on ISP2 (yeast–malt) agar, Blood agar (5% sheep), Nutrient agar. (≈ 10.53 × 0.87 µm)
Streptomyces scabiei — Potato scab. Soil filaments with aerial spore chains; source of most antibiotics; earthy smell (geosmin). Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on ISP2 (yeast–malt) agar, Blood agar (5% sheep), Nutrient agar. (≈ 10.96 × 0.76 µm)
Streptomyces clavuligerus — Source of clavulanic acid. Soil filaments with aerial spore chains; source of most antibiotics; earthy smell (geosmin). Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on ISP2 (yeast–malt) agar, Blood agar (5% sheep), Nutrient agar. (≈ 9.79 × 0.86 µm)
Streptomyces lividans — Soil filaments with aerial spore chains; source of most antibiotics; earthy smell (geosmin). Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on ISP2 (yeast–malt) agar, Blood agar (5% sheep), Nutrient agar. (≈ 9.62 × 0.76 µm)

Bacteria · Environmental bacteria 9

Caulobacter crescentus — Crescent-shaped stalked bacterium; a model of the bacterial cell cycle. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Nutrient agar, LB agar, Tryptic soy agar, Yeast–mannitol agar. (≈ 2.04 × 0.46 µm)
Azotobacter vinelandii — Large free-living nitrogen-fixer that forms cysts. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Nutrient agar, LB agar, Tryptic soy agar, Yeast–mannitol agar. (≈ 2.17 × 1.73 µm)
Chromobacterium violaceum — Makes the purple pigment violacein; a model for quorum sensing. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Nutrient agar, LB agar, Tryptic soy agar, Yeast–mannitol agar. (≈ 2.57 × 0.83 µm)
Myxococcus xanthus — Swarms and builds fruiting bodies when starved. Gliding predatory bacterium that builds multicellular fruiting bodies. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Nutrient agar, LB agar, Tryptic soy agar, Yeast–mannitol agar. (≈ 4.76 × 0.55 µm)
Bdellovibrio bacteriovorus — Tiny predatory bacterium that invades other Gram-negatives. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on agar. (≈ 1.11 × 0.28 µm)
Geobacter sulfurreducens — Metal-reducing bacterium with conductive pili ("nanowires"). Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Nutrient agar, LB agar, Tryptic soy agar, Yeast–mannitol agar. (≈ 2.01 × 0.53 µm)
Shewanella oneidensis — Metal-reducing marine bacterium used in microbial fuel cells. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Nutrient agar, LB agar, Tryptic soy agar, Yeast–mannitol agar. (≈ 2.11 × 0.55 µm)
Nitrosomonas europaea — Ammonia-oxidising bacterium of the nitrogen cycle. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Nutrient agar, LB agar, Tryptic soy agar, Yeast–mannitol agar. (≈ 1.64 × 0.83 µm)
Nitrobacter winogradskyi — Nitrite-oxidising bacterium of the nitrogen cycle. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Nutrient agar, LB agar, Tryptic soy agar, Yeast–mannitol agar. (≈ 1.4 × 0.76 µm)

Bacteria · Plant-associated bacteria 5

Agrobacterium tumefaciens — Plant tumour bacterium that transfers T-DNA — the tool for plant genetic engineering. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Nutrient agar, LB agar, Tryptic soy agar, Yeast–mannitol agar. (≈ 1.99 × 0.73 µm)
Rhizobium leguminosarum — Nitrogen-fixing symbiont of legume root nodules; mucoid colonies. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Nutrient agar, LB agar, Tryptic soy agar, Yeast–mannitol agar. (≈ 1.91 × 0.66 µm)
Rhizobium etli — Nitrogen-fixing symbiont of legume root nodules; mucoid colonies. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Nutrient agar, LB agar, Tryptic soy agar, Yeast–mannitol agar. (≈ 1.72 × 0.73 µm)
Sinorhizobium meliloti — Nitrogen-fixing alfalfa symbiont. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Nutrient agar, LB agar, Tryptic soy agar, Yeast–mannitol agar. (≈ 1.57 × 0.72 µm)
Bradyrhizobium japonicum — Slow-growing soybean nodule symbiont. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Nutrient agar, LB agar, Tryptic soy agar, Yeast–mannitol agar. (≈ 1.44 × 0.62 µm)

Bacteria · Industrial bacteria 3

Zymomonas mobilis — Ethanol-producing bacterium used for biofuels. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Nutrient agar, LB agar, Tryptic soy agar, Yeast–mannitol agar. (≈ 2.85 × 1.31 µm)
Gluconobacter oxydans — Acetic acid bacterium used for vitamin C synthesis. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Nutrient agar, LB agar, Tryptic soy agar, Yeast–mannitol agar. (≈ 1.8 × 0.68 µm)
Acetobacter aceti — Vinegar bacterium that oxidises ethanol to acetic acid. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Nutrient agar, LB agar, Tryptic soy agar, Yeast–mannitol agar. (≈ 2.11 × 0.74 µm)

Bacteria · Extremophiles 3

Thermus aquaticus — Thermophile from hot springs; source of Taq polymerase. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Tryptic soy agar, Nutrient agar. (≈ 3.78 × 0.57 µm)
Thermus thermophilus — Thermophile from hot springs; source of Taq polymerase. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Tryptic soy agar, Nutrient agar. (≈ 4.07 × 0.62 µm)
Deinococcus radiodurans — Survives 5 000 Gy of radiation. Radiation-resistant red cocci in tetrads. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Tryptic soy agar, Nutrient agar. (≈ 1.56 µm)

Bacteria · Cyanobacteria 7

Synechococcus elongatus — Tiny marine cyanobacterium, a major ocean photosynthesiser. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on BG-11 agar. (≈ 1.63 × 0.93 µm)
Prochlorococcus marinus — The smallest and most abundant photosynthetic organism on Earth. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on BG-11 agar. (≈ 0.61 µm)
Synechocystis sp. PCC 6803 — Model unicellular cyanobacterium for photosynthesis research. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on BG-11 agar. (≈ 2.03 µm)
Nostoc punctiforme — Bead-like filaments with nitrogen-fixing heterocysts. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on BG-11 agar. (≈ 3.07 × 2.82 µm)
Anabaena sp. PCC 7120 — Filamentous cyanobacterium with heterocysts; forms blooms. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on BG-11 agar. (≈ 2.61 × 3.24 µm)
Arthrospira platensis — Spiral filaments sold as "spirulina". Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on BG-11 agar. (≈ 45 × 6.13 µm)
Trichodesmium erythraeum — Ocean nitrogen-fixer forming colonies visible to the eye. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on BG-11 agar. (≈ 7.75 × 6.16 µm)

Bacteria · Gram-positive cocci 27

Staphylococcus aureus — Skin infections, sepsis, MRSA; golden β-haemolytic colonies. Gram-positive cocci in grape-like clusters; catalase positive. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), Mannitol salt agar, Nutrient agar, Baird–Parker agar. (≈ 1.04 µm)
Staphylococcus epidermidis — Implant and catheter biofilms. Gram-positive cocci in grape-like clusters; catalase positive. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), Mannitol salt agar, Nutrient agar, Baird–Parker agar. (≈ 1.1 µm)
Staphylococcus saprophyticus — UTI in young women; novobiocin resistant. Gram-positive cocci in grape-like clusters; catalase positive. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), Mannitol salt agar, Nutrient agar, Baird–Parker agar. (≈ 1.09 µm)
Staphylococcus haemolyticus — Gram-positive cocci in grape-like clusters; catalase positive. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), Mannitol salt agar, Nutrient agar, Baird–Parker agar. (≈ 1.07 µm)
Staphylococcus lugdunensis — Gram-positive cocci in grape-like clusters; catalase positive. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), Mannitol salt agar, Nutrient agar, Baird–Parker agar. (≈ 0.96 µm)
Staphylococcus hominis — Gram-positive cocci in grape-like clusters; catalase positive. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), Mannitol salt agar, Nutrient agar, Baird–Parker agar. (≈ 1.08 µm)
Staphylococcus capitis — Gram-positive cocci in grape-like clusters; catalase positive. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), Mannitol salt agar, Nutrient agar, Baird–Parker agar. (≈ 0.94 µm)
Staphylococcus pseudintermedius — Dog skin pathogen. Gram-positive cocci in grape-like clusters; catalase positive. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), Mannitol salt agar, Nutrient agar, Baird–Parker agar. (≈ 1.04 µm)
Streptococcus pyogenes — Group A strep: pharyngitis, impetigo, necrotising fasciitis. Gram-positive cocci in chains or pairs; catalase negative. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), Chocolate agar. (≈ 0.87 µm)
Streptococcus agalactiae — Group B strep: neonatal sepsis. Gram-positive cocci in chains or pairs; catalase negative. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), Chocolate agar. (≈ 0.92 µm)
Streptococcus pneumoniae — Pneumococcus; lancet diplococci with α-haemolytic "draughtsman" colonies. Gram-positive cocci in chains or pairs; catalase negative. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), Chocolate agar. (≈ 0.98 µm)
Streptococcus mutans — Dental caries. Gram-positive cocci in chains or pairs; catalase negative. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), Chocolate agar. (≈ 0.88 µm)
Streptococcus mitis — Gram-positive cocci in chains or pairs; catalase negative. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), Chocolate agar. (≈ 0.89 µm)
Streptococcus sanguinis — Gram-positive cocci in chains or pairs; catalase negative. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), Chocolate agar. (≈ 0.84 µm)
Streptococcus salivarius — Gram-positive cocci in chains or pairs; catalase negative. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), Chocolate agar. (≈ 0.85 µm)
Streptococcus gallolyticus — Associated with colon cancer. Gram-positive cocci in chains or pairs; catalase negative. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), Chocolate agar. (≈ 0.87 µm)
Streptococcus dysgalactiae — Gram-positive cocci in chains or pairs; catalase negative. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), Chocolate agar. (≈ 0.85 µm)
Streptococcus anginosus — Gram-positive cocci in chains or pairs; catalase negative. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), Chocolate agar. (≈ 0.88 µm)
Streptococcus suis — Gram-positive cocci in chains or pairs; catalase negative. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), Chocolate agar. (≈ 0.92 µm)
Streptococcus thermophilus — Yogurt starter. Gram-positive cocci in chains or pairs; catalase negative. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), Chocolate agar. (≈ 0.86 µm)
Streptococcus equi — Gram-positive cocci in chains or pairs; catalase negative. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), Chocolate agar. (≈ 0.92 µm)
Enterococcus faecalis — Hardy Gram-positive cocci in pairs and short chains; grow in bile and 6.5% salt. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), Bile–esculin agar, MacConkey agar. (≈ 0.87 µm)
Enterococcus faecium — Vancomycin-resistant (VRE) hospital pathogen. Hardy Gram-positive cocci in pairs and short chains; grow in bile and 6.5% salt. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), Bile–esculin agar, MacConkey agar. (≈ 0.83 µm)
Enterococcus gallinarum — Hardy Gram-positive cocci in pairs and short chains; grow in bile and 6.5% salt. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), Bile–esculin agar, MacConkey agar. (≈ 0.86 µm)
Enterococcus casseliflavus — Hardy Gram-positive cocci in pairs and short chains; grow in bile and 6.5% salt. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), Bile–esculin agar, MacConkey agar. (≈ 0.86 µm)
Micrococcus luteus — Yellow colonies; classic lysozyme substrate. Gram-positive cocci in tetrads with yellow colonies; common on skin. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), Mannitol salt agar, Nutrient agar, Baird–Parker agar. (≈ 1.29 µm)
Kocuria rosea — Pink-pigmented Gram-positive cocci of skin and soil. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Blood agar (5% sheep), Mannitol salt agar, Nutrient agar, Baird–Parker agar. (≈ 1.17 µm)

Bacteria · Lactic acid bacteria 16

Lactococcus lactis — Dairy starter coccus used for cheese and as a protein-expression host. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on MRS agar, Blood agar (5% sheep). (≈ 0.91 µm)
Leuconostoc mesenteroides — Lens-shaped cocci of fermented vegetables; make dextran slime. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on MRS agar, Blood agar (5% sheep). (≈ 0.74 µm)
Pediococcus acidilactici — Lactic acid cocci in tetrads used in sausage and silage fermentation. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on MRS agar, Blood agar (5% sheep). (≈ 1.08 µm)
Lactobacillus acidophilus — Long Gram-positive rods of yogurt, the vagina and the gut; probiotics. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on MRS agar, Blood agar (5% sheep). (≈ 4.05 × 0.77 µm)
Lactobacillus delbrueckii subsp. bulgaricus — Yogurt starter. Long Gram-positive rods of yogurt, the vagina and the gut; probiotics. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on MRS agar, Blood agar (5% sheep). (≈ 4.28 × 0.77 µm)
Lactobacillus crispatus — Dominant healthy vaginal lactobacillus. Long Gram-positive rods of yogurt, the vagina and the gut; probiotics. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on MRS agar, Blood agar (5% sheep). (≈ 4.46 × 0.81 µm)
Lactobacillus gasseri — Long Gram-positive rods of yogurt, the vagina and the gut; probiotics. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on MRS agar, Blood agar (5% sheep). (≈ 4.22 × 0.81 µm)
Lactobacillus helveticus — Long Gram-positive rods of yogurt, the vagina and the gut; probiotics. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on MRS agar, Blood agar (5% sheep). (≈ 3.57 × 0.76 µm)
Lactiplantibacillus plantarum — Versatile lactic acid rod of fermented plant foods. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on MRS agar, Blood agar (5% sheep). (≈ 2.75 × 0.81 µm)
Lacticaseibacillus rhamnosus — LGG probiotic. Probiotic lactic acid rod (e.g. LGG). Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on MRS agar, Blood agar (5% sheep). (≈ 2.59 × 0.74 µm)
Lacticaseibacillus casei — Probiotic lactic acid rod (e.g. LGG). Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on MRS agar, Blood agar (5% sheep). (≈ 2.33 × 0.78 µm)
Limosilactobacillus reuteri — Gut lactic acid rod that makes reuterin. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on MRS agar, Blood agar (5% sheep). (≈ 2.51 × 0.8 µm)
Bifidobacterium longum — Branched (Y-shaped) anaerobic rods of the infant gut; probiotics. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Anaerobic blood agar, MRS agar. (≈ 2.99 × 0.83 µm)
Bifidobacterium bifidum — Branched (Y-shaped) anaerobic rods of the infant gut; probiotics. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Anaerobic blood agar, MRS agar. (≈ 2.62 × 0.73 µm)
Bifidobacterium breve — Branched (Y-shaped) anaerobic rods of the infant gut; probiotics. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Anaerobic blood agar, MRS agar. (≈ 2.65 × 0.86 µm)
Bifidobacterium animalis subsp. lactis — Branched (Y-shaped) anaerobic rods of the infant gut; probiotics. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Anaerobic blood agar, MRS agar. (≈ 3.23 × 0.87 µm)

Bacteria · Spore-forming rods 21

Bacillus subtilis — Gram-positive model organism and spore former. Large aerobic Gram-positive rods that form heat-resistant endospores. Choose the view: the cells in 3-D, a stained smear (Gram stain, spore stain) or colonies on Blood agar (5% sheep), Nutrient agar, LB agar. (≈ 2.88 × 1.06 µm)
Bacillus cereus — Fried-rice food poisoning; β-haemolytic. Large aerobic Gram-positive rods that form heat-resistant endospores. Choose the view: the cells in 3-D, a stained smear (Gram stain, spore stain) or colonies on Blood agar (5% sheep), Nutrient agar, LB agar. (≈ 3.3 × 1.08 µm)
Bacillus anthracis — Anthrax; non-haemolytic "medusa head" colonies. Large aerobic Gram-positive rods that form heat-resistant endospores. Choose the view: the cells in 3-D, a stained smear (Gram stain, spore stain) or colonies on Blood agar (5% sheep), Nutrient agar, LB agar. (≈ 2.78 × 1.07 µm)
Bacillus thuringiensis — Makes Bt insecticidal crystal toxins. Large aerobic Gram-positive rods that form heat-resistant endospores. Choose the view: the cells in 3-D, a stained smear (Gram stain, spore stain) or colonies on Blood agar (5% sheep), Nutrient agar, LB agar. (≈ 2.7 × 1.09 µm)
Bacillus licheniformis — Large aerobic Gram-positive rods that form heat-resistant endospores. Choose the view: the cells in 3-D, a stained smear (Gram stain, spore stain) or colonies on Blood agar (5% sheep), Nutrient agar, LB agar. (≈ 2.65 × 1.07 µm)
Bacillus megaterium — Very large cells. Large aerobic Gram-positive rods that form heat-resistant endospores. Choose the view: the cells in 3-D, a stained smear (Gram stain, spore stain) or colonies on Blood agar (5% sheep), Nutrient agar, LB agar. (≈ 3.31 × 0.96 µm)
Bacillus amyloliquefaciens — Large aerobic Gram-positive rods that form heat-resistant endospores. Choose the view: the cells in 3-D, a stained smear (Gram stain, spore stain) or colonies on Blood agar (5% sheep), Nutrient agar, LB agar. (≈ 3.34 × 1.08 µm)
Bacillus pumilus — Large aerobic Gram-positive rods that form heat-resistant endospores. Choose the view: the cells in 3-D, a stained smear (Gram stain, spore stain) or colonies on Blood agar (5% sheep), Nutrient agar, LB agar. (≈ 2.59 × 1.08 µm)
Bacillus velezensis — Large aerobic Gram-positive rods that form heat-resistant endospores. Choose the view: the cells in 3-D, a stained smear (Gram stain, spore stain) or colonies on Blood agar (5% sheep), Nutrient agar, LB agar. (≈ 3.28 × 1.02 µm)
Geobacillus stearothermophilus — Thermophilic spore former used to test autoclaves. Choose the view: the cells in 3-D, a stained smear (Gram stain, spore stain) or colonies on Blood agar (5% sheep), Nutrient agar, LB agar. (≈ 3.25 × 0.77 µm)
Paenibacillus larvae — Spore-forming rods; P. larvae causes American foulbrood of bees. Choose the view: the cells in 3-D, a stained smear (Gram stain, spore stain) or colonies on Blood agar (5% sheep), Nutrient agar, LB agar. (≈ 2.92 × 0.65 µm)
Paenibacillus polymyxa — Source of polymyxin antibiotics. Spore-forming rods; P. larvae causes American foulbrood of bees. Choose the view: the cells in 3-D, a stained smear (Gram stain, spore stain) or colonies on Blood agar (5% sheep), Nutrient agar, LB agar. (≈ 3.07 × 0.64 µm)
Clostridioides difficile — Antibiotic-associated colitis; ground-glass colonies, horse-stable smell. Anaerobic spore former of antibiotic-associated colitis. Choose the view: the cells in 3-D, a stained smear (Gram stain, spore stain) or colonies on Anaerobic blood agar, Egg-yolk agar, CCFA agar. (≈ 3.47 × 0.75 µm)
Clostridium perfringens — Gas gangrene and food poisoning; double zone of haemolysis. Anaerobic Gram-positive rods with swollen endospores; many make toxins. Choose the view: the cells in 3-D, a stained smear (Gram stain, spore stain) or colonies on Anaerobic blood agar, Egg-yolk agar, CCFA agar. (≈ 4.37 × 0.87 µm)
Clostridium botulinum — Botulinum toxin. Anaerobic Gram-positive rods with swollen endospores; many make toxins. Choose the view: the cells in 3-D, a stained smear (Gram stain, spore stain) or colonies on Anaerobic blood agar, Egg-yolk agar, CCFA agar. (≈ 3.72 × 0.95 µm)
Clostridium tetani — Tetanus; drumstick spores and a swarming film. Anaerobic Gram-positive rods with swollen endospores; many make toxins. Choose the view: the cells in 3-D, a stained smear (Gram stain, spore stain) or colonies on Anaerobic blood agar, Egg-yolk agar, CCFA agar. (≈ 3.75 × 0.9 µm)
Clostridium septicum — Anaerobic Gram-positive rods with swollen endospores; many make toxins. Choose the view: the cells in 3-D, a stained smear (Gram stain, spore stain) or colonies on Anaerobic blood agar, Egg-yolk agar, CCFA agar. (≈ 4.23 × 0.83 µm)
Clostridium sporogenes — Anaerobic Gram-positive rods with swollen endospores; many make toxins. Choose the view: the cells in 3-D, a stained smear (Gram stain, spore stain) or colonies on Anaerobic blood agar, Egg-yolk agar, CCFA agar. (≈ 3.89 × 0.93 µm)
Clostridium acetobutylicum — ABE fermentation for butanol. Anaerobic Gram-positive rods with swollen endospores; many make toxins. Choose the view: the cells in 3-D, a stained smear (Gram stain, spore stain) or colonies on Anaerobic blood agar, Egg-yolk agar, CCFA agar. (≈ 3.97 × 0.84 µm)
Clostridium novyi — Anaerobic Gram-positive rods with swollen endospores; many make toxins. Choose the view: the cells in 3-D, a stained smear (Gram stain, spore stain) or colonies on Anaerobic blood agar, Egg-yolk agar, CCFA agar. (≈ 3.61 × 0.95 µm)
Clostridium butyricum — Anaerobic Gram-positive rods with swollen endospores; many make toxins. Choose the view: the cells in 3-D, a stained smear (Gram stain, spore stain) or colonies on Anaerobic blood agar, Egg-yolk agar, CCFA agar. (≈ 4.48 × 0.85 µm)

Bacteria · Mycobacteria 12

Mycobacterium tuberculosis — Tuberculosis; rough, buff "breadcrumb" colonies after 3–6 weeks on LJ. Thin, acid-fast rods with a waxy mycolic-acid wall; slow growing. Choose the view: the cells in 3-D, a stained smear (Ziehl–Neelsen (acid-fast) stain) or colonies on Löwenstein–Jensen medium, Middlebrook 7H10 agar. (≈ 3.13 × 0.42 µm)
Mycobacterium bovis BCG — The tuberculosis vaccine strain. Thin, acid-fast rods with a waxy mycolic-acid wall; slow growing. Choose the view: the cells in 3-D, a stained smear (Ziehl–Neelsen (acid-fast) stain) or colonies on Löwenstein–Jensen medium, Middlebrook 7H10 agar. (≈ 3.09 × 0.38 µm)
Mycobacterium leprae — Leprosy (cannot be grown in culture). Thin, acid-fast rods with a waxy mycolic-acid wall; slow growing. Choose the view: the cells in 3-D, a stained smear (Ziehl–Neelsen (acid-fast) stain) or colonies on agar. (≈ 3.33 × 0.42 µm)
Mycobacterium avium — MAC infection in AIDS; smooth colonies. Thin, acid-fast rods with a waxy mycolic-acid wall; slow growing. Choose the view: the cells in 3-D, a stained smear (Ziehl–Neelsen (acid-fast) stain) or colonies on Löwenstein–Jensen medium, Middlebrook 7H10 agar. (≈ 2.87 × 0.36 µm)
Mycobacterium intracellulare — Thin, acid-fast rods with a waxy mycolic-acid wall; slow growing. Choose the view: the cells in 3-D, a stained smear (Ziehl–Neelsen (acid-fast) stain) or colonies on Löwenstein–Jensen medium, Middlebrook 7H10 agar. (≈ 3.06 × 0.42 µm)
Mycobacterium kansasii — Photochromogen: yellow in light. Thin, acid-fast rods with a waxy mycolic-acid wall; slow growing. Choose the view: the cells in 3-D, a stained smear (Ziehl–Neelsen (acid-fast) stain) or colonies on Löwenstein–Jensen medium, Middlebrook 7H10 agar. (≈ 2.98 × 0.38 µm)
Mycobacterium marinum — Fish-tank granuloma; photochromogen. Thin, acid-fast rods with a waxy mycolic-acid wall; slow growing. Choose the view: the cells in 3-D, a stained smear (Ziehl–Neelsen (acid-fast) stain) or colonies on Löwenstein–Jensen medium, Middlebrook 7H10 agar. (≈ 2.74 × 0.42 µm)
Mycobacterium ulcerans — Buruli ulcer. Thin, acid-fast rods with a waxy mycolic-acid wall; slow growing. Choose the view: the cells in 3-D, a stained smear (Ziehl–Neelsen (acid-fast) stain) or colonies on Löwenstein–Jensen medium, Middlebrook 7H10 agar. (≈ 2.66 × 0.38 µm)
Mycobacterium smegmatis — Fast-growing model mycobacterium. Thin, acid-fast rods with a waxy mycolic-acid wall; slow growing. Choose the view: the cells in 3-D, a stained smear (Ziehl–Neelsen (acid-fast) stain) or colonies on Löwenstein–Jensen medium, Middlebrook 7H10 agar, Blood agar (5% sheep). (≈ 3.31 × 0.39 µm)
Mycobacterium abscessus — Rapid grower infecting CF lungs. Thin, acid-fast rods with a waxy mycolic-acid wall; slow growing. Choose the view: the cells in 3-D, a stained smear (Ziehl–Neelsen (acid-fast) stain) or colonies on Löwenstein–Jensen medium, Middlebrook 7H10 agar, Blood agar (5% sheep). (≈ 3.07 × 0.4 µm)
Mycobacterium fortuitum — Thin, acid-fast rods with a waxy mycolic-acid wall; slow growing. Choose the view: the cells in 3-D, a stained smear (Ziehl–Neelsen (acid-fast) stain) or colonies on Löwenstein–Jensen medium, Middlebrook 7H10 agar, Blood agar (5% sheep). (≈ 3.41 × 0.38 µm)
Mycobacterium chelonae — Thin, acid-fast rods with a waxy mycolic-acid wall; slow growing. Choose the view: the cells in 3-D, a stained smear (Ziehl–Neelsen (acid-fast) stain) or colonies on Löwenstein–Jensen medium, Middlebrook 7H10 agar, Blood agar (5% sheep). (≈ 2.62 × 0.41 µm)

Bacteria · Wall-less bacteria 5

Mycoplasmoides pneumoniae — "Walking pneumonia". Flask-shaped wall-less bacteria with an attachment tip. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on PPLO (Mycoplasma) agar. (≈ 0.56 × 0.21 µm)
Mycoplasmoides genitalium — Flask-shaped wall-less bacteria with an attachment tip. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on PPLO (Mycoplasma) agar. (≈ 0.45 × 0.19 µm)
Mycoplasma hominis — The smallest free-living cells: no cell wall, fried-egg colonies. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on PPLO (Mycoplasma) agar. (≈ 0.41 × 0.3 µm)
Mycoplasma mycoides — Host of the first synthetic genome (JCVI-syn1.0). The smallest free-living cells: no cell wall, fried-egg colonies. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on PPLO (Mycoplasma) agar. (≈ 0.43 × 0.29 µm)
Ureaplasma urealyticum — Urease-positive wall-less bacterium of the urogenital tract. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on PPLO (Mycoplasma) agar. (≈ 0.39 × 0.32 µm)

Archaea · Archaea 10

Halobacterium salinarum — Salt-loving archaeon coloured red by bacterioruberin, with light-driven bacteriorhodopsin. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Halophile agar (25% NaCl). (≈ 3.88 × 0.55 µm)
Haloferax volcanii — Flat, pleomorphic model haloarchaeon. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on Halophile agar (25% NaCl). (≈ 2.14 × 2.04 µm)
Methanobrevibacter smithii — The main methane-producing archaeon of the human gut. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on agar. (≈ 1.21 × 0.65 µm)
Methanococcus maripaludis — Marine methanogen used as an archaeal model. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on agar. (≈ 1.57 µm)
Sulfolobus acidocaldarius — Lobed thermoacidophile from sulfur springs (80 °C, pH 3). Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on agar. (≈ 0.99 × 1.06 µm)
Saccharolobus solfataricus — Thermoacidophilic archaeon with a lobed cell. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on agar. (≈ 1 × 1.05 µm)
Pyrococcus furiosus — Hyperthermophile growing at 100 °C; source of Pfu polymerase. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on agar. (≈ 1.43 µm)
Thermococcus kodakarensis — Hyperthermophilic coccus from deep-sea vents. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on agar. (≈ 1.3 µm)
Nitrosopumilus maritimus — Ammonia-oxidising marine archaeon. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on agar. (≈ 0.79 × 0.21 µm)
Thermoplasma acidophilum — Wall-less thermoacidophilic archaeon. Choose the view: the cells in 3-D, a stained smear (Gram stain) or colonies on agar. (≈ 1.68 × 1.26 µm)

Microscopy · Stains & smears 7

Gram stain — smear — A smear seen down the microscope at ×1000 after Gram stain. Choose the organism. (field ≈ 20 µm (×1000, oil))
Ziehl–Neelsen (acid-fast) stain — smear — A smear seen down the microscope at ×1000 after Ziehl–Neelsen (acid-fast) stain. Choose the organism. (field ≈ 20 µm (×1000, oil))
Dark-field microscopy — smear — A smear seen down the microscope at ×1000 after dark-field microscopy. Choose the organism. (field ≈ 20 µm (×1000, oil))
Giemsa stain — smear — A smear seen down the microscope at ×1000 after Giemsa stain. Choose the organism. (field ≈ 20 µm (×1000, oil))
Spore stain — smear — A smear seen down the microscope at ×1000 after spore stain. Choose the organism. (field ≈ 20 µm (×1000, oil))
India-ink capsule stain — smear — A smear seen down the microscope at ×1000 after India-ink capsule stain. Choose the organism. (field ≈ 20 µm (×1000, oil))
Lactophenol cotton blue mount — A tease mount of a mould in lactophenol cotton blue, the standard way to identify fungi by their spore-bearing structures. Choose the fungus. (field ≈ 100 µm)

Culture plates 41

Nutrient agar plate — General-purpose medium for non-fastidious bacteria. Choose the organism to see its typical colonies, or leave the plate uninoculated. (plate ⌀ 90 mm)
LB agar plate — Lysogeny broth agar — the standard for E. coli in molecular biology. Choose the organism to see its typical colonies, or leave the plate uninoculated. (plate ⌀ 90 mm)
Tryptic soy agar plate — Rich general-purpose medium. Choose the organism to see its typical colonies, or leave the plate uninoculated. (plate ⌀ 90 mm)
Blood agar (5% sheep) plate — Enriched medium that shows haemolysis: β (clear), α (green) or γ (none). Choose the organism to see its typical colonies, or leave the plate uninoculated. (plate ⌀ 90 mm)
Chocolate agar plate — Heated blood agar releasing X and V factors for Haemophilus and Neisseria. Choose the organism to see its typical colonies, or leave the plate uninoculated. (plate ⌀ 90 mm)
MacConkey agar plate — Selects Gram-negatives; lactose fermenters are pink, non-fermenters pale. Choose the organism to see its typical colonies, or leave the plate uninoculated. (plate ⌀ 90 mm)
EMB agar plate — Eosin–methylene blue; E. coli gives a green metallic sheen. Choose the organism to see its typical colonies, or leave the plate uninoculated. (plate ⌀ 90 mm)
XLD agar plate — Xylose–lysine–deoxycholate: Salmonella red with black (H₂S) centres, Shigella red, E. coli yellow. Choose the organism to see its typical colonies, or leave the plate uninoculated. (plate ⌀ 90 mm)
Hektoen enteric agar plate — Salmonella blue-green with black centres, Shigella green, fermenters orange. Choose the organism to see its typical colonies, or leave the plate uninoculated. (plate ⌀ 90 mm)
SS agar plate — Salmonella–Shigella agar. Choose the organism to see its typical colonies, or leave the plate uninoculated. (plate ⌀ 90 mm)
Mannitol salt agar plate — 7.5% salt selects staphylococci; S. aureus ferments mannitol and turns it yellow. Choose the organism to see its typical colonies, or leave the plate uninoculated. (plate ⌀ 90 mm)
Baird–Parker agar plate — S. aureus gives black colonies with a clear halo. Choose the organism to see its typical colonies, or leave the plate uninoculated. (plate ⌀ 90 mm)
Cetrimide agar plate — Selects Pseudomonas aeruginosa, which turns it green. Choose the organism to see its typical colonies, or leave the plate uninoculated. (plate ⌀ 90 mm)
King's B agar plate — Shows the fluorescent pigment of Pseudomonas under UV. Choose the organism to see its typical colonies, or leave the plate uninoculated. (plate ⌀ 90 mm)
Mueller–Hinton agar plate — Standard medium for antibiotic susceptibility testing. Choose the organism to see its typical colonies, or leave the plate uninoculated. (plate ⌀ 90 mm)
TCBS agar plate — Selects vibrios: sucrose fermenters yellow (V. cholerae), others green. Choose the organism to see its typical colonies, or leave the plate uninoculated. (plate ⌀ 90 mm)
Marine agar plate — Sea-salt medium for marine bacteria. Choose the organism to see its typical colonies, or leave the plate uninoculated. (plate ⌀ 90 mm)
Thayer–Martin agar plate — Selective chocolate agar for N. gonorrhoeae and N. meningitidis. Choose the organism to see its typical colonies, or leave the plate uninoculated. (plate ⌀ 90 mm)
BCYE agar plate — Buffered charcoal yeast extract — the only routine medium for Legionella. Choose the organism to see its typical colonies, or leave the plate uninoculated. (plate ⌀ 90 mm)
Regan–Lowe agar plate — Charcoal–blood medium for Bordetella pertussis. Choose the organism to see its typical colonies, or leave the plate uninoculated. (plate ⌀ 90 mm)
CCDA (Campylobacter) agar plate — Charcoal-based selective medium for Campylobacter, incubated microaerobically at 42 °C. Choose the organism to see its typical colonies, or leave the plate uninoculated. (plate ⌀ 90 mm)
Columbia blood agar (microaerobic) plate — Rich blood medium for Helicobacter and other fastidious organisms. Choose the organism to see its typical colonies, or leave the plate uninoculated. (plate ⌀ 90 mm)
Tellurite blood agar plate — Corynebacterium diphtheriae reduces tellurite to give black colonies. Choose the organism to see its typical colonies, or leave the plate uninoculated. (plate ⌀ 90 mm)
MRS agar plate — de Man–Rogosa–Sharpe medium for lactic acid bacteria. Choose the organism to see its typical colonies, or leave the plate uninoculated. (plate ⌀ 90 mm)
Anaerobic blood agar plate — Pre-reduced blood agar incubated in an anaerobic jar. Choose the organism to see its typical colonies, or leave the plate uninoculated. (plate ⌀ 90 mm)
BBE agar plate — Bacteroides bile–esculin: B. fragilis group gives black colonies. Choose the organism to see its typical colonies, or leave the plate uninoculated. (plate ⌀ 90 mm)
CCFA agar plate — Cycloserine–cefoxitin–fructose agar for C. difficile (yellow ground-glass colonies). Choose the organism to see its typical colonies, or leave the plate uninoculated. (plate ⌀ 90 mm)
Egg-yolk agar plate — Shows lecithinase (opaque halo) and lipase (pearly layer) of clostridia. Choose the organism to see its typical colonies, or leave the plate uninoculated. (plate ⌀ 90 mm)
PALCAM agar plate — Selective Listeria medium; esculin hydrolysis blackens it. Choose the organism to see its typical colonies, or leave the plate uninoculated. (plate ⌀ 90 mm)
ALOA (Listeria chromogenic) agar plate — L. monocytogenes forms blue-green colonies with an opaque halo. Choose the organism to see its typical colonies, or leave the plate uninoculated. (plate ⌀ 90 mm)
Bile–esculin agar plate — Enterococci hydrolyse esculin and blacken the medium. Choose the organism to see its typical colonies, or leave the plate uninoculated. (plate ⌀ 90 mm)
Löwenstein–Jensen medium plate — Egg-based green slant for mycobacteria. Choose the organism to see its typical colonies, or leave the plate uninoculated. (plate ⌀ 90 mm)
Middlebrook 7H10 agar plate — Clear agar for mycobacterial colony morphology. Choose the organism to see its typical colonies, or leave the plate uninoculated. (plate ⌀ 90 mm)
ISP2 (yeast–malt) agar plate — Medium for Streptomyces sporulation and pigments. Choose the organism to see its typical colonies, or leave the plate uninoculated. (plate ⌀ 90 mm)
Yeast–mannitol agar plate — Medium for rhizobia (mucoid colonies). Choose the organism to see its typical colonies, or leave the plate uninoculated. (plate ⌀ 90 mm)
BG-11 agar plate — Mineral medium for cyanobacteria. Choose the organism to see its typical colonies, or leave the plate uninoculated. (plate ⌀ 90 mm)
PPLO (Mycoplasma) agar plate — Serum-enriched medium; mycoplasma colonies look like fried eggs under the microscope. Choose the organism to see its typical colonies, or leave the plate uninoculated. (plate ⌀ 90 mm)
Halophile agar (25% NaCl) plate — High-salt medium for haloarchaea. Choose the organism to see its typical colonies, or leave the plate uninoculated. (plate ⌀ 90 mm)
CLED agar plate — Urine culture medium: lactose fermenters yellow, Proteus does not swarm. Choose the organism to see its typical colonies, or leave the plate uninoculated. (plate ⌀ 90 mm)
Sabouraud dextrose agar plate — The classic fungal culture medium. Choose the fungus to see its colony: texture, surface colour and the colour of the reverse. (plate ⌀ 90 mm)
CHROMagar Candida plate — Chromogenic agar that tells Candida species apart by colony colour (C. albicans green, C. tropicalis blue, C. krusei pink…). (plate ⌀ 90 mm)

Fungi · Yeasts 23

Candida albicans — The commonest fungal pathogen: thrush, vaginitis, invasive candidiasis; forms germ tubes. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar or its colour on CHROMagar Candida. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Candida glabrata — Small yeast without pseudohyphae; often azole-resistant (Nakaseomyces glabratus). Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar or its colour on CHROMagar Candida. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Candida tropicalis — Candida tropicalis, a fungus (yeasts). Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar or its colour on CHROMagar Candida. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Candida parapsilosis — Catheter-associated yeast of neonates. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar or its colour on CHROMagar Candida. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Candida krusei — Intrinsically fluconazole-resistant (Pichia kudriavzevii). Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar or its colour on CHROMagar Candida. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Candida auris — Emerging multidrug-resistant hospital yeast. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar or its colour on CHROMagar Candida. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Candida dubliniensis — Candida dubliniensis, a fungus (yeasts). Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar or its colour on CHROMagar Candida. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Candida lusitaniae — Candida lusitaniae, a fungus (yeasts). Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar or its colour on CHROMagar Candida. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Candida guilliermondii — Candida guilliermondii, a fungus (yeasts). Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar or its colour on CHROMagar Candida. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Cryptococcus neoformans — Encapsulated yeast of meningitis in AIDS; India-ink halo. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Cryptococcus gattii — Cryptococcus gattii, a fungus (yeasts). Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Saccharomyces cerevisiae — Baker's and brewer's yeast; the eukaryotic model organism. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Schizosaccharomyces pombe — Fission yeast: a model of the cell cycle. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Komagataella phaffii — Pichia pastoris, a protein-expression host. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Kluyveromyces lactis — Kluyveromyces lactis, a fungus (yeasts). Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Yarrowia lipolytica — Oleaginous yeast for lipid production. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Rhodotorula mucilaginosa — Salmon-pink carotenoid yeast. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Malassezia furfur — Lipid-dependent skin yeast of pityriasis versicolor ("spaghetti and meatballs"). Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Trichosporon asahii — Trichosporon asahii, a fungus (yeasts). Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Geotrichum candidum — Arthroconidia-forming yeast-like fungus of cheese rinds. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Debaryomyces hansenii — Debaryomyces hansenii, a fungus (yeasts). Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Zygosaccharomyces rouxii — Zygosaccharomyces rouxii, a fungus (yeasts). Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Brettanomyces bruxellensis — Wine and beer spoilage yeast. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)

Fungi · Moulds · Aspergillus 9

Aspergillus fumigatus — Blue-green velvety colonies; invasive aspergillosis. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Aspergillus flavus — Yellow-green; makes aflatoxin. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Aspergillus niger — Black "pepper" colonies; citric acid production. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Aspergillus terreus — Cinnamon-brown; source of lovastatin. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Aspergillus nidulans — Green with a purple reverse; a genetic model. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Aspergillus oryzae — Koji mould for soy sauce and sake. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Aspergillus versicolor — Aspergillus versicolor, a fungus (moulds · aspergillus). Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Aspergillus clavatus — Aspergillus clavatus, a fungus (moulds · aspergillus). Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Aspergillus ochraceus — Aspergillus ochraceus, a fungus (moulds · aspergillus). Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)

Fungi · Moulds · Penicillium 7

Penicillium chrysogenum — The penicillin producer (P. rubens); yellow exudate drops. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Penicillium roqueforti — Blue cheese mould. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Penicillium camemberti — White rind of Camembert and Brie. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Penicillium digitatum — Green mould of citrus. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Penicillium expansum — Blue mould of apples; makes patulin. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Penicillium citrinum — Penicillium citrinum, a fungus (moulds · penicillium). Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Penicillium griseofulvum — Source of griseofulvin. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)

Fungi · Dimorphic fungi 7

Talaromyces marneffei — Dimorphic fungus with a diffusible red pigment; infects people with HIV in SE Asia. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Histoplasma capsulatum — Bird and bat droppings; tuberculate macroconidia at 25 °C, tiny yeasts in macrophages at 37 °C. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Blastomyces dermatitidis — Broad-based budding yeast at 37 °C. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Coccidioides immitis — Valley fever; spherules full of endospores in tissue. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Coccidioides posadasii — Coccidioides posadasii, a fungus (dimorphic fungi). Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Paracoccidioides brasiliensis — "Pilot's wheel" multiple budding yeast. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Sporothrix schenckii — Rose-gardener's disease; rosette conidia. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)

Fungi · Moulds · Mucorales 7

Rhizopus stolonifer — Black bread mould; fills the plate in a day ("lid lifter"). Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Rhizopus arrhizus — Commonest cause of mucormycosis. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Mucor circinelloides — Mucor circinelloides, a fungus (moulds · mucorales). Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Mucor racemosus — Mucor racemosus, a fungus (moulds · mucorales). Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Lichtheimia corymbifera — Lichtheimia corymbifera, a fungus (moulds · mucorales). Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Cunninghamella bertholletiae — Cunninghamella bertholletiae, a fungus (moulds · mucorales). Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Rhizomucor pusillus — Rhizomucor pusillus, a fungus (moulds · mucorales). Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)

Fungi · Moulds · Fusarium 5

Fusarium solani — Keratitis and onychomycosis; banana-shaped macroconidia. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Fusarium oxysporum — Wilt of tomato and banana (Panama disease); purple reverse. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Fusarium graminearum — Head blight of wheat; makes deoxynivalenol. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Fusarium verticillioides — Maize pathogen; makes fumonisins. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Fusarium proliferatum — Fusarium proliferatum, a fungus (moulds · fusarium). Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)

Fungi · Moulds · dematiaceous 9

Alternaria alternata — Dark mould with chains of muriform conidia; an allergen. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Cladosporium cladosporioides — The commonest airborne mould. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Curvularia lunata — Curved, septate conidia. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Exophiala dermatitidis — Black yeast. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Fonsecaea pedrosoi — Chromoblastomycosis. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Aureobasidium pullulans — Black yeast producing pullulan. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Stachybotrys chartarum — "Toxic black mould" of damp buildings. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Epicoccum nigrum — Epicoccum nigrum, a fungus (moulds · dematiaceous). Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Chaetomium globosum — Chaetomium globosum, a fungus (moulds · dematiaceous). Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)

Fungi · Moulds · hyaline 11

Scedosporium apiospermum — Scedosporium apiospermum, a fungus (moulds · hyaline). Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Lomentospora prolificans — Lomentospora prolificans, a fungus (moulds · hyaline). Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Paecilomyces variotii — Paecilomyces variotii, a fungus (moulds · hyaline). Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Purpureocillium lilacinum — Purpureocillium lilacinum, a fungus (moulds · hyaline). Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Acremonium strictum — Acremonium strictum, a fungus (moulds · hyaline). Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Scopulariopsis brevicaulis — Scopulariopsis brevicaulis, a fungus (moulds · hyaline). Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Trichoderma reesei — Industrial cellulase producer. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Trichoderma harzianum — Biocontrol fungus. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Beauveria bassiana — Insect-killing fungus used as a biopesticide. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Metarhizium anisopliae — Green muscardine insect pathogen. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Neurospora crassa — Orange bread mould; the "one gene–one enzyme" model. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)

Fungi · Plant-pathogenic fungi 6

Botrytis cinerea — Grey mould; "noble rot" of wine grapes. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Sclerotinia sclerotiorum — Sclerotinia sclerotiorum, a fungus (plant-pathogenic fungi). Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Magnaporthe oryzae — Rice blast fungus. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Verticillium dahliae — Verticillium dahliae, a fungus (plant-pathogenic fungi). Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Colletotrichum gloeosporioides — Anthracnose of fruit. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Ustilago maydis — Corn smut; a model basidiomycete. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)

Fungi · Dermatophytes 10

Trichophyton rubrum — Athlete's foot and nail infection; red reverse. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Trichophyton mentagrophytes — Trichophyton mentagrophytes, a fungus (dermatophytes). Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Trichophyton interdigitale — Trichophyton interdigitale, a fungus (dermatophytes). Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Trichophyton tonsurans — Scalp ringworm (tinea capitis). Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Trichophyton verrucosum — Cattle ringworm. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Trichophyton violaceum — Trichophyton violaceum, a fungus (dermatophytes). Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Microsporum canis — Cat and dog ringworm; spindle macroconidia; yellow reverse. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Nannizzia gypsea — Soil dermatophyte (formerly M. gypseum). Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Microsporum audouinii — Microsporum audouinii, a fungus (dermatophytes). Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Epidermophyton floccosum — Club-shaped macroconidia only. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)

Fungi · Other fungi 2

Pneumocystis jirovecii — Pneumonia in immunocompromised patients; cannot be cultured. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount. (structures ≈ 2–100 µm; plate ⌀ 90 mm)
Batrachochytrium dendrobatidis — Chytrid killing amphibians worldwide. Choose the view: microscopic structures in 3-D, a lactophenol cotton blue mount, the colony on Sabouraud agar. (structures ≈ 2–100 µm; plate ⌀ 90 mm)