| Oblongichytrium sp. | 102618, 110833, 110834, 110835, 110836, 110837, 110838, 110839, 110840, 110841, 110842, 110843, 111925, 111926, 111927, 111928, 111929, 111930, 111931, 111932, 111933, 111934, 112216, 112221, 112223, 112225, 112227, 112728, 112729, 116175 |
| Oblongisporothyrium castanopsidis | 9262, 9263T |
| Occultifur kilbournensis | 112835T |
| Occultifur tropicalis | 109696T |
| Oceanicaulis sp. | 101722 |
| Oceanicoccus sagamiensis | 107125T |
| Oceanicola sp. | 111008, 111009 |
| Oceanimonas doudoroffii | 103032T |
| Oceaniserpentilla sp. | 116188 |
| Oceanisphaera arctica | 106171T |
| Oceanisphaera sp. | 102020 |
| Oceanithermus desulfurans | 100063T |
| Oceanithermus profundus | 100410T |
| Oceanobacillus aidingensis | 105904T |
| Oceanobacillus gochujangensis | 109637T |
| Oceanobacillus manasiensis | 105903T |
| Oceanobacillus sojae | 105379T |
| Oceanobacillus sp. | 114664, 114665 |
| Oceanobacter kriegii | 15467T |
| Oceanobacterium insulare | 102018 |
| Oceanospirillum beijerinckii | 13612, 15445T |
| Oceanospirillum linum | 15448T, 15449 |
| Oceanospirillum maris | 13616, 15468T |
| Oceanospirillum multiglobuliferum | 13614T |
| Ochroconis musae | 113466, 113470, 114592 |
| Ochromonas sp. (class: Chrysophyceae) | 111011 |
| Ochrosphaera sp. (class: Haptophyceae) | 102811, 102915, 102916, 103018 |
| Oecophyllibacter saccharovorans | 113641, 113642, 113643T |
| Oedocephalum coprophilum | 7073 |
| Oedocephalum glomerulosum | 7805 |
| Oedocephalum nayoroense | 32546T |
| Oenococcus kitaharae | 113254T |
| Oenococcus oeni | 100497T, 109605, 109606 |
| Oerskovia enterophila | 14295T, 14296 |
| Oerskovia jenensis | 15012T |
| Oerskovia paurometabola | 106154T |
| Oerskovia turbata | 15014, 15015T |
| Oerskovia turbata phage O2 | 20066 |
| Oerskovia turbata phage O3 | 20069 |
| Oerskovia turbata phage O6 | 20067 |
| Ogataea chonburiensis | 101965T |
| Ogataea corticis | 1794T |
| Ogataea dorogensis | 101078T |
| Ogataea glucozyma | 1472T |
| Ogataea henricii | 1477T, 1478 |
| Ogataea kanchanaburiensis | 108603T |
| Ogataea kodamae | 10090T |
| Ogataea methylovora | 1910, 10705T |
| Ogataea minuta var. minuta | 0975T, 10402, 10746 |
| Ogataea minuta var. nonfermentans | 1473T |
| Ogataea nakhonphanomensis | 101966T |
| Ogataea paradorogensis | 100260, 100261T, 100262 |
| Ogataea philodendra | 1821T |
| Ogataea philodendri | 115891 |
| Ogataea phyllophila | 107780T |
| Ogataea pini | 1342T, 1793, 1795 |
| Ogataea polymorpha | 0799, 1024, 1071, 1475, 1476T, 101498, 101499, 101500, 101501, 101502 |
| Ogataea sp. | 111447, 111448 |
| Ogataea thermomethanolica | 101504, 113734, 113735, 113736, 113737, 113738, 113739, 113740, 113741, 113742, 113743, 113744, 113745 |
| Ogataea trehaloabstinens | 101075T, 101076 |
| Ogataea wangdongensis | 107778T, 107779 |
| Ogataea wickerhamii | 1706T |
| Ogataea zsoltii | 101079T |
| Oharaeibacter diazotrophicus | 111955T |
| Oidiodendron atrovirens | 116733 |
| Oidiodendron boninense | 115392T, 115413 |
| Oidiodendron chlamydosporicum | 100848, 111203, 115393 |
| Oidiodendron citrinum | 9338 |
| Oidiodendron echinulatum | 31963 |
| Oidiodendron eucalypti | 115396, 115397 |
| Oidiodendron griseum | 32265, 100453 |
| Oidiodendron maius | 115398, 115399, 115400 |
| Oidiodendron maius var. maius | 104491 |
| Oidiodendron mellicola | 115401 |
| Oidiodendron pilicola | 115402 |
| Oidiodendron rhodogenum | 115391 |
| Oidiodendron setiferum | 33245 |
| Oidiodendron sp. | 104492, 104493, 104494, 104495, 104498, 104499, 104500, 104501, 104502, 104503, 104504, 104505, 104506, 104507, 104508, 104509, 104510 |
| Oidiodendron tenuissimum | 6798, 104511, 115410 |
| Oidiodendron tokumasui | 115411T, 115412 |
| Oidiodendron truncatum | 9951, 31812, 100849 |
| Okibacterium fritillariae | 16404T, 16407 |
| Oleiagrimonas soli | 110685T |
| Oleibacter marinus | 105758, 105759, 105760T |
| Oligella urethralis | 14589T |
| Oligophagozyma castellii | 10270T |
| Olleya sediminilitoris | 114500T |
| Olleya sp. | 111518 |
| Olsenella sp. | 116429, 116430 |
| Oltmannsiellopsis geminata (class: Ulvophyceae) | 103011 |
| Oltmannsiellopsis sp. (class: Ulvophyceae) | 102800 |
| Omphalotus guepiniiformis | 4931, 6992, 8341, 8342, 8616, 8765, 8917, 8918, 104980 |
| Onnia orientalis | 30386 |
| Onygena corvina | 9684, 31784 |
| Onygena equina | 31785 |
| Oospora astringenes | 7001 |
| Oospora aurantia | 4606 |
| Oospora sulphurea-ochracea | 4608 |
| Oospora viscosa | 4604 |
| Oosporidium margaritiferum | 1208T, 1688 |
| Ophidiomyces ophidiicola | 114438, 114439 |
| Ophiobolus herpotrichus | 6132, 6158 |
| Ophioceras commune | 33290 |
| Ophiocordyceps agriotis | 101737 |
| Ophiocordyceps annulata | 101738, 106951 |
| Ophiocordyceps appendiculata | 106959, 106960 |
| Ophiocordyceps arborescens | 105890, 105891T |
| Ophiocordyceps brunneipunctata | 101396 |
| Ophiocordyceps cf. agriotis | 108985, 108986, 108987, 108988 |
| Ophiocordyceps cf. sessilis | 110394 |
| Ophiocordyceps citrina | 109326 |
| Ophiocordyceps clavata | 106961, 106962 |
| Ophiocordyceps coccidiicola | 100682, 100683 |
| Ophiocordyceps cochlidiicola | 106963 |
| Ophiocordyceps dipterigena | 101397, 101398, 101431, 109005, 109006 |
| Ophiocordyceps ferruginosa | 101743 |
| Ophiocordyceps formicarum | 101744, 101745 |
| Ophiocordyceps irangiensis | 101399, 101400, 101401, 101430 |
| Ophiocordyceps jinggangshanensis | 111627 |
| Ophiocordyceps longissima | 106965, 108989 |
| Ophiocordyceps macroacicularis | 100685T, 105888, 105889 |
| Ophiocordyceps melolonthae | 101747 |
| Ophiocordyceps myrmecophila | 101402 |
| Ophiocordyceps nutans | 100944, 101749 |
| Ophiocordyceps odonatae | 33274, 106941 |
| Ophiocordyceps pentatomae | 113391 |
| Ophiocordyceps rubiginosiperitheciata | 100946, 106966 |
| Ophiocordyceps sessilis | 105893, 108983 |
| Ophiocordyceps sobolifera | 106967, 114805 |
| Ophiocordyceps sp. | 108984, 110395, 113216, 113217, 113218 |
| Ophiocordyceps sphecocephala | 101414, 101415, 101416, 101417, 101432, 101433, 101434, 101435, 101436, 101752, 101753 |
| Ophiocordyceps stylophora | 100947, 100948, 100949 |
| Ophiocordyceps tricentri | 106968, 106969 |
| Ophiocordyceps variabilis | 114962 |
| Ophiostoma abieticola | 105449T |
| Ophiostoma aoshimae | 104092 |
| Ophiostoma bicolor | 8666 |
| Ophiostoma brunneociliatum | 104093 |
| Ophiostoma canum | 105827 |
| Ophiostoma cf. breviusculum | 105441 |
| Ophiostoma cf. neglectum | 105448, 105451 |
| Ophiostoma davidsonii | 104099, 104100 |
| Ophiostoma floccosum | 104094, 104095 |
| Ophiostoma ips | 8665 |
| Ophiostoma japonicum | 105456T |
| Ophiostoma koreanum | 104101 |
| Ophiostoma microcarpum | 104096 |
| Ophiostoma minus | 8664, 104998, 104999 |
| Ophiostoma piceae | 7644, 8662, 104097, 104098 |
| Ophiostoma piliferum | 6702 |
| Ophiostoma pluriannulatum | 8663 |
| Ophiostoma quercus | 105452 |
| Ophiostoma rectangulosporium | 105440 |
| Ophiostoma sp. | 105442, 105443, 105444, 105445, 105446, 105447, 105450, 105453 |
| Ophiostoma sugadairense | 111723T |
| Ophiostoma ulmi | 6128 |
| Orbicula parietina | 9491 |
| Orbilia xanthostigma | 9521 |
| Orbimyces spectabilis | 7835, 32157, 32158 |
| Orbiocrella petchii | 101471, 101472 |
| Ordus tribrachiatus | 111152T, 111153 |
| Ornithinibacillus gellani | 113552T |
| Ornithinicoccus hortensis | 16434T |
| Ornithinimicrobium cerasi | 113522T |
| Ornithinimicrobium flavum | 109452T |
| Ornithinimicrobium humiphilum | 106159T |
| Oryzihumus leptocrescens | 100762T |
| Oryzihumus soli | 111450T |
| Oryzihumus terrae | 109596T |
| Oryzobacter terrae | 109598T |
| Oryzomonas japonicum | 114286T |
| Oryzomonas sagensis | 114287T |
| Oscillibacter ruminantium | 108824T |
| Oscillibacter valericigenes | 101213T |
| Osmozyma mogii | 0436T |
| Ostreococcus sp. (class: Prasinophyceae) | 102845 |
| Ottowia flava | 113500T |
| Ottowia oryzae | 113109T |
| Oudemansiella canarii | 31216 |
| Oudemansiella mucida | 9784 |
| Oudemansiella radicata var. furfuracea | 101637 |
| Oudemansiella venosolamellata | 104979 |
| Ovulinia azaleae | 6610 |
| Oxalicibacterium horti | 13594T |
| Oxalicibacterium solurbis | 102665T |
| Oxalicibacterium sp. | 114320 |
| Oxydothis nypae | 32218 |