- 625 items
- Aa
{{taxon|genus|family|Orchidaceae|a group of [[orchid]]s of cool climates in Latin America}}
{{taxon|subgenus|family|Euconulidae|{{taxlink|Philonesia (Aa)|subgenus}}, a group of [[snail]]s}}
- Abranchia
{{taxon|order|class|Gastropoda|somewhat similar to the order [[Nudibranchia]]}}
{{taxon|order|phylum|Annelida|[[annelid]]s that lacked specialized respiratory systems, the [[Oligochaeta]], including [[earthworm]]s}}
- Abronia
{{taxon|genus|family|Nyctaginaceae|North American [[herb]]s with fragrant flowers}}
{{taxon|genus|family|Anguidae|{{vern|arboreal alligator lizard|pl=s}}}}
- Abrus
{{taxon|genus|family|Fabaceae|tropical vines, with purple flowers and [[pinnate]] leaves}}
{{taxon|genus|family|Cicadellidae|certain [[hopper]]s}}
- Acalepha
{{taxon|class|division|Radiata|a group of [[coelenterate]]s including the [[jellyfish]] and [[sea nettle]]s}}
{{taxon|genus|subclass|Hexacorallia|certain extinct [[coral]]s}}
- Acanthella
{{taxon|genus|family|{{taxlink|Dictyonellidae|family}}|certain [[sponge]]s}}
{{taxon|genus|family|Melastomataceae|two among the very many species of [[melastome]]s, flowering plants of tropical South America}}
- Acanthocephala
{{taxon|phylum|superphylum|Spiralia|[[intestinal]] worms that have a [[proboscis]] armed with [[recurved]] spines}}
{{taxon|genus|family|Coreidae|[[leaf-footed bug]]s}}
- Acanthocephalus
{{taxon|genus|family|Asteraceae|[[aster]]-like plants native to Central Asia}}
{{taxon|genus|family|{{taxlink|Echinorhynchidae|family}}|certain [[parasitic]] [[worm]]s}}
- Acca
{{taxon|genus|family|Myrtaceae|[[feijoa]] or [[pineapple guava]] and closely related shrubs of South America}}
{{taxon|genus|family|Nymphalidae|sometimes including in genus {{taxlink|Pantoporia|genus}}}}
- Acidobacteria
{{taxon|phylum|kingdom|Bacteria|[[acidophilic]] [[bacteria]], sometimes {{taxlink|Acidobacteriia|phylum}}, now ''[[Acidobacteriota]]''|i=1}}
{{taxon|class|phylum|Acidobacteriota|i=1}}
- Acoela
{{taxon|order|class|Turbellaria}}
{{taxon|class|phylum|Xenacoelomorpha}}
- Acrocephalus
{{taxon|genus|family|Acrocephalidae}}
{{taxon|genus|family|Lamiaceae|now {{taxlink|Platostoma|genus}}}}
- Actaea
{{taxon|genus|family|Ranunculaceae|[[baneberry]] or [[bugbane]], flowering plants native to temperate regions of the Northern Hemisphere}}
{{taxon|genus|family|{{taxlink|Xanthidae|family}}|various [[mud crab]]s}}
- Actinaria
{{taxon|order|subclass|Hexacorallia}}
{{taxon|suborder|order|Anthozoa|}}
- Actinopterygii
{{taxon|class|superclass|Osteichthyes}}
{{taxon|superclass|infraphylum|Gnathostomata}}
- Adelia
{{taxon|genus|family|Euphorbiaceae|various [[spurge]]s}}
{{taxon|genus|family|Cicadidae|various [[cicada]]s}}
- Adelphia
{{taxon|genus|family|Malpighiaceae|woody [[vine]]s, native to the tropical and subtropical Americas}}
{{taxon|genus|family|Pyralidae|a single species of [[snout moth]]}}
- Aegilops
{{taxon|genus|family|Poaceae|the [[goatgrass]]es}}
{{taxon|genus|order|{{taxlink|Arcoida|order}}|extinct [[ark shell]]s}}
- Agathis
{{taxon|genus|family|Araucariaceae|certain ancient [[conifer]]s, called [[kauri]] or [[dammara]], native to southeast Asia, especially Indonesia}}
{{taxon|genus|family|Braconidae|certain [[parasitic]] [[wasp]]s}}
- Aglaomorpha
{{taxon|genus|family|Erebidae|certain moths}}
{{taxon|genus|family|Polypodiaceae|certain ferns}}
- Aglossa
{{taxon|order|class|Amphibia|certain tongueless, tailless [[toad]]s}}
{{taxon|genus|family|Pyralidae|certain [[moth]]s}}
- Agnatha
{{taxon|superclass|subphylum|Vertebrata}}
{{taxon|infraphylum|subphylum|Vertebrata}}
- Alaria
{{taxon|genus|family|{{taxlink|Alariaceae|family}}|certain [[brown alga]]e}}
{{taxon|genus|family|{{taxlink|Diplostomatidae|family}}|certain [[flatworm]]s}}
- Alectoria
{{taxon|genus|family|Tettigoniidae|bush crickets or katydids}}
{{taxon|genus|family|Parmeliaceae|fruticose lichens}}
- Aloe
{{taxon|genus|family|Xanthorrhoeaceae}}
{{taxon|genus|family|Asphodelaceae}}
- Alsophila
{{taxon|genus|family|Cyatheaceae|certain [[tree fern]]s}}
{{taxon|genus|family|Geometridae|certain [[moth]]s}}
- Alveolata
{{taxon|superphylum|subkingdom|Biciliata}}
{{taxon|superphylum|infrakingdom|Halvaria}}
- Amblycera
{{taxon|suborder|order|Phthiraptera}}
{{taxon|suborder|order|Psocodea}}
- Ammophila
{{taxon|genus|family|Poaceae|many [[beachgrass]]es}}
{{taxon|genus|family|Sphecidae|some [[sand wasp]]s and others}}
- Amoebozoa
{{taxon|phylum|kingdom|Protista}}
{{taxon|phylum|subkingdom|Sarcomastigota}}
- Amorpha
{{taxon|genus|family|Fabaceae|{{vern|false indigo|false indigos}}, plants whose flowers lack the wing and keel petals typical of other members of the [[Faboideae]]}}
{{taxon|genus|family|Sphingidae|certain [[moth]]s}}
- Amphisbaenia
{{taxon|suborder|order|Lacertoidea}}
{{taxon|superfamily|order|Squamata}}
- Amygdalus
{{taxon|genus|family|Rosaceae|the [[almond]]s and relatives}}
{{taxon|subgenus|family|Rosaceae|{{taxlink|Prunus subg. Amygdalus|subgenus}}}}
- Ancylostomatidae
{{taxon|family|order|Panagrolaimida}}
{{taxon|family|order|Strongylida}}
- Angiostrongylidae
{{taxon|family|order|Panagrolaimida}}
{{taxon|family|order|Strongylida}}
- Anguilliformes
{{taxon|order|superorder|Elopomorpha}}
{{taxon|order|class|Teleostei}}
- Animalia
{{taxon|kingdom|domain|Eukaryota}}
{{taxon|kingdom|superkingdom|Eukaryota}}
- Anisakidae
{{taxon|family|order|Spirurida}}
{{taxon|family|order|Rhabditida}}
- Annelida
{{taxon|phylum|superphylum|Protostomia}}
{{taxon|phylum|superphylum|Spiralia}}
- Annona
{{taxon|genus|family|Annonaceae|flowering plants, consisting of tropical [[shrub]]s and small trees, including the [[soursop]]}}
{{taxon|genus|family|Miridae|certain {{vern|capsid bug|pl=s}}}}
- Anthocerotophyta
{{taxon|division|kingdom|Plantae}}
{{taxon|phylum|superphylum|Embryophyta}}
- Anthophila
{{taxon|clade|order|Hymenoptera|[[bee]]s}}
{{taxon|genus|family|Choreutidae|certain [[moth]]s}}
- Anthozoa
{{taxon|class|phylum|Cnidaria}}
{{taxon|subphylum|phylum|Cnidaria}}
{{taxon|class|subphylum|Anthozoa}}
- Anticlea
{{taxon|genus|family|Geometridae|certain moths}}
{{taxon|genus|family|Melanthiaceae|certain plants}}
- Anura
{{taxon|order|subclass|Lissamphibia|[[frog]]s and [[toad]]s}}
{{taxon|genus|family|Asteraceae|now {{taxlink|Arctium sect. Anura|section}}}}
- Aotus
{{taxon|genus|family|Fabaceae|[[golden pea]]s}}
{{taxon|genus|family|{{taxlink|Aotidae|family}}|[[night monkey]]s}}
- Apatura
{{taxon|genus|family|Nymphalidae|now, any of four species of [[emperor butterfly|emperor butterflies]], formerly also including species now in genera {{taxlink|Mimathyma|genus}} and {{taxlink|Chitoria|genus}}}}
{{taxon|genus|family|Nymphalidae|{{vern|cracker butterfly|cracker butterflies}}, now included in genus {{taxlink|Hamadryas|genus|nomul=1}}}}
- Aphis
{{taxon|genus|family|Aphididae|typical [[aphid]]s}}
{{taxon|subgenus|family|Aphididae|{{taxlink|Aphis (Aphis)|subgenus}}}}
- Apicomplexa
{{taxon|subphylum|phylum|Myzozoa}}
{{taxon|infraphylum|subphylum|Myzozoa}}
- Aplacophora
{{taxon|class|phylum|Mollusca}}
{{taxon|clade|phylum|Mollusca}}
- Apoda
{{taxon|order|class|Amphibia|{{ll|mul|Gymnophiona}}, [[caecilian]]s, worm-like [[amphibian]]s}}
{{taxon|genus|family|Limacodidae|[[slug]]-like moths}}
- Aquificae
{{taxon|phylum|kingdom|Bacteria|[[bacteria]] that live in [[hot spring]]s and [[thermal]] ocean [[vent]]s etc., now ''{{taxlink|Aquificota|phylum}}''|i=1}}
{{taxon|class|phylum|{{taxlink|Aquificota|phylum}}|i=1}}
- Araucariaceae
{{taxon|family|order|Pinales}}
{{taxon|family|order|Cupressales}}
- Archaeognatha
{{taxon|subclass|class|Insecta}}
{{taxon|order|subclass|Monocondylia|the {{vern|jumping bristletail|pl=s}}}}
- Archezoa
{{taxon|kingdom|empire|Eukaryota}}
{{taxon|subkingdom|kingdom|Protozoa}}
{{taxon|superphylum|infrakingdom|Excavata|a group of [[primitive]] [[eukaryote]]s believed to have evolved before the origin of [[mitochondria]]}}
- Archiannelida
{{taxon|class|phylum|Annelida}}
{{taxon|order|class|Polychaeta}}
- Arenaria
{{taxon|genus|family|Scolopacidae|[[turnstone]]s, that forage for [[invertebrate]]s along sea coasts worldwide, notably under small stones}}
{{taxon|genus|family|Caryophyllaceae|[[sandwort]]s}}
- Argentina
{{taxon|genus|family|Argentinidae|{{vern|herring smelt|pl=s}}}}
{{taxon|genus|family|Rosaceae|[[silverweed]]s and, possibly, some typical [[cinquefoil]]s}}
- Articulata
{{taxon|subclass|class|Crinoidea|the surviving [[crinoid]]s, including [[feather star]]s and [[sea lily|sea lilies]]}}
{{taxon|suborder|order|Cyclostomatida|certain {{ll|mul|Bryozoa}}}}
{{taxon|division|subphylum|Brachiopoda|all groups with articulating hinges, approximately the same as the phylum {{taxlink|Rhynchonelliformea|subphylum}}}}
- Ascarididae
{{taxon|family|order|Spirurida}}
{{taxon|family|order|Rhabditida}}
- Ascaridoidea
{{taxon|superfamily|order|Spirurida}}
{{taxon|superfamily|order|Rhabditida}}
- Ascomycota
{{taxon|division|kingdom|Fungi}}
{{taxon|phylum|subkingdom|Dikarya}}
- Asparagaceae
{{taxon|family|order|Asparagales|several genera, including ''[[Asparagus]]'' and {{taxlink|Hemiphylacus|genus}}, now called [[Asparagoideae]]}}
{{taxon|family|order|Asparagales|many [[genus|genera]]}}
- Asta
{{taxon|genus|family|Brassicaceae|an herb found in Mexico, especially {{w|San Luis Potosi}}}}
{{taxon|genus|family|Noctuidae|certain moths, now {{taxlink|Avitta|genus}}}}
- Asterina
{{taxon|genus|family|Asterinidae|various [[starfish]]es}}
{{taxon|genus|family|Asterinaceae|various [[fungus|fungi]]}}
- Asterolepis
{{taxon|genus|family|Asterolepididae|extinct armored fishes}}
{{taxon|genus|family|Tortricidae|certain moths}}
- Asterozoa
{{taxon|superclass|subphylum|Eleutherozoa}}
{{taxon|subphylum|phylum|Echinodermata}}
- Atheriniformes
{{taxon|order|superorder|Acanthopterygii|}}
{{taxon|order|class|Teleostei}}
- Aulopiformes
{{taxon|order|superorder|Cyclosquamata}}
{{taxon|order|class|Teleostei}}
- Aurata
{{taxon|genus|family|Sparidae|''[[Calamus]]'', some [[porgy|porgies]]}}
{{taxon|genus|family|Sparidae|''[[Sparus]]'', etc., some [[sea bream]]s}}
- Austrobaileyales
{{taxon|order|class|Magnoliopsida}}
{{taxon|order|clade|angiosperms|diverging from other angiosperms about 130 Mya}}
- Aves
{{taxon|class|subphylum|Vertebrata}}
{{taxon|subclass|class|Reptilia}}
- Azalea
{{taxon|genus|family|Ericaceae}}
{{taxon|subgenus|family|Ericaceae|{{taxlink|Rhododenron subg. Azalea|subgenus}}, now {{taxlink|Rhododendron subg. Azaleastrum|subgenus}}}}
- BCV
{{taxon|species|genus|Coronavirus}}
{{taxon|species|genus|Circovirus}}
- Bacillus
{{taxon|genus|family|Bacillaceae|i=1|certain rod-shaped [[bacteria]]}}
{{taxon|genus|family|{{taxlink|Bacillidae|family}}|certain [[stick insect]]s}}
- Bacteroidetes
{{taxon|phylum|kingdom|Bacteria|i=1|now ''{{taxlink|Bacteriodota|phylum}}''}}
{{taxon|class|phylum|{{taxlink|Bacteriodota|phylum}}|i=1}}
- Balanophoreae
{{taxon|family|order|Santalales}}
{{taxon|order|class|{{taxlink|Rhizogens|class}}|in Lindley system}}
- Barbus
{{taxon|genus|family|{{taxlink|Barbidae|family}}|many fish resembling [[barb]]s and [[barbel]]s, now being assigned to genera, mostly in [[Barbinae]], especially {{taxlink|Puntius|genus}}}}
{{taxon|genus|family|Cyprinidae|typical [[barb]]s and [[barbel]]s}}
- Bartonella
{{taxon|genus|family|Rhizobiaceae|i=1}}
{{taxon|genus|family|Bartonellaceae|i=1}}
- Bartonia
{{taxon|genus|family|Gentianaceae|[[screwstem]]s}}
{{taxon|genus|family|{{taxlink|Loasaceae|family}}|now generally included in the genus ''{{ll|mul|Mentzelia}}'', [[blazingstar]]s or {{vern|stickleaf|pl=s}}}}
- Bartramia
{{taxon|genus|family|[[Bartramiaceae]]|certain [[moss]]es}}
{{taxon|genus|family|Scolopacidae|the [[upland sandpiper]], a migratory bird that breeds in much of Canada and the northern US}}
- Bassia
{{taxon|genus|family|Amaranthaceae|[[smotherweed]]s}}
{{taxon|genus|family|{{taxlink|Abylidae|family}}|a single species of [[bioluminescent]] [[hydrozoan]]s}}
- Batis
{{taxon|genus|family|Platysteiridae|[[sparrow]]-like birds of sub-Saharan Africa}}
{{taxon|genus|family|{{taxlink|Bataceae|family}}|salt-tolerant plants native to warm-temperate-to-tropical America and tropical Australasia; [[pickleweed]]}}
- Batrachoidiformes
{{taxon|order|superorder|Paracanthopterygii}}
{{taxon|order|class|Teleostei}}
- Bdelloidea
{{taxon|subclass|class|Eurotatoria|[[bdelloid]] [[rotifer]]s (that resemble [[leech]]es)}}
{{taxon|superfamily|order|Trombidiformes|various [[mite]]s}}
- Beggiatoa
{{taxon|genus|family|Beggiatoaceae|i=1}}
{{taxon|genus|family|Thiotrichaceae|i=1}}
- Belideus
{{taxon|subgenus|family|Petauridae|{{taxlink|Petaurus (Belideus)|subgenus}}, now recombined into ''{{l|mul|Petaurus}}''}}
{{taxon|genus|family|Petauridae|Now synonymized into ''{{l|mul|Petaurus}}''}}
- Beloniformes
{{taxon|order|class|Actinopterygii}}
{{taxon|order|class|Teleostei}}
- Beryciformes
{{taxon|order|class|Actinopterygii|the [[roughy|roughies]], [[flashlight fish]]es and [[squirrelfish]]es, and their close relatives}}
{{taxon|order|class|Teleostei|[[flashlight fish]], [[fangtooth]]s, [[whalefish]], and certain other closely related deepsea fish}}
- Beta
{{taxon|genus|family|Amaranthaceae|[[beet]]s}}
{{taxon|genus|family|Acrididae|now {{taxlink|Philbostroma|genus}}, certain [[grasshopper]]s}}
- Bilateria
{{taxon|subkingdom|kingdom|Animalia}}
{{taxon|clade|subkingdom|Eumetazoa}}
- Blastocystis
{{taxon|genus|kingdom|Fungi}}
{{taxon|genus|kingdom|Chromista}}
- Bombus
{{taxon|genus|family|Apidae|[[bumblebee]]s}}
{{taxon|subgenus|family|Apidae|{{taxlink|Bombus (Bombus)|subgenus}}}}
- Bonamia
{{taxon|genus|family|Convolvulaceae|[[lady's nightcap]]}}
{{taxon|genus|family|Haplosporiidae|certain protists}}
- Bonellia
{{taxon|genus|family|{{taxlink|Bonelliidae|family}}|certain [[spoon worm]]s}}
{{taxon|genus|family|{{taxlink|Eulimidae|family}}|certain snails}}
{{taxon|genus|family|Primulaceae|certain plants}}
- Bordetella
{{taxon|genus|family|{{taxlink|Burkholderiaceae|family}}|i=1}}
{{taxon|genus|family|{{taxlink|Alcaligenaceae|family}}|i=1}}
- Bos grunniens
{{taxon|species|family|Bovidae|domesticated [[yak]]}}
{{taxon|species|family|Bovidae|all [[yak]]s}}
- Bostrychia
{{taxon|genus|family|Threskiornithidae}}
{{taxon|genus|family|Rhodomelaceae}}
- Brucella
{{taxon|genus|family|Rhizobiaceae|i=1}}
{{taxon|genus|family|Brucellaceae|i=1}}
- Bryophyta
{{taxon|division|kingdom|Plantae}}
{{taxon|phylum|superphylum|Embryophyta}}
- Burmannia
{{taxon|genus|family|Burmanniaceae|certain flowering plants}}
{{taxon|genus|family|Crambidae|certain moths}}
- Byttnerioideae
{{taxon|subfamily|family|Malvaceae|several tribes of [[tropical]] [[flowering plant]]s, apparently not [[monophyletic]]}}
{{taxon|clade|clade|Byttneriina}}
- Caenogastropoda
{{taxon|superorder|subclass|Orthogastropoda}}
{{taxon|subclass|class|Gastropoda}}
- Calamus
{{taxon|genus|family|Sparidae|certain [[porgy|porgies]]}}
{{taxon|genus|family|Arecaceae|certain [[rattan]] palms}}
- Calliopsis
{{taxon|genus|family|Asteraceae|now {{taxlink|Coreopsis sect. Calliopsis|section}}}}
{{taxon|genus|family|Andrenidae|certain [[andrenid]] bees}}
- Calopteryx
{{taxon|genus|family|Calopterygidae|{{vern|jewelwing}}s, certain of the [[demoiselle]]s}}
{{taxon|genus|family|Ericaceae|{{synonym of|mul|{{taxlink|Thibaudia|genus}}}} ({{vern|zagalita|pl=s}})}}
- Canarium
{{taxon|genus|family|Burseraceae|various nut-bearing trees of [[Old World]] tropics and subtropics}}
{{taxon|genus|family|Strombidae|certain {{vern|true conch|pl=s}}}}
- Capillariidae
{{taxon|family|order|Trichocephalida}}
{{taxon|family|order|Trichinellida}}
- Capsella
{{taxon|genus|family|Brassicaceae|[[shepherd's purse]]}}
{{taxon|genus|family|Donacidae|[[mollusc]]s called [[bean clam]]s or [[wedge shell]]s}}
- Carex
{{taxon|genus|family|Cyperaceae|{{vern|true sedge|pl=s}}}}
{{taxon|section|family|Cyperaceae|{{taxlink|Carex sect. Carex|section}}}}
- Carinatae
{{taxon|subclass|class|Aves|Birds having a pronounced keel-like [[sternum]], to which muscles used in flight attach}}
{{taxon|clade|subclass|Aves|Birds descended from a certain common ancestral type of bird, possibly having a keel-like [[sternum]] and other bone-structure characteristics}}
- Caryophyllus
{{taxon|genus|family|Myrtaceae|including the [[clove]], now included in ''{{l|mul|Syzygium}}''}}
{{taxon|genus|family|Caryophyllaceae|now principally ''{{l|mul|Dianthus}}'', the [[clove pink]], which has a clove-like smell}}
- Catenulida
{{taxon|order|subphylum|Catenulidea}}
{{taxon|class|phylum|Platyhelminthes}}
- Cathartidae
{{taxon|family|order|Accipitriformes}}
{{taxon|family|order|{{taxlink|Cathartiformes|order}}}}
- Centrohelea
{{taxon|class|phylum|Heliozoa}}
{{taxon|class|phylum|{{taxlink|Haptista|phylum}}}}
- Cercozoa
{{taxon|phylum|supergroup|Rhizaria|many [[protist]]s}}
{{taxon|phylum|infrakingdom|Rhizaria|certain [[chromist]]s}}
- Cereus
{{taxon|genus|family|Cactaceae|certain columnar [[cactus]]es}}
{{taxon|genus|family|{{taxlink|Sagartiidae|family}}|certain [[sea anemone]]s}}
- Cestoda
{{taxon|class|phylum|Platyhelminthes}}
{{taxon|infraclass|class|Neoophora}}
- Cestoidea
{{taxon|order|phylum|Platyhelminthes|{{synonym of|mul|Cestoda|gloss=ranked as order}}}}
{{taxon|order|class|Cestoda}}
- Cestracion
{{taxon|genus|family|Heterodontidae|[[horn shark]]s, now included in genus ''[[Heterodontus]]''}}
{{taxon|genus|family|Sphyrnidae|[[hammerhead shark]]s, synonym of ''[[Sphyrna]]''}}
- Cetacea
{{taxon|order|class|Mammalia}}
{{taxon|infraorder|order|Artiodactyla}}
{{taxon|infraorder|order|Cetartiodactyla}}
- Chaetosiphon
{{taxon|genus|family|Aphididae|certain [[aphid]]s}}
{{taxon|genus|family|{{taxlink|Chaetosiphonaceae|family}}|certain [[green alga]]e}}
- Chamaepericlymenum
{{taxon|genus|family|Cornaceae}}
{{taxon|subgenus|family|Cornaceae|synonym of {{taxlink|Cornus subg. Arctocrania|subgenus}}}}
- Charophyta
{{taxon|division|kingdom|Plantae|including the [[stonewort]]s}}
{{taxon|superphylum|infrakingdom|Streptophyta}}
{{taxon|phylum|superphylum|Charophyta}}
- Chelonia
{{taxon|genus|family|Cheloniidae|[[green sea turtle]] (''[[Chelonia mydas]]'')}}
{{taxon|order|class|Reptilia|[[turtle]]s; {{synonym of|mul|Testudines|nocap=1}}}}
- Chelonii
{{taxon|order|class|Reptilia|synonym of [[Testudines]], the [[order]] of turtles}}
{{taxon|superfamily|order|Testudines|synonym of [[Chelonioidea]], the [[superfamily]] of sea turtles}}
{{taxon|family|order|Testudines|synonym of [[Cheloniidae]], a [[family]] of [[sea turtle]]}}
- Chione
{{taxon|genus|family|Veneridae|certain [[Venus clam]]s}}
{{taxon|genus|family|Rubiaceae|trees from the [[neotropics]]}}
- Chitonida
{{taxon|order|class|Polyplacophora|}}
{{taxon|order|subclass|{{taxlink|Neoloricata|subclass}}}}
{{taxon|suborder|order|{{taxlink|Neoloricata|order}}}}
- Chlamydiae
{{taxon|phylum|kingdom|Bacteria|i=1|now ''{{taxlink|Chlamydiota|phylum}}''}}
{{taxon|class|phylum|{{taxlink|Chlamydiota|phylum}}|i=1}}
- Chlamyphoridae
{{taxon|family|order|Cingulata|the [[cingulate]]s in genus ''[[Chlamyphorus]]''}}
{{taxon|family|order|Cingulata|all [[cingulate]]s except those in genus ''[[Dasypus]]''}}
- Chlamys
{{taxon|genus|family|Pectinidae|small [[scallop]]s; many species formerly included in ''Chlamys'' are now in other genera in Pectinidae}}
{{taxon|genus|family|Chrysomelidae|{{vern|warty leaf beetle|pl=s}}, now {{taxlink|Neochlamisus|genus}}}}
- Chloris
{{taxon|genus|family|Poaceae|[[windmill grass]]es}}
{{taxon|genus|family|Fringillidae|[[greenfinch]]es}}
- Chloroflexi
{{taxon|phylum|subkingdom|Posibacteria|i=1|now ''{{taxlink|Chloroflexota|phylum}}''}}
{{taxon|class|phylum|{{taxlink|Chloroflexota|phylum}}|now ''{{taxlink|Chloroflexia|class}}''|i=1}}
- Chlorophyceae
{{taxon|class|division|Chlorophyta}}
{{taxon|class|subphylum|Chlorophytina}}
- Chlorophyta
{{taxon|division|kingdom|Plantae}}
{{taxon|infrakingdom|subkingdom|Viridiplantae}}
{{taxon|phylum|infrakingdom|Chlorophyta}}
- Chondrilla
{{taxon|genus|family|Asteraceae|certain plants}}
{{taxon|genus|family|Chondrillidae|certain sea sponges}}
- Chordata
{{taxon|phylum|superphylum|Deuterostomia}}
{{taxon|phylum|infrakingdom|Deuterostomia}}
- Chromista
{{taxon|taxon|subkingdom|Biciliata|all [[algae]] whose [[chloroplast]]s contain [[chlorophyll]]s '''a''' and '''c'''}}
{{taxon|kingdom|superkingdom|Eukaryota|}}
- Chrysiogenetes
{{taxon|phylum|kingdom|Bacteria|[[bacteria]] that utilize [[arsenic]] compounds instead of [[oxygen]], now ''{{taxlink|Chrysiogenota|phylum}}''|i=1}}
{{taxon|class|phylum|{{taxlink|Chrysiogenota|phylum}}|i=1|now ''{{taxlink|Chrysiogenia|class}}''}}
- Ciliata
{{taxon|genus|family|Lotidae|certain [[rockling]]s}}
{{taxon|class|phylum|Alveolata|certain protozoa, [[ciliate]]s}}
- Cinclidium
{{taxon|genus|family|Muscicapidae|the {{vern|blue-fronted robin}} ({{taxlink|Cinclidium frontale|species}})}}
{{taxon|genus|family|Mniaceae|{{vern|cinclidium moss}}}}
- Cladocera
{{taxon|order|infraclass|Diplostraca}}
{{taxon|suborder|order|Diplostraca}}
- Claytonia
{{taxon|genus|family|{{taxlink|Montiaceae|family}}}}
{{taxon|genus|family|Portulacaceae}}
- Clivia
{{taxon|genus|family|Amaryllidaceae|the [[clivia]]s or [[kaffir lily|kaffir lilies]]}}
{{taxon|genus|family|Encyrtidae|a monotypic taxon, containing only {{taxlink|Clivia antoninae|species}}, a [[parasitoid]] [[chalcid wasp]] of China}}
- Clotho
{{taxon|genus|family|Oecobiidae|[[arachnids]], {{vern|wall spider|pl=s}}, with its species now in other genera in {{ll|mul|Oecobiidae}}}}
{{taxon|genus|family|Viperidae|[[viper]]s, with its species now in other genera in {{ll|mul|Viperidae}}}}
{{taxon|genus|family|Trochilidae|certain [[hummingbird]]s}}
- Clytemnestra
{{taxon|genus|family|{{taxlink|Peltidiidae|family}}}}
{{taxon|genus|family|{{taxlink|Clytemnestridae|family}}}}
{{taxon|genus|family|Cerambycidae|certain [[longhorn beetle]]s}}
- Cnidaria
{{taxon|phylum|kingdom|Metazoa}}
{{taxon|phylum|kingdom|Animalia}}
- Coccidia
{{taxon|subclass|class|{{taxlink|Conoidasida|class}}|various [[parasitic]] [[protozoa]]}}
{{taxon|subclass|class|{{taxlink|Coccidiomorphea|class}}|various [[parasitic]] [[chromist]]s}}
- Coccoidea
{{taxon|superfamily|order|Hemiptera|[[scale insect]]s, including [[mealy bug]]s}}
{{taxon|genus|family|Coccoideaceae|certain [[ascomycete]]s}}
- Coelodiazesis
{{taxon|genus|family|Culicidae|one species of [[mosquito]], {{taxlink|Coelodiazesis barberi|species}} (now {{taxlink|Anopheles barberi|species}})}}
{{taxon|subgenus|family|Culicidae|{{taxlink|Anopheles (Coelodiazesis)|subgenus}}, now included in subgenus {{taxlink|Anopheles (Anopheles)|subgenus}}}}
- Cola
{{taxon|genus|family|Malvaceae|[[kola nut]] trees}}
{{taxon|genus|family|Noctuidae|certain [[moth]]s}}
- Collinsia
{{taxon|genus|family|Plantaginaceae|about 20 accepted species of [[annual]] [[flowering plant]]s, called {{vern|blue eyed Mary|pl=s}} and {{vern|Chinese houses}}}}
{{taxon|genus|family|Linyphiidae|certain [[spider]]s}}
- Colocasia
{{taxon|genus|family|Araceae|herbaceous perennial plants with a large [[corm]] on or just below the ground surface and large to very large leaves, such as [[taro]]}}
{{taxon|genus|family|Noctuidae|certain [[moth]]s}}
- Cooperia
{{taxon|genus|family|Cooperiidae|certain [[nematode]]s}}
{{taxon|genus|family|Amaryllidaceae|certain plants}}
- Cordia
{{taxon|genus|family|Boraginaceae|certain flowering plants, including [[manjack]]s}}
{{taxon|genus|family|{{taxlink|Aphrophoridae|family}}|certain [[spittlebug]]s}}
- Corona
{{taxon|genus|family|{{taxlink|Orthalicidae|family}}|certain [[pulmonate]] [[land snail]]s [[endemic]] to [[South America]]}}
{{taxon|genus|family|Liliaceae|now included in ''[[Fritillaria]]''}}
- Coxiella
{{taxon|genus|family|{{taxlink|Coxiellaceae|family}}|i=1|a [[bacteria]] species that causes [[Q fever]]}}
{{taxon|genus|family|{{taxlink|Tomichiidae|family}}|certain [[snail]]s from [[saline]] [[lake]]s in Australia}}
- Craniata
{{taxon|clade|phylum|Chordata|animals with [[skull]]-like elements}}
{{taxon|class|phylum|Brachiopoda}}
- Crenarchaeota
{{taxon|phylum|kingdom|Archaea|many [[bacteria]]-[[like]] organisms, some of which are [[extremophile]]s|i=1}}
{{taxon|class|phylum|Crenarchaeota|''{{ll|mul|Thermoprotei}}''|i=1}}
- Crepis
{{taxon|genus|family|Asteraceae|[[hawksbeard]]}}
{{taxon|genus|family|{{taxlink|Calloporidae|family}}|little-known [[bryozoan]]s, of recently revised placement}}
- Crinoidea
{{taxon|class|subphylum|Pelmatozoa}}
{{taxon|class|subphylum|Crinozoa}}
- Crocodylomorpha
{{taxon|superorder|division|Archosauria}}
{{taxon|subclass|class|Reptilia}}
- Cryptista
{{taxon|phylum|taxon|Chromista}}
{{taxon|phylum|subkingdom|Hacrobia}}
- Cryptococcus
{{taxon|genus|family|Tremellaceae}}
{{taxon|genus|family|{{taxlink|Cryptococcaceae|family}}}}
{{taxon|genus|family|Eriococcidae|certain [[scale insect]]s, {{vern|soft scale|pl=s}}, some of which are [[pest]]s in [[agriculture]]}}
- Cryptomeria
{{taxon|genus|family|Cupressaceae|one species, the {{l|en|Japanese cedar}} ({{taxlink|Cryptomeria japonica|species}}), the seeds of which are in the scales of the cones}}
{{taxon|genus|family|Noctuidae|a genus of {{l|en|moth|moths}}}}
- Cryptomonada
{{taxon|subphylum|phylum|Cryptista}}
{{taxon|superclass|subphylum|Rollomonadia}}
- Cryptophyceae
{{taxon|class|subphylum|Cryptomonada}}
{{taxon|class|subphylum|Rollomonadia}}
- Cryptosporidiidae
{{taxon|family|order|Eucoccidiorida}}
{{taxon|family|order|Eimerida}}
- Ctenopharyngodon idella
{{taxon|species|family|Cyprinidae}}
{{taxon|species|family|{{taxlink|Xenocypridinae|family}}}}
- Ctenophora
{{taxon|phylum|superphylum|Radiata}}
{{taxon|phylum|kingdom|Animalia}}
- Culex
{{taxon|genus|family|Culicidae|certain [[mosquito]]es, including several that transmit important diseases}}
{{taxon|subgenus|family|Culicidae|certain [[mosquito]]es (''[[Culex (Culex)]]'')}}
- Cupressaceae
{{taxon|family|order|Pinales}}
{{taxon|family|order|Cupressales}}
- Cutleria
{{taxon|genus|family|Cutleriaceae|certain [[brown alga]]e}}
{{taxon|genus|family|{{taxlink|Sphenacodontidae|family|†Sphenacodontidae}}|certain extnct [[synapsid]]s}}
- Cyanea
{{taxon|genus|family|Cyaneidae|various [[jellyfish]] found in the northern waters of the Atlantic and Pacific oceans}}
{{taxon|genus|family|Campanulaceae|several nearly branchless trees native to [[Hawaii]]}}
- Cyanobacteria
{{taxon|phylum|kingdom|Bacteria|(formerly within [[subkingdom]] ''[[Eubacteria]]'') [[blue-green alga]]e|i=1}}
{{taxon|class|phylum|Cyanobacteria|i=1}}
- Cycadophyta
{{taxon|phylum|kingdom|Plantae|the [[cycad]]s etc}}
{{taxon|division|phylum|Tracheophyta|the [[cycad]]s etc}}
- Cyclophyllidea
{{taxon|order|subclass|Neodermata}}
{{taxon|order|subclass|Eucestoda}}
- Cyclospora
{{taxon|genus|family|Eimeriidae|described by Schneider, certain [[chromist]]s including one (''[[Cyclospora cayetanensis]]'') causing [[diarrhea]] in humans}}
{{taxon|genus|family|Ceramiaceae|described by Agardh, certain [[red alga]]e, now in {{taxlink|Carpoblepharis|genus}}}}
- Cyclostomata
{{taxon|class|subphylum|Vertebrata|the living [[jawless]] [[fish]]es: [[lamprey]]s and [[hagfish]]es; the [[cyclostome]]s}}
{{taxon|order|phylum|Bryozoa|the {{ll|mul|Cyclostomatida}}}}
- Cynodon
{{taxon|genus|family|Poaceae|several species of {{l|en|grass}}}}
{{taxon|genus|family|{{taxlink|Cynodontidae|family}}|{{vern|dogtooth characin|pl=s}}}}
- Cyperoideae
{{taxon|subfamily|family|Cyperaceae|typical [[sedge]]s}}
{{taxon|section|family|Cyperaceae|{{taxlink|Carex sect. Cyperoideae|section}}, now including species formerly in section ''Ovales''}}
- Cystophora
{{taxon|genus|family|Phocidae|[[hooded seal]]}}
{{taxon|genus|family|Sargassaceae|certain [[brown alga]]e}}
- Dahlia
{{taxon|genus|family|Asteraceae|[[dahlia]]s, dahlia flowers}}
{{taxon|genus|family|Noctuidae|various [[moth]]s}}
- Danaus
{{taxon|genus|family|Nymphalidae|called [[tiger]]s, [[milkweed]]s, [[monarch]]s, [[wanderer]]s, and [[queen]]s}}
{{taxon|subgenus|family|Nymphalidae|{{taxlink|Danaus (Danaus)|subgenus}}, that includes ''{{l|mul|Danaus plexippus}}''}}
- Darlingtonia
{{taxon|genus|family|Sarraceniaceae|[[California pitcher plant]], [[cobra lily]]}}
{{taxon|genus|family|Colubridae|certain snakes}}
- Decodon
{{taxon|genus|family|Labridae|certain [[wrasse]]s}}
{{taxon|genus|family|Lythraceae|the [[waterwillow]] or {{vern|swamp loosestrife}}}}
- Decumaria
{{taxon|genus|family|Hydrangeaceae|the }}
{{taxon|section|family|Hydrangeaceae|{{taxlink|Hydrangea sect. Decumaria|section}}}}
- Deferribacteres
{{taxon|phylum|kingdom|Bacteria|i=1|now {{taxlink|Deferribacterota|phylum}}}}
{{taxon|class|phylum|{{taxlink|Deferribacterota|phylum}}|i=1}}
- Deidamia
{{taxon|genus|family|Sphingidae|{{taxlink|Deidamia inscriptum|species}}}}
{{taxon|genus|family|Passifloraceae|}}
- Dendroceratida
{{taxon|order|subclass|Ceractinomorpha|}}
{{taxon|order|class|Demospongiae}}
- Dentaria
{{taxon|genus|family|Brassicaceae}}
{{taxon|subgenus|family|Brassicaceae|{{taxlink|Cardamine subg. Dentaria|subgenus}}}}
- Desmidiales
{{taxon|order|class|Charophyceae}}
{{taxon|order|class|Conjugatophyceae}}
- Deuterostomia
{{taxon|infrakingdom|subkingdom|Bilateria}}
{{taxon|superphylum|subkingdom|Eumetazoa}}
- Dianthus compactus
{{taxon|species|family|Caryophyllaceae|''[[Dianthus barbatus]]''; [[sweet william]]}}
{{taxon|subspecies|family|Caryophyllaceae|{{taxlink|Dianthus barbatus subsp. compactus|subspecies}}}}
- Diascia
{{taxon|genus|family|Scrophulariaceae|[[twinspur]]s}}
{{taxon|genus|family|Noctuidae|certain moths}}
- Dicentra
{{taxon|genus|family|Papaveraceae|}}
{{taxon|genus|family|Fumariaceae|about a dozen species of perennial herbs with [[glaucous]] [[dissected]] leaves and a heart-shaped or two-spurred [[corolla]], including ''[[Dicentra spectabilis]]'', now ''[[Lamprocapnos spectabilis]]''}}
- Dicondylia
{{taxon|clade|class|Insecta|all living insects, excluding the primitive {{ll|mul|Monocondylia}}}}
{{taxon|subclass|class|Insecta|the single order {{ll|mul|Zygentoma}}}}
- Dictyoptera
{{taxon|cohort|supercohort|Polyneoptera}}
{{taxon|genus|family|Lycidae|the [[net-winged beetle]]s}}
- Dicyemida
{{taxon|phylum|group|Mesozoa}}
{{taxon|order|phylum|Rhombozoa}}
- Digitaria
{{taxon|genus|family|Poaceae|[[crabgrass]]es, [[fonio]], and others}}
{{taxon|genus|family|Astartidae|a single species of [[clam]]s}}
- Dikarya
{{taxon|subkingdom|kingdom|Fungi}}
{{taxon|clade|clade|Opisthokonta}}
- Dilepis
{{taxon|genus|family|Dilepididae|certain [[tapeworms]]}}
{{taxon|genus|family|Asteraceae|{{synonym of|mul|Flaveria}}, flowering plants called [[yellowtop]]s}}
- Dinoflagellata
{{taxon|superclass|phylum|Miozoa}}
{{taxon|parvphylum|phylum|Miozoa}}
- Dionaea
{{taxon|genus|family|Droseraceae|certain [[sundew]] plants}}
{{taxon|genus|family|Tachinidae|{{vern|tachina fly|tachina flies}}}}
- Diplostraca
{{taxon|infraclass|class|Branchiopoda}}
{{taxon|order|class|Branchiopoda}}
- Diplura
{{taxon|order|superorder|Diplurata}}
{{taxon|class|subphylum|Hexapoda}}
{{taxon|genus|family|{{taxlink|Dipluridae|family}}|a South American [[spider]]}}
- Dipnoi
{{taxon|subclass|class|Sarcopterygii}}
{{taxon|infraclass|subclass|Sarcopterygii}}
{{taxon|class|superclass|Sarcopterygii}}
- Discina
{{taxon|genus|family|Discinaceae|certain ascomycete fungi}}
{{taxon|genus|family|{{taxlink|Discinidae|family}}|extinct brachiopods}}
- Discophora
{{taxon|genus|family|Nymphalidae|[[duffer]] butterflies of Asia}}
{{taxon|genus|family|{{taxlink|Stemonuraceae|family}}|trees of the [[New World]] tropics}}
{{taxon|class|phylum|Cnidaria|a taxon broadly equivalent to modern [[Scyphozoa]]}}
{{taxon|subclass|class|Scyphozoa|a [[paraphyletic]] taxon of varying composition, but usually [[Semaeostomeae]] and [[Rhizostomae]]}}
- Discula
{{taxon|genus|family|{{taxlink|Hygromiidae|family}}|the {{vern|hairy snail|pl=s}} and their allies}}
{{taxon|genus|family|Gnomoniaceae|certain fungi that are plant [[pathogen]]s}}
- Dolichos
{{taxon|genus|family|Fabaceae|certain plants of Africa and Asia, [[hyacinth bean]]s}}
{{taxon|genus|family|Carabidae|now subgenus {{taxlink|Calathus (Dolichus)|subgenus}}, certain [[ground beetle]]s}}
- Donax
{{taxon|genus|family|Donacidae|marine clams, the [[bean clam]]s or [[coquina]]}}
{{taxon|genus|family|Marantaceae|a single species of plants from [[Southeast Asia]] and [[Oceania]]}}
- Dracaena
{{taxon|genus|family|Asparagaceae|[[dragon tree]]s, of the Canary Islands}}
{{taxon|genus|family|Teiidae|[[caiman lizard]]s, of the tropical Americas}}
- Dracunculidae
{{taxon|family|order|Spirurida}}
{{taxon|family|order|Rhabditida}}
- Dracunculoidea
{{taxon|superfamily|order|Spirurida}}
{{taxon|superfamily|order|Rhabditida}}
- Dracunculus
{{taxon|genus|family|Dracunculidae|greatly [[elongated]] [[nematode]] worms including the {{vern|Guinea worm}}}}
{{taxon|genus|family|Araceae|[[tuberous]] [[aroid]] [[perennial]]s sometimes grown for [[ornamental]] purposes}}
- Drosophila
{{taxon|genus|family|Drosophilidae|[[fruit fly|fruit flies]] or [[drosophila]]s}}
{{taxon|subgenus|family|Drosophilidae|{{taxlink|Drosophila (Drosophila)|subgenus}}}}
- Dryas
{{taxon|genus|family|Rosaceae|many [[alpine]] plants}}
{{taxon|genus|family|Nymphalidae|certain [[butterfly|butterflies]]}}
- Dryopteris
{{taxon|genus|family|Dryopteridaceae|[[wood fern]]s, [[buckler|buckler fern]]s, or [[shield fern]]s, and [[male fern]]s}}
{{taxon|genus|family|{{taxlink|Drepanidae|family}}|certain [[moth]]s, now considered a junior synonym of ''[[Oreta]]''}}
- Dulcamara
{{taxon|genus|family|Solanaceae|synonymized with ''[[Solanum]]''}}
{{taxon|section|family|Solanaceae|{{taxlink|Solanum sect. Dulcamara|section}}}}
- Ebenus
{{taxon|genus|family|Fabaceae}}
{{taxon|genus|family|Ebenaceae|[[ebony]], ''[[Diospyros]]''}}
- Ecdysozoa
{{taxon|clade|clade|Protostomia}}
{{taxon|superphylum|infrakingdom|Protostomia}}
- Echinacea
{{taxon|superorder|class|Echinoidea|[[sea urchin]]s with solid [[spine]]s and [[gill]]s}}
{{taxon|genus|family|Asteraceae|the [[coneflower]]s}}
- Echinops
{{taxon|genus|family|Asteraceae|[[globe thistle]]s}}
{{taxon|genus|family|Tenrecidae|{{vern|lesser hedgehog tenrec|pl=s}} ({{taxlink|Echinops telfairi|species}}), of Madagascar}}
- Edwardsia
{{taxon|genus|family|Edwardsiidae|certain [[sea anemone]]s}}
{{taxon|genus|family|Fabaceae|now {{taxlink|Sophora sect. Edwardsia|section}}}}
- Edwardsiella
{{taxon|genus|family|{{taxlink|Hafniaceae|family}}|i=1|certain [[gram-negative]], [[fermentative]] [[bacterium|bacteria]]}}
{{taxon|genus|family|Edwardsiidae|certain [[sea anemone]]s}}
- Elasmobranchii
{{taxon|subclass|class|Chondrichthyes}}
{{taxon|class|superclass|Chondrichthyes}}
- Elusimicrobia
{{taxon|phylum|subkingdom|Negibacteria|i=1}}
{{taxon|class|phylum|Elusimicrobia|i=1}}
- Embioptera
{{taxon|order|subdivision|Pterygota}}
{{taxon|order|class|Polyneoptera}}
- Embryophyta
{{taxon|subkingdom|subdivision|Streptophytina}}
{{taxon|superphylum|infrakingdom|Streptophyta}}
- Ensifera
{{taxon|genus|family|Trochilidae|the {{vern|sword-billed hummingbird}}}}
{{taxon|suborder|order|Orthoptera|the [[cricket]]s, [[katydid]]s and [[weta]]}}
- Entomophaga
{{taxon|genus|family|Tachinidae|certain [[fly|flies]]}}
{{taxon|genus|family|Entomophthoraceae|certain [[pathogenic]] [[fungus|fungi]] of insects}}
- Eozoa
{{taxon|superphylum|clade|Excavata}}
{{taxon|subkingdom|kingdom|Protozoa}}
- Ephemera
{{taxon|genus|family|{{taxlink|Ephemeridae|family}}|certain [[mayfly|mayflies]]}}
{{taxon|genus|order|{{taxlink|Naviculales|order}}|certain [[diatom]]s}}
- Equus asinus
{{taxon|species|family|Equidae|[[donkey]]s or [[ass]]es, often domesticated}}
{{taxon|species|family|Equidae|{{vern|African wild ass|pl=es}} and the domesticated asses believed derived from them or from a close extinct relative}}
- Eremophila
{{taxon|genus|family|Alaudidae|[[horned lark]]s}}
{{taxon|genus|family|Scrophulariaceae|Australian desert shrubs and trees, many called {{vern|poverty bush|pl=es}} and [[emu bush]]es}}
- Erica
{{taxon|genus|family|Ericaceae|[[heath]]s and [[heather]]s}}
{{taxon|genus|family|Salticidae|certain [[jumping spider]]s}}
- Eruca
{{taxon|genus|family|Brassicaceae|[[rocket]] and closely related plants}}
{{taxon|genus|family|Saturniidae|certain [[saturniid]] [[moth]]s}}
- Eucharis
{{taxon|genus|family|Amaryllidaceae|several [[bulbous]] [[plant]]s from [[Central America|Central]] and [[South America]]}}
{{taxon|genus|family|Eucharitidae|certain parasitoid [[chalcid wasp]]s}}
- Euglenozoa
{{taxon|infrakingdom|subkingdom|Eozoa|}}
{{taxon|phylum|infrakingdom|Euglenozoa|}}
- Eulalia
{{taxon|genus|family|{{taxlink|Phyllodocidae|family}}|certain [[polychaete]] [[worm]]s}}
{{taxon|genus|family|Stratiomyidae|a synonym for the genus ''{{ll|mul|Odontomyia}}'' of flies}}
{{taxon|genus|family|Poaceae|tropical [[perennial]] [[grass]]es}}
- Eulipotyphla
{{taxon|order|class|Mammalia}}
{{taxon|clade|clade|Laurasiatheria}}
- Eupatorium
{{taxon|genus|family|Asteraceae|[[boneset]]s, [[thoroughwort]]s, and [[snakeroot]]s}}
{{taxon|genus|family|Asteraceae|all of ''Eupatorium sensu stricto'' and more than a dozen of what are now considered separate genera}}
- Eupelycosauria
{{taxon|suborder|superclass|Tetrapoda|[[pelycosaur]]s}}
{{taxon|clade|superclass|Tetrapoda|[[synapsid]]s, including most [[pelycosaur]]s, as well as all [[therapsid]]s and [[mammals]]}}
- Euphractinae
{{taxon|subfamily|family|Dasypodidae}}
{{taxon|subfamily|family|Chlamyphoridae}}
- Eupulmonata
{{taxon|suborder|order|Pulmonata|the [[slug]]s}}
{{taxon|superorder|class|Gastropoda}}
- Euryale
{{taxon|genus|family|Nymphaeaceae|[[water lily|water lilies]] growing in [[India]] and [[China]]}}
{{taxon|genus|family|{{taxlink|Euryalidae|family}}|[[ophiuran]]s with much-branched arms}}
- Eurybia
{{taxon|genus|family|Asteraceae|formerly included in genus ''[[Aster]]''}}
{{taxon|genus|family|Riodinidae|certain [[New World]] [[metalmark]] [[butterfly|butterflies]]}}
- Eurypygiformes
{{taxon|order|class|Aves}}
{{taxon|order|class|Reptilia}}
- Euthyneura
{{taxon|clade|class|Gastropoda|certain [[snail]]s and [[slug]]s}}
{{taxon|genus|family|{{taxlink|Hybotidae|family}}| [[dance fly|dance flies]]}}
- Excavata
{{taxon|clade|supergroup|Bikonta}}
{{taxon|infrakingdom|subkingdom|Eozoa}}
- Falconiformes
{{taxon|order|parvclass|Neognathae}}
{{taxon|order|superorder|Neoaves|only the family {{ll|mul|Falconidae}}}}
- Farancia
{{taxon|genus|family|{{taxlink|Dipsadidae|family}}}}
{{taxon|genus|family|Colubridae}}
- Fenestella
{{taxon|genus|family|Fenestellidae|extinct [[bryozoan]]s forming fan-shaped colonies with a netted appearance}}
{{taxon|genus|family|{{taxlink|Fenestellaceae|family}}|certain [[fungus|fungi]]}}
{{taxon|genus|family|Anomiidae|certain [[mollusc]]s, now ''{{ll|mul|Anomia}}''}}
- Filarioidea
{{taxon|superfamily|order|Spirurida}}
{{taxon|superfamily|order|Rhabditida}}
- Finschia
{{taxon|genus|family|Proteaceae|trees native to [[Papua]] and [[Oceania]]}}
{{taxon|genus|family|Acanthizidae|}}
{{taxon|genus|family|{{taxlink|Mohouidae|family}}|now ''[[Mohoua]]''}}
- Fistularia
{{taxon|genus|family|Fistulariidae|[[cornetfish]]es or [[flutemouth]]s, sole genus in its family}}
{{taxon|genus|family|Ulvaceae|certain [[alga]]e now in genus ''[[Ulva]]''}}
- Florissantia
{{taxon|genus|family|Malvaceae|certain extinct flowering plants}}
{{taxon|genus|family|{{taxlink|Dictyopharidae|family}}|certain extinct [[planthopper]]s}}
- Foraminifera
{{taxon|subphylum|phylum|Retaria}}
{{taxon|infraphylum|phylum|Retaria}}
- Frankia
{{taxon|genus|family|{{taxlink|Frankiaceae|family}}|i=1|[[nitrogen-fixing]], [[filamentous]] bacteria that live in [[symbiosis]] with [[actinorhizal]] plants}}
{{taxon|genus|family|Gnomoniaceae|now {{taxlink|Greeneria|genus}} (certain [[ascomycete]] fungi)}}
- Fridericia
{{taxon|genus|family|Enchytraeidae|resembling small earthworms, including [[potworm]]s and [[ice worm]]s}}
{{taxon|genus|family|Bignoniaceae|conspicuously flowering [[New World]] tropical trees}}
- Fritillaria
{{taxon|genus|family|Liliaceae|[[fritillary]] flowering plants}}
{{taxon|genus|family|{{taxlink|Fritillariidae|family}}|many small free-swimming [[tunicate]]s}}
- Furcifer
{{taxon|genus|family|Chamaeleonidae}}
{{taxon|genus|family|Cervidae|South American deer with [[furcate]] antlers, now {{taxlink|Hippocamelus|genus}} }}
- Fusobacteria
{{taxon|phylum|kingdom|Bacteria|i=1}}
{{taxon|class|phylum|Fusobacteria|i=1|now {{taxlink|Fusobacteriia|class}}}}
- Gastrotricha
{{taxon|phylum|superphylum|Protostomia}}
{{taxon|phylum|superphylum|Spiralia}}
- Gekkota
{{taxon|order|class|Reptilia}}
{{taxon|infraorder|suborder|Sauria|}}
- Geotria
{{taxon|genus|family|Geotridae}}
{{taxon|genus|family|Petromyzontidae}}
- Geotria australis
{{taxon|species|family|{{taxlink|Geotridae|family}}}}
{{taxon|species|family|Petromyzontidae}}
- Gesneria
{{taxon|genus|family|Gesneriaceae|certain flowering plants}}
{{taxon|genus|family|Crambidae|certain moths}}
- Giraffa camelopardalis
{{taxon|species|family|Giraffidae|all extant [[giraffe]]s}}
{{taxon|species|family|Giraffidae|the {{vern|northern giraffe}}}}
- Glaucidium
{{taxon|genus|family|Strigidae|[[pygmy owl]]s}}
{{taxon|genus|family|Ranunculaceae|{{vern|Japanese wood poppy}}}}
- Glaucium
{{taxon|genus|family|Papaveraceae|[[horned poppy]]}}
{{taxon|genus|family|Cerambycidae|}}
- Glaux
{{taxon|genus|family|Primulaceae|[[milkwort]]s; now a single species of [[flowering plant]], {{vern|sea milkwort}}, now sometimes {{taxlink|Lysimachia maritima|species}}}}
{{taxon|genus|order|Strigiformes|certain [[owl]]s}}
- Glires
{{taxon|clade|superorder|Euarchontoglires|[[rodent]]s, [[rabbit]]s, [[hare]]s, and [[pika]]s}}
{{taxon|order|class|Mammalia|[[rodent]]s and [[rabbit]]-like animals}}
{{taxon|order|class|Mammalia|corresponding to {{ll|mul|Rodentia}}, plus ''{{ll|mul|Noctilio}}''}}
- Glomeromycota
{{taxon|division|kingdom|Fungi}}
{{taxon|phylum|subkingdom|Eomycota}}
- Glyphis
{{taxon|genus|family|Carcharhinidae|[[river shark]]s}}
{{taxon|genus|family|{{taxlink|Graphidaceae|family}}|certain [[lichen]]s}}
- Gmelina
{{taxon|genus|family|Lamiaceae|plants, principally of southeast Asia, [[Micronesia]], and Australia}}
{{taxon|genus|family|Gammaridae|certain shrimp-like [[crustacean]]s}}
- Gnathostomata
{{taxon|infraphylum|subphylum|Vertebrata|those [[vertebrate]]s that have [[jaw]]s}}
{{taxon|superorder|class|Echinoidea|some [[sea urchin]]s, including the [[sand dollar]]s}}
- Gnathostomatidae
{{taxon|family|order|Spirurida}}
{{taxon|family|order|Rhabditida}}
- Gordonia
{{taxon|genus|family|Theaceae|certain flowering plants, principally of southeastern Asia}}
{{taxon|genus|family|{{taxlink|Gordoniaceae|family}}|certain bacteria}}
{{taxon|genus|clade|{{taxlink|Dicynodontoidea|clade|†Dicynodontoidea}}|extinct [[therapsid]]s from the [[Late Permian]] of Scotland}}
- Gouldia
{{taxon|genus|family|Veneridae|a [[bivalve]]}}
{{taxon|genus|family|Rubiaceae|now subsumed into genus {{taxlink|Kadua|genus}}}}
- Grammitis
{{taxon|genus|family|Polypodiaceae|a few hundred species now many dispersed among numerous genera in [[Polypodiaceae]] and some in [[Pteridaceae]]}}
{{taxon|genus|family|Polypodiaceae|{{vern|dwarf polypody}} (about 25 species)}}
- Graphis
{{taxon|genus|family|{{taxlink|Graphidaceae|family}}|{{vern|script lichen|pl=s}}}}
{{taxon|genus|class|Gastropoda|certain [[sea snail]]s}}
- Graphium
{{taxon|genus|family|Papilionidae|many species of [[butterfly]], many known as [[swordtail]]s, [[zebra]]s, [[bluebottle]]s, [[jay]]s, [[triangle]]s, etc.}}
{{taxon|genus|family|{{taxlink|Microascaceae|family}}|certain [[fungus|fungi]] that are plant [[pathogen]]s}}
- Gymnospermae
{{taxon|clade|clade|spermatophytes}}
{{taxon|superclass|subphylum|Spermatophytina}}
- Haemosporida
{{taxon|order|class|Aconoidasida}}
{{taxon|order|class|{{taxlink|Coccoidiomorphea|class}}}}
- Haplomi
{{taxon|order|class|Teleostei}}
{{taxon|suborder|class|Teleostei}}
- Harrisia
{{taxon|genus|family|Tachinidae|certain flies}}
{{taxon|genus|family|Cactaceae|[[applecactus]], [[moonlight cactus]]}}
- Haya
{{taxon|genus|family|{{taxlink|Thescelosauridae|family|†Thescelosauridae}}|an extinct bird-like [[dinosaur]] from the Late [[Cretaceous]] of [[Mongolia]]}}
{{taxon|genus|family|Caryophyllaceae}}
- Helicina
{{taxon|suborder|order|Stylommatophora|}}
{{taxon|genus|family|Helicinidae}}
- Heliozoa
{{taxon|phylum|subkingdom|Biciliata}}
{{taxon|subphylum|phylum|{{taxlink|Haptista|phylum}}}}
- Hepatica
{{taxon|section|family|Ranunculaceae|{{taxlink|Anemone sect. Hepatica|section}}}}
{{taxon|genus|family|Ranunculaceae}}
{{taxon|genus|family|Erebidae|certain [[moth]]s}}
- Heterobranchia
{{taxon|superorder|subclass|Orthogastropoda}}
{{taxon|subclass|class|Gastropoda}}
- Heterophyidae
{{taxon|family|order|Plagiorchiida}}
{{taxon|family|order|Opisthorchiida}}
- Holostei
{{taxon|infraclass|subclass|Neopterygii|}}
{{taxon|class|superclass|Actinopterygii}}
- Hygrophila
{{taxon|genus|family|Acanthaceae|[[swampweed]]s}}
{{taxon|superorder|class|Gastropoda|}}
- Hymenolepis
{{taxon|genus|family|Hymenolepididae|[[tapeworm]]s responsible for [[hymenolepiasis]]}}
{{taxon|genus|family|Asteraceae|certain [[asterid]] plants}}
- Hypoderma
{{taxon|genus|family|Oestridae|[[warble fly|warble flies]]}}
{{taxon|genus|family|{{taxlink|Rhytismataceae|family}}|a [[fungus]]}}
- Hypotrichia
{{taxon|genus|family|Scarabaeidae|certain beetles}}
{{taxon|subclass|class|{{taxlink|Spirotrichea|class}}}}
- Hyssopus
{{taxon|genus|family|Lamiaceae|[[aromatic]] plants, including [[hyssop]]}}
{{taxon|genus|family|Eulophidae|parasitic [[hymenopteran]] insects}}
- Hystrix
{{taxon|genus|family|Hystricidae|certain [[Old World porcupine]]s}}
{{taxon|genus|family|Poaceae|species now transferred to genera ''[[Elymus]]'' and ''[[Leymus]]''}}
- Iguanidae
{{taxon|family|order|Iguania|also known as {{taxlink|Iguaninae|subfamily}} in {{ll|mul|Iguanidae}} ({{ll|mul|sensu lato}})}}
{{taxon|family|order|Iguania|including all members of {{ll|mul|Iguania}} except those of families {{ll|mul|Agamidae}} and {{ll|mul|Chamaeleonidae}}}}
- Inga
{{taxon|genus|family|Fabaceae|small [[neotropical]], tough-leaved, nitrogen-fixing trees and [[shrub]]s, many used as [[ornamental]]s}}
{{taxon|genus|family|Oecophoridae|certain of the {{vern|concealer moth|pl=s}}}}
- Io
{{taxon|genus|family|{{taxlink|Pleuroceridae|family}}|only one species {{taxlink|Io fluvialis|species}} ({{vern|spiny river snail}})}}
{{taxon|genus|family|Saturniidae|now genus {{taxlink|Adetomeris|genus}}, of [[moth]]s}}
{{taxon|genus|family|Asteraceae|only one species {{taxlink|Io ambondrombeensis|species}}, native to Madagascar}}
- Iris
{{taxon|genus|family|Iridaceae|[[iris]]es}}
{{taxon|genus|family|{{taxlink|Tarachodidae|family}}|certain of the [[mantis]]es}}
- Ischnochitonina
{{taxon|suborder|order|Loricata}}
{{taxon|suborder|order|Chitonida}}
{{taxon|order|class|Polyplacophora|{{ll|mul|Chitonida}}}}
- Ismene
{{taxon|genus|family|Amaryllidaceae|[[Peruvian daffodil]]s, native to [[Peru]] and [[Ecuador]] but widely cultivated elsewhere for their [[flower]]s}}
{{taxon|genus|family|Crambidae|a single species of [[moth]], endemic to [[Egypt]]}}
- Isoptera
{{taxon|clade|order|Blattodea|}}
{{taxon|epifamily|order|Blattodea}}
- Jacksonia
{{taxon|genus|family|Fabaceae|various plants}}
{{taxon|genus|family|Aphididae|various true bugs}}
{{taxon|genus|family|Lycaenidae|various butterflies, now genus {{taxlink|Cesa|genus}}}}
- Jubula
{{taxon|genus|family|Jubulaceae|a group of [[leafy liverwort]]s}}
{{taxon|genus|family|Strigidae|{{vern|maned owl}}, of western tropical Africa}}
- Jungermanniopsida
{{taxon|class|division|Marchantiophyta}}
{{taxon|class|phylum|Marchantiophyta}}
- Kali
{{taxon|genus|family|Chiasmodontidae|certain {{vern|snaketooth fish|pl=es}}, deep sea fish of fearsome appearance}}
{{taxon|genus|family|Amaranthaceae|certain prickly [[tumbleweed]]s; previously and again now usually included in genus ''[[Salsola]]''}}
- Kerria
{{taxon|genus|family|Kerriidae|certain scale insects}}
{{taxon|genus|family|Rosaceae|certain flowering plants}}
- Knightia
{{taxon|genus|family|Clupeidae|bony fish that lived in the freshwater lakes and rivers of North America and Asia during the Eocene epoch}}
{{taxon|genus|family|Proteaceae|a genus of [[extant]] woody plants [[endemic]] to New Zealand}}
- Kniphofia
{{taxon|genus|family|Xanthorrhoeaceae}}
{{taxon|genus|family|Asphodelaceae}}
- Lactarius
{{taxon|genus|family|Russulaceae|[[milk-cap]] mushrooms.}}
{{taxon|genus|family|{{taxlink|Lactariidae|family}}|[[false trevally|false travallies]] (fish)}}
- Laelia
{{taxon|genus|family|Orchidaceae|[[laelia]]s}}
{{taxon|genus|family|Brassicaceae|{{synonym of|mul|{{taxlink|Bunias|genus}}}}}}
- Lagurus
{{taxon|genus|family|Cricetidae|[[steppe lemming]]}}
{{taxon|genus|family|Poaceae|certain [[grass]]es}}
- Lansium parasiticum
{{taxon|species|family|Meliaceae|{{synonym of|mul|''[[Lansium domesticum]]''}}; [[langsat]], [[lanzones]], or [[longkong]], native to southeast Asia, grown more widely for its fruit}}
{{taxon|species|family|Meliaceae|{{synonym of|mul|{{taxlink|Dysoxylum parasiticum|species}}}}}}
- Lasiurus
{{taxon|genus|family|Vespertilionidae|{{vern|hairy-tailed bat|pl=s}}, [[New World]] tree-dwellers}}
{{taxon|genus|family|Poaceae|}}
- Lawsonia
{{taxon|genus|family|Lythraceae|[[henna]] plant}}
{{taxon|genus|family|{{taxlink|Desulfovibrionaceae|family}}|i=1|certain [[bacteria]]}}
{{taxon|genus|family|{{taxlink|Anthribidae|family}}|certain [[fungus weevil]]s}}
- Ledum
{{taxon|genus|family|Ericaceae}}
{{taxon|subsection|family|Ericaceae|{{taxlink|Rhododendron subsect. Ledum|subsection}}}}
- Leiothrix
{{taxon|genus|family|Leiothrichidae|certain [[babbler]]s}}
{{taxon|genus|family|{{taxlink|Eriocaulaceae|family}}|plants of tropical South America}}
- Leitneria
{{taxon|genus|family|Simaroubaceae|[[corkwood]] ({{taxlink|Leitneria floridiana|species}})}}
{{taxon|genus|family|{{taxlink|Halolaelapidae|family}}|certain [[mite]]s}}
- Leptonema
{{taxon|genus|family|{{taxlink|Hydropsychidae|family}}|certain [[caddis fly|caddis flies]]}}
{{taxon|genus|family|Phyllanthaceae|tropical [[flowering plant]]s of Madagascar}}
{{taxon|genus|family|Leptospiraceae|a [[spirochete]] [[bacterium]]}}
- Leptosomus
{{taxon|genus|family|{{taxlink|Leptosomatidae|family}}|the [[cuckoo roller]], sole member of its family, sometimes in its order}}
{{taxon|genus|order|Commelinales|now ''[[Pontederia]]''}}
- Lestoidea
{{taxon|superfamily|order|Odonata|some of the [[damselfly|damselflies]]}}
{{taxon|genus|family|{{taxlink|Lestoideidae|family}}|certain [[damselfly|damselflies]] of the rainforests of [[Queensland]], [[Australia]]}}
- Liparis
{{taxon|genus|family|Liparidae|typical [[snailfish]]es}}
{{taxon|genus|family|Orchidaceae|{{vern|widelip orchid|pl=s}}}}
- Lobosea
{{taxon|class|subphylum|Protamoebae}}
{{taxon|class|subphylum|Lobosa|[[Tubulinea]]}}
- Lobularia
{{taxon|genus|family|Brassicaceae}}
{{taxon|genus|family|Alcyoniidae|leathery [[soft coral]]s now in other genera}}
- Loricata
{{taxon|infraorder|order|Decapoda|now families {{taxlink|Galatheidae|family}}, {{taxlink|Munididae|family}}, [[Scyllaridae]], [[Palinuridae]]}}
{{taxon|class|phylum|Mollusca|[[Polyplacophora]], [[chiton]]s}}
{{taxon|clade|class|Reptilia|[[crocodylian]]s and their extinct close relatives}}
- Lucilia
{{taxon|genus|family|Calliphoridae|[[blow fly|blow flies]], including [[green bottle fly|green bottle flies]]}}
{{taxon|genus|family|Asteraceae}}
- Ludia
{{taxon|genus|family|Salicaceae}}
{{taxon|genus|family|Saturniidae}}
- Ludwigia
{{taxon|genus|family|Onagraceae|[[primrose-willow]], [[water-purslane]], or [[water-primrose]]}}
{{taxon|genus|family|{{taxlink|Graphoceratidae|family|†Graphoceratidae}}|certain extinct [[ammonite]]s}}
{{taxon|genus|family|Cerambycidae|certain [[beetle]]s}}
- Lunularia
{{taxon|genus|family|Lunulariaceae|a group of [[liverwort]]s}}
{{taxon|genus|family|{{taxlink|Lunulariidae|family}}|certain [[bryozoan]]s}}
- Lutreola
{{taxon|genus|family|Mustelidae|now included in genus ''[[Mustela]]''}}
{{taxon|subgenus|family|Mustelidae|{{taxlink|Mustela (Lutreola)|subgenus}}}}
- Lycophyta
{{taxon|division|kingdom|Plantae}}
{{taxon|phylum|subkingdom|Embryophyta}}
- Lycopodiopsida
{{taxon|class|division|Lycopodiophyta}}
{{taxon|class|subphylum|Lycopodiophytina}}
- Lyonia
{{taxon|genus|family|Ericaceae|certain flowering plants}}
{{taxon|genus|family|Monticuliferidae|certain fossil brachiopods}}
- Macgregoria
{{taxon|genus|family|Meliphagidae|{{vern|MacGregor's honeyeater}}, the only species}}
{{taxon|genus|family|Celastraceae|a kind of [[bittersweet]]}}
- Machaeridia
{{taxon|class|phylum|Annelida|the [[machaeridian]]s, extinct worms}}
{{taxon|genus|family|Acrididae|a type of [[grasshopper]] or [[locust]]}}
- Macleaya
{{taxon|genus|family|Papaveraceae|[[plume poppy]], of east Asia}}
{{taxon|subgenus|family|Culicidae|{{taxlink|Aedes (Macleaya)|subgenus}}}}
- Macroglossinae
{{taxon|subfamily|family|Sphingidae|certain [[moth]]s}}
{{taxon|subfamily|family|Pteropodidae|[[megabat]]s}}
- Macropsalis
{{taxon|genus|family|Caprimulgidae|{{vern|long-trained nightjar}}}}
{{taxon|genus|family|{{taxlink|Neopilionidae|family}}|{{synonym of|mul|{{taxlink|Megalopsalis|genus}}}}, certain [[daddy longlegs]] spiders}}
- Malacobdellidae
{{taxon|family|order|Monostilifera}}
{{taxon|family|order|Bdellonemertea}}
- Mallotus
{{taxon|genus|family|Euphorbiaceae|some trees related to [[spurge]], including the {{vern|kamala|novern=1}}}}
{{taxon|genus|family|Osmeridae|single [[fish]] species {{taxlink|Mallotus villosus|species}} ([[capelin]])}}
- Malvaceae
{{taxon|family|order|Malvales|many [[flowering plant]]s}}
{{taxon|clade|order|Malvales|{{ll|mul|core Malvales}}}}
- Manfreda
{{taxon|genus|family|Asparagaceae|now placed in genus ''{{ll|mul|Agave}}''}}
{{taxon|subgenus|family|Asparagaceae|{{taxlink|Agave subg. Manfreda|subgenus}}}}
- Manna
{{taxon|genus|family|Fabaceae|}}
{{taxon|genus|family|Cicadidae}}
- Mantophasmatodea
{{taxon|suborder|order|Notoptera}}
{{taxon|order|superorder|Polyneoptera}}
- Marchantiopsida
{{taxon|class|division|Marchantiophyta}}
{{taxon|class|phylum|Marchantiophyta}}
- Mastigophora
{{taxon|superclass|subphylum|Sarcomastigophora|many [[unicellular]] [[heterotrophic]] [[protozoan]]s}}
{{taxon|genus|family|Mastigophoraceae|a group of [[leafy liverwort]]s}}
- Megaviridae
{{taxon|family|kingdom|Virus|certain large DNA viruses}}
{{taxon|subfamily|family|Mimiviridae|i=1}}
- Melanogaster
{{taxon|genus|family|Syrphidae|certain hoverflies}}
{{taxon|genus|family|Melanogastraceae|certain fungi}}
- Melpomene
{{taxon|genus|family|Polypodiaceae|certain [[fern]]s}}
{{taxon|genus|family|Agelenidae|certain [[spider]]s}}
- Mentzelia
{{taxon|genus|family|{{taxlink|Loasaceae|family}}|certain [[flowering plant]]s of the [[America]]s, called [[blazingstar]]s or {{vern|stickleaf|pl=s}}}}
{{taxon|genus|family|{{taxlink|Spiriferinidae|family}}|certain extinct [[brachiopod]]s}}
- Mesitornithiformes
{{taxon|order|parvclass|Neognathae|}}
{{taxon|order|superorder|Neoaves}}
- Metamonada
{{taxon|phylum|superphylum|Eozoa}}
{{taxon|phylum|infrakingdom|Excavata}}
- Microdesmidae
{{taxon|family|order|Gobiiformes}}
{{taxon|family|order|Perciformes}}
- Micrognathozoa
{{taxon|phylum|kingdom|Animalia}}
{{taxon|class|phylum|Micrognathozoa}}
- Microsporidia
{{taxon|phylum|kingdom|Fungi|}}
{{taxon|phylum|subkingdom|Sarcomastigota}}
- Mimiviridae
{{taxon|family|order|{{taxlink|Imitervirales|order}}|i=1|}}
{{taxon|subfamily|family|Megaviridae|i=1}}
- Mimulus
{{taxon|genus|family|Phrymaceae|{{vern|monkey flower|pl=s}}}}
{{taxon|genus|family|{{taxlink|Epialtidae|family}}|{{vern|foliate kelp crab}} ({{taxlink|Mimulus foliatus|species}}), sometimes in ''[[Pugettia]]''}}
- Mollusca
{{taxon|phylum|superphylum|Protostomia}}
{{taxon|phylum|superphylum|Spiralia}}
- Monarda
{{taxon|genus|family|Lamiaceae|[[bee balm]] and other [[flowering plant]]s native to North America}}
{{taxon|genus|family|Sphingidae|{{taxlink|Monarda onyx|species}}, a [[moth]] of Mexico}}
- Mora
{{taxon|genus|family|Fabaceae|certain [[timber]] trees of the tropical Americas}}
{{taxon|genus|family|Moridae|[[common mora]], deep-sea fishes}}
- Mordacia
{{taxon|genus|family|Mordaciidae}}
{{taxon|genus|family|Petromyzontidae}}
- Morelia
{{taxon|genus|family|Rubiaceae|resembling and related to [[gardenia]]s}}
{{taxon|genus|family|Pythonidae|certain [[python]]s of Australia, New Guinea, and Indonesia}}
- Morella
{{taxon|genus|family|Myricaceae|}}
{{taxon|genus|family|Olpidiaceae|certain [[fungus|fungi]]}}
- Morganella
{{taxon|genus|family|Enterobacteriaceae|i=1|certain bacteria including the type species {{taxlink|Morganella morganii|species}}, a [[gram-negative]] [[bacterium]] that lives [[commensal]]ly in the intestinal tracts of reptiles and mammals, including humans}}
{{taxon|genus|family|Diaspididae|certain [[scale insect]]s}}
{{taxon|genus|family|Agaricaceae|certain [[puffball]] [[fungi]]}}
{{taxon|genus|family|{{taxlink|Araksalosiidae|family}}|certain fossil [[brachiopod]]s of the [[Devonian]] period}}
- Morina
{{taxon|genus|family|Caprifoliaceae|certain flowering plants}}
{{taxon|genus|family|Geometridae|certain moths}}
- Morus
{{taxon|genus|family|Sulidae|[[gannet]]s}}
{{taxon|genus|family|Moraceae|[[mulberry|mulberries]]}}
- Musophagiformes
{{taxon|order|class|Aves}}
{{taxon|order|subclass|Aves}}
- Mustelinae
{{taxon|subfamily|family|Mustelidae|[[wolverine]]s, [[weasel]]s, [[ferret]]s and [[marten]]s etc}}
{{taxon|subfamily|family|Mustelidae|[[weasel]]s, [[mink]]s, [[polecat]]s}}
- Mytilopsis
{{taxon|genus|family|{{taxlink|Dreissenidae|family}}|certain [[mussel]]s}}
{{taxon|genus|family|Lepidoziaceae|a group of [[liverwort]]s}}
- Myxini
{{taxon|class|subphylum|Hyperotreti}}
{{taxon|class|infraphylum|Agnatha}}
- Myxozoa
{{taxon|phylum|kingdom|Animalia}}
{{taxon|subphylum|phylum|Cnidaria}}
- Myzozoa
{{taxon|phylum|infrakingdom|Alveolata}}
{{taxon|subphylum|phylum|Miozoa}}
- Napaea
{{taxon|genus|family|Riodinidae|certain [[butterfly|butterflies]] of the tropical Americas}}
{{taxon|genus|family|Malvaceae|{{taxlink|Napaea dioica|species}} ({{vern|glade mallow}})}}
- Nauplius
{{taxon|genus|family|Cyclopidae|certain [[crustacean]]s, sometimes placed within ''[[Cyclops]]''}}
{{taxon|genus|family|Asteraceae|certain [[flowering]] [[plant]]s, sometimes included in ''[[Asteriscus]]''}}
- Necator
{{taxon|genus|family|{{taxlink|Corticiaceae|family}}|certain [[fungus|fungi]]}}
{{taxon|genus|family|Ancylostomatidae|common [[hookworm]]s that have [[buccal]] teeth resembling flat plates, that include internal [[parasite]]s of humans and various other [[mammal]]s, and that are probably of [[African]] origin though first identified in [[North America]]}}
- Nemertea
{{taxon|phylum|superphylum|Lophotrochozoa}}
{{taxon|phylum|superphylum|Spiralia}}
- Neoaves
{{taxon|clade|superorder|Neognathae|}}
{{taxon|superorder|infraclass|Neognathae}}
- Neogastropoda
{{taxon|order|class|Gastropoda}}
{{taxon|infraorder|suborder|Hypsogastropoda|}}
- Neognathae
{{taxon|superorder|infraclass|Neornithes}}
{{taxon|infraclass|subclass|Aves}}
- Neoptera
{{taxon|infraclass|clade|Metapterygota}}
{{taxon|infraclass|subclass|Pterygota}}
- Neuropterida
{{taxon|superorder|subdivision|Endopterygota|}}
{{taxon|superorder|infraclass|Neoptera}}
- Newtonia
{{taxon|genus|family|Fabaceae|certain [[legume]]s}}
{{taxon|genus|family|Vangidae|certain [[warbler]]s}}
- Nidularia
{{taxon|genus|family|Nidulariaceae|certain [[bird's nest fungus|bird's nest fungi]]}}
{{taxon|genus|family|Kermesidae|certain [[scale insect]]s}}
- Nitrospira
{{taxon|phylum|subkingdom|Negibacteria|i=1|now ''{{taxlink|Nitrospirota|phylum}}''}}
{{taxon|class|phylum|{{taxlink|Nitrospirota|phylum}}|i=1|[[tentative]] name}}
{{taxon|genus|family|Nitrospiraceae|i=1}}
- Norrisia
{{taxon|genus|family|Tegulidae|{{vern|Norris's top snail}}}}
{{taxon|genus|family|Loganiaceae|a tropical plant}}
- Notoptera
{{taxon|order|subclass|Pterygota|the [[grylloblattid]]s and [[gladiator]]s}}
{{taxon|genus|family|Asteraceae|{{taxlink|Otopappus|genus}}}}
- Nyssa
{{taxon|genus|family|Cornaceae}}
{{taxon|genus|family|Nyssaceae}}
- Nyssa sylvatica
{{taxon|species|family|Cornaceae}}
{{taxon|species|family|Nyssaceae}}
- Octopoda
{{taxon|order|superorder|Octopodiformes|}}
{{taxon|order|superorder|Octobrachia}}
- Odontophorus
{{taxon|genus|family|Odontophoridae|[[wood quail]]s}}
{{taxon|genus|family|Aizoaceae|certain [[ice plant]]s, now sometimes included in {{taxlink|Cheiridopsis|genus}}}}
- Oenanthe
{{taxon|genus|family|Apiaceae|[[water dropwort]]s}}
{{taxon|genus|family|Muscicapidae|[[wheatear]]s}}
- Oligochaeta
{{taxon|subclass|class|Clitellata|the [[earthworm]]s}}
{{taxon|genus|family|Asteraceae}}
- Olyra
{{taxon|genus|family|Bagridae|[[naked catfish]]es}}
{{taxon|genus|family|Poaceae|[[tropical]] [[bamboo]]s}}
- Onchocercidae
{{taxon|family|order|Spirurida}}
{{taxon|family|order|Rhabditida}}
- Onychopoda
{{taxon|suborder|order|Cladocera}}
{{taxon|suborder|order|Diplostraca}}
- Ophidia
{{taxon|order|class|Reptilia|[[snake]]s or [[serpent]]s, with no [[forelimb]]s and minimal manifestation of rear limbs, now {{l|mul|Serpentes}}}}
{{taxon|clade|subclass|Squamata|modern [[snake]]s and all reptiles more closely related to snakes than to other living groups of [[lizard]]s}}
- Opisthokonta
{{taxon|clade|superkingdom|Eukaryota|}}
{{taxon|supergroup|superkingdom|Eukaryota}}
- Opisthorchiidae
{{taxon|family|order|Plagiorchiida}}
{{taxon|family|order|Opisthorchiida}}
- Orania
{{taxon|genus|family|Arecaceae|certain [[palm]] trees of Southeast Asia, Madagascar, and New Guinea}}
{{taxon|genus|family|Muricidae|[[murex]] [[snail]]s or {{vern|rock snail|pl=s}}}}
- Orthoceras
{{taxon|genus|family|†{{taxlink|Orthoceratidae|family}}|formerly including many extinct [[nautiloid]] [[cephalopod]]s with straight shells,now only †{{taxlink|Orthoceras regulare|species}}}}
{{taxon|genus|family|Orchidaceae}}
- Owenia
{{taxon|genus|family|Meliaceae|certain plants}}
{{taxon|genus|family|Oweniidae|certain annelids}}
{{taxon|genus|family|Dinornithidae|certain birds}}
- Oxyuridae
{{taxon|family|order|Spirurida}}
{{taxon|family|order|Rhabditida}}
- Oxyuroidea
{{taxon|superfamily|order|Spirurida}}
{{taxon|superfamily|order|Rhabditida}}
- Padus
{{taxon|genus|family|Rosaceae|now a subgenus of ''{{l|mul|Prunus}}''}}
{{taxon|subgenus|family|Rosaceae|{{taxlink|Prunus subg. Padus|subgenus}}}}
- Pandinus
{{taxon|genus|family|Scorpionidae|approximately the same as the subgenus ''Pandinus'' in Pandinus (''sensu lato'')}}
{{taxon|genus|family|Scorpionidae|certain large [[scorpion]]s of tropical [[Africa]] and the southeastern [[Arabia]]n peninsula}}
{{taxon|subgenus|family|Scorpionidae|{{taxlink|Pandinus (Pandinus)|subgenus}}}}
- Paracoccus
{{taxon|genus|family|{{taxlink|Rhodobacteraceae|family}}|}}
{{taxon|genus|family|Pseudococcidae|certain [[mealybug]]s}}
- Paraneoptera
{{taxon|clade|infraclass|Neoptera|}}
{{taxon|superorder|infraclass|Neoptera}}
- Parkia
{{taxon|genus|family|Fabaceae|certain trees of western Africa, including [[African locust bean]]s}}
{{taxon|subgenus|family|Lutjanidae|certain [[snapper]]s of tropical reefs, {{taxlink|Lutjanus (Parkia)|subgenus}}}}
- Parlatoria
{{taxon|genus|family|Diaspididae|certain scales and mealybugs}}
{{taxon|genus|family|Brassicaceae|certain flowering plants}}
- Passerina
{{taxon|genus|family|Cardinalidae|North American [[bunting]]s}}
{{taxon|genus|family|Thymelaeaceae|South African shrubs and [[shrublet]]s}}
- Pelea
{{taxon|genus|family|Bovidae|{{taxlink|Pelea capreolus|species}} ({{vern|grey rhebok}})}}
{{taxon|genus|family|Rutaceae|[[now]] [[merge]]d into ''[[Melicope]]''}}
- Pellaea
{{taxon|genus|family|Pentatomidae|certain [[stinkbug]]s}}
{{taxon|genus|family|Pteridaceae|certain [[fern]]s called [[cliffbrake]]s}}
- Penicillus
{{taxon|genus|family|{{taxlink|Udoteaceae|family}}|certain [[alga]]e}}
{{taxon|genus|family|{{taxlink|Penicillidae|family}}}}
- Periploca
{{taxon|genus|family|{{taxlink|Cosmopterigidae|family}}|certain [[moth]]s}}
{{taxon|genus|family|Apocynaceae|certain plants}}
- Perrottetia
{{taxon|genus|family|Dipentodontaceae|certain [[rosid]]s}}
{{taxon|genus|family|Streptaxidae|certain carnivorous air-breathing [[snail]]s}}
- Pezizomycotina
{{taxon|subdivision|division|Ascomycota}}
{{taxon|subphylum|phylum|Ascomycota}}
- Phaeophyceae
{{taxon|class|phylum|Heterokontophyta}}
{{taxon|class|phylum|Ochrophyta}}
- Phoebe
{{taxon|genus|family|Lauraceae|tropical and subtropical [[evergreen]] trees, native to Asia and the Americas}}
{{taxon|genus|family|Cerambycidae|certain [[longhorn beetle]]s}}
- Pholidota
{{taxon|order|class|Mammalia|the [[pangolin]]s}}
{{taxon|genus|family|Orchidaceae|}}
- Phyllanthus
{{taxon|genus|family|Leiothrichidae|{{vern|Capuchin babbler}}, of forested tropical and subtropical Africa}}
{{taxon|genus|family|Phyllanthaceae|[[leafflower]]s, of all tropical and subtropical regions}}
- Phytophaga
{{taxon|clade|order|Coleoptera|almost all [[beetle]]s}}
{{taxon|genus|family|Cecidomyiidae|now in other genera of subfamily {{taxlink|Cecidomyiinae|subfamily}} of [[gall midge]]s, etc}}
- Pieris
{{taxon|genus|family|Ericaceae|certain [[shrub]]s, the [[andromeda]]s or [[fetterbush]]es}}
{{taxon|genus|family|Pieridae|the [[white]]s, typical [[pierid]] [[butterfly|butterflies]]}}
- Pinopsida
{{taxon|class|division|Pinophyta}}
{{taxon|class|superclass|Gymnospermae}}
- Piroplasmida
{{taxon|order|class|Aconoidasida}}
{{taxon|order|class|{{taxlink|Coccoidiomorphea|class}}}}
- Placentalia
{{taxon|subclass|class|Mammalia}}
{{taxon|infraclass|subclass|Theria}}
- Placozoa
{{taxon|phylum|subkingdom|Agnotozoa}}
{{taxon|phylum|kingdom|Animalia}}
{{taxon|class|phylum|Placozoa}}
- Plathymenia
{{taxon|genus|family|Fabaceae|certain [[legume]]s of eastern [[South America]]}}
{{taxon|genus|family|{{taxlink|Amphimeniidae|family}}|sole species {{taxlink|Plathymenia branchiosa|species}}, a [[solenogaster]] (shell-less [[mollusc]])}}
- Platyhelminthes
{{taxon|phylum|superphylum|Protostomia}}
{{taxon|phylum|superphylum|Spiralia}}
- Pleroma
{{taxon|genus|family|Melastomataceae|certain tropical plants}}
{{taxon|genus|family|{{taxlink|Pleromidae|family}}|certain [[sea sponge]]s}}
- Plumbago
{{taxon|genus|family|Plumbaginaceae|the [[leadwort]]s}}
{{taxon|genus|family|Hesperiidae|certain [[skipper]] butterflies}}
- Podocarpaceae
{{taxon|family|order|Pinales}}
{{taxon|family|order|Cupressales}}
- Pogonophora
{{taxon|class|phylum|Annelida|various [[annelid]] [[worm]]s that lack a [[digestive system]], now part of {{ll|mul|Siboglinidae}}}}
{{taxon|genus|family|{{taxlink|Peraceae|family}}}}
- Polybius
{{taxon|genus|family|{{taxlink|Polybiidae|family}}}}
{{taxon|genus|family|Portunidae}}
- Polybranchia
{{taxon|genus|family|Spionidae|certain [[polychaete]]s}}
{{taxon|genus|family|{{taxlink|Caliphyllidae|family}}|certain [[sea slug]]s}}
- Polyneoptera
{{taxon|superorder|infraclass|Neoptera}}
{{taxon|cohort|infraclass|Neoptera}}
- Polyphaga
{{taxon|suborder|order|Coleoptera|a very great number of [[beetle]]s having the [[prothoracic]] [[pleuron]] not externally visible but fused with the [[trochantin]]}}
{{taxon|genus|family|{{taxlink|Corydiidae|family}}|{{vern|sand cockroach|pl=es}}}}
- Polypodiopsida
{{taxon|class|division|Pteridophyta|[[leptosporangiate]] [[fern]]s}}
{{taxon|class|phylum|Tracheophyta|[[leptosporangiate]] ferns, [[horsetail]]s, [[whisk fern]]s, {{vern|grape fern|pl=s}}, and others}}
- Polystictus
{{taxon|genus|family|Tyrannidae|certain [[tyrant flycatcher]]s}}
{{taxon|genus|family|Hymenochaetaceae|certain [[fungus|fungi]]}}
- Poria
{{taxon|genus|family|Polyporaceae|certain fungi, now part of {{taxlink|Perenniporia|genus}}}}
{{taxon|genus|family|Coccinellidae|certain small [[beetle]]s}}
{{taxon|genus|family|{{taxlink|Canthocamptidae|family}}|now {{taxlink|Hanikraia|genus}}, a single species of [[crustacean]]}}
{{taxon|genus|family|{{taxlink|Hahniidae|family}}|now {{taxlink|Porioides|genus}}, certain {{vern|dwarf sheet spider|pl=s}}}}
- Porocystis
{{taxon|genus|family|Sapindaceae|certain trees of South America}}
{{taxon|genus|family|Dasycladaceae|certain extinct [[chlorophyte]]s}}
- Portlandia
{{taxon|genus|family|{{taxlink|Yoldiidae|family}}|certain [[bivalve]]s}}
{{taxon|genus|family|Rubiaceae|certain {{vern|bell flower|pl=s}}}}
- Priapulida
{{taxon|phylum|superphylum|Protostomia}}
{{taxon|phylum|superphylum|Ecdysozoa|also {{ll|mul|Priapula}}}}
- Pristimantis jamescameroni
{{taxon|species|family|{{taxlink|Strabomantidae|family}}}}
{{taxon|species|family|Craugastoridae}}
- Proboscidea
{{taxon|order|clade|Paenungulata|the [[elephant]]s}}
{{taxon|genus|family|Martyniaceae|certain [[New World]] flowering plants}}
- Proteus
{{taxon|genus|family|Proteidae|single [[amphibian]] species {{taxlink|Proteus anguinus|species}} (the [[olm]])}}
{{taxon|genus|family|Enterobacteriaceae|i=1|several [[bacteria]] responsible for human [[urinary tract]] infections}}
- Protococcus
{{taxon|genus|family|{{taxlink|Protococcaceae|family}}}}
{{taxon|genus|family|Chlamydomonadaceae}}
- Protostomia
{{taxon|superphylum|subkingdom|Eumetazoa}}
{{taxon|infrakingdom|subkingdom|Bilateria}}
- Protozoa
{{taxon|phylum|kingdom|Protista}}
{{taxon|kingdom|superkingdom|Eukaryota}}
- Prunella
{{taxon|genus|family|Prunellidae|[[accentor]]s}}
{{taxon|genus|family|Lamiaceae|[[selfheal]]}}
- Pseudofungi
{{taxon|phylum|superphylum|Heterokonta}}
{{taxon|subphylum|phylum|{{taxlink|Gyrista|phylum}}}}
- Psithyrus
{{taxon|genus|family|Apidae}}
{{taxon|subgenus|family|Apidae|''[[Bombus (Psithyrus)]]''}}
{{taxon|genus|family|Apidae}}
- Psocodea
{{taxon|superorder|subdivision|Paraneoptera|}}
{{taxon|order|superorder|Paraneoptera}}
- Psophodes
{{taxon|genus|family|Psophodidae|certain [[whipbird]]s}}
{{taxon|genus|family|{{taxlink|Cinclosomatidae|family}}|[[whipbird]]s and [[wedgebill]]s}}
- Pterygota
{{taxon|subclass|class|Insecta|[[winged]] [[insect]]s, also containing some secondarily wingless taxa.}}
{{taxon|genus|family|Malvaceae|certain [[mallow]]s}}
- Pulicomorpha
{{taxon|infraorder|order|Siphonaptera|many [[flea]]s}}
{{taxon|genus|family|Staphylinidae|certain [[rove beetle]]s}}
- Pythonomorpha
{{taxon|order|class|Reptilia|a group comprising [[snake]]s and [[mosasaur]]s}}
{{taxon|clade|order|Squamata}}
- Radiata
{{taxon|phylum|kingdom|Animalia}}
{{taxon|superphylum|subkingdom|Eumetazoa}}
- Radiozoa
{{taxon|subphylum|phylum|Retaria}}
{{taxon|infraphylum|phylum|Retaria}}
- Ramonda
{{taxon|genus|family|Gesneriaceae|certain flowering plants}}
{{taxon|subgenus|family|Tachinidae|certain {{vern|bristle fly|bristle flies}}; {{taxlink|Periscepsia (Ramonda)|subgenus}}}}
- Randia
{{taxon|genus|family|Bernieridae|{{vern|Rand's warbler}}}}
{{taxon|genus|family|Rubiaceae|the [[indigoberry|indigoberries]]}}
- Ranzania
{{taxon|genus|family|Molidae|{{vern|slender sunfish|pl=es}}}}
{{taxon|genus|family|Berberidaceae|only {{taxlink|Ranzania japonica|species}}}}
- Raphia
{{taxon|genus|family|Noctuidae|certain [[moth]]s}}
{{taxon|genus|family|Arecaceae|{{vern|raffia palm|pl=s}}}}
- Requienia
{{taxon|genus|family|Requieniidae|certain fossil molluscs}}
{{taxon|genus|family|Fabaceae|certain plants}}
- Rhabditophora
{{taxon|subphylum|phylum|Platyhelminthes}}
{{taxon|class|phylum|Platyhelminthes}}
- Rhabdocoela
{{taxon|order|class|Rhabditophora|}}
{{taxon|infraclass|class|Neoophora}}
- Rhabdophora
{{taxon|division|class|Hydrozoa| now considered a {{synonym of|en|nocap=1|{{taxlink|Graptolithina|subclass|†Graptolithina}}}}, certain of the [[Hemichordata]], known only from fossils}}
{{taxon|infraphylum|phylum|Ciliophora|certain [[protist]]s}}
- Rhamphorhynchus
{{taxon|genus|family|{{taxlink|Rhamphorhynchidae|family}}|a genus of long-tailed [[pterosaur]]s of the [[Jurassic]] period}}
{{taxon|genus|family|Orchidaceae|a genus of [[orchid]]s, now in {{taxlink|Aspidogyne|genus}}}}
- Rhaphidura
{{taxon|genus|family|Apodidae|certain [[spinetail]]s ([[swift]]s)}}
{{taxon|genus|family|Rubiaceae|the single species {{taxlink|Rhaphidura lowii|species}}}}
- Rhaphiodon
{{taxon|genus|family|{{taxlink|Cynodontidae|family}}|{{taxlink|Rhaphiodon vulpinus|species}} ({{vern|biara|novern=1}}, {{vern|vampire characin}}), a freshwater fish of tropical South America}}
{{taxon|genus|family|Lamiaceae|{{taxlink|Rhaphiodon echinus|species}}, a plant of eastern Brazil}}
- Rhizaria
{{taxon|infrakingdom|subkingdom|Biciliata}}
{{taxon|infrakingdom|subkingdom|Harosa}}
- Rhizocrinus
{{taxon|genus|family|{{taxlink|Bathycrinidae|family}}}}
{{taxon|genus|family|{{taxlink|Bourgueticrinidae|family}}}}
- Rhizoctonia
{{taxon|genus|kingdom|Fungi|about 100 species [[anamorphic]] [[fungus|fungi]] thought to be in the [[order]] [[Cantharellales]], now considered developmental stages of fungi from species in phyla [[Ascomycota]] and [[Basidiomycota]]}}
{{taxon|genus|family|{{taxlink|Ceratobasidiaceae|family}} |''[[Rhizoctonia solani]]'', the sole remaining accepted species}}
- Rhizoflagellata
{{taxon|order|class|Infusoria|[[flagellate]] [[infusoria]].}}
{{taxon|order|class|Archamoebea|{{ll|mul|Mastigamoebida}}}}
- Rhizopus
{{taxon|genus|family|{{taxlink|Rhizopodaceae|family}}}}
{{taxon|genus|family|Mucoraceae}}
- Rhodites
{{taxon|genus|family|Cynipidae|some now in {{taxlink|Diplolepis (Cynipidae)|genus|Diplolepis}}}}
{{taxon|subgenus|family|Cynipidae|{{taxlink|Diplolepis (Rhodites)|subgenus}}}}
- Rhodococcus
{{taxon|genus|family|Nocardiaceae|i=1|aerobic, non-[[sporulate|sporulating]], non-motile [[Gram-positive]] [[bacteria]]}}
{{taxon|genus|family|Coccidae|scale insects known as {{vern|soft scale|pl=s}}, {{vern|wax scale|pl=s}}, or {{vern|tortoise scale|pl=s}}}}
{{taxon|genus|family|Cyanidiaceae|certain [[alga]]e}}
- Rhodophyta
{{taxon|phylum|kingdom|Protista}}
{{taxon|phylum|kingdom|Plantae}}
- Rhodopis
{{taxon|genus|family|Trochilidae|the {{vern|oasis hummingbird}}}}
{{taxon|genus|family|Fabaceae|}}
- Rhombozoa
{{taxon|phylum|subkingdom|Agnotozoa}}
{{taxon|phylum|infrakingdom|Protostomia}}
- Rhombus
{{taxon|genus|order|Pleuronectiformes|certain [[flatfish]], now in {{taxlink|Scophthalmus|genus}} and other related genera}}
{{taxon|subgenus|family|Conidae|{{taxlink|Conus (Stephanoconus)|subgenus}}}}
- Ricinus
{{taxon|genus|family|Euphorbiaceae|the [[castor]] plant}}
{{taxon|genus|family|Ricinidae|several bird [[lice]]}}
- Rimula
{{taxon|genus|order|Helotiales}}
{{taxon|genus|family|Fissurellidae|certain [[keyhole limpet]]s or {{vern|slit limpet|pl=s}}}}
- Rivularia
{{taxon|genus|family|{{taxlink|Rivulariaceae|family}}|certain [[cyanobacteria]]}}
{{taxon|genus|family|Viviparidae|certain [[snail]]s, of China}}
- Rosmarinus
{{taxon|genus|family|Lamiaceae}}
{{taxon|subgenus|family|Lamiaceae|{{taxlink|Salvia subg. Rosmarinus|subgenus}}}}
- Rostellaria
{{taxon|genus|family|Strombidae|certain [[sea snail]]s; synonym of {{taxlink|Tibia|genus|nomul=1}}}}
{{taxon|section|family|Acanthaceae|{{taxlink|Justicia sect. Rostellaria|section}}}}
{{taxon|subsection|family|Acanthaceae|{{taxlink|Justicia subsect. Rostellaria|subsection}}}}
{{taxon|genus|family|Sapotaceae|now ''[[Sideroxylon]]''}}
- Rotifera
{{taxon|phylum|superphylum|Protostomia}}
{{taxon|phylum|superphylum|Spiralia}}
- Rupicola
{{taxon|genus|family|Cotingidae|[[cock-of-the-rock]]}}
{{taxon|genus|family|Ericaceae|flowering plants of [[Australia]]}}
- Saccorhiza
{{taxon|genus|family|{{taxlink|Phyllariaceae|family}}|certain [[brown alga]]e}}
{{taxon|genus|family|{{taxlink|Hippocrepinidae|family}}|certain [[foraminifera]]}}
- Sagitta
{{taxon|genus|family|{{taxlink|Sagittidae|family}}|typical marine [[arrow worm]]s}}
{{taxon|genus|family|Alismataceae|[[arrowhead]]s or [[duck potatoes]], now ''[[Sagittaria]]''}}
- Saintpaulia
{{taxon|genus|family|Gesneriaceae}}
{{taxon|section|family|Gesneriaceae|{{taxlink|Streptocarpus sect. Saintpaulia|section}}}}
- Salacia
{{taxon|genus|family|Celastraceae|certain climbing plants of the tropics}}
{{taxon|genus|family|Sertulariidae|certain [[cnidarian]]s}}
{{taxon|genus|class|Bacillariophyceae|a certain poorly known [[chromist]]}}
- Salomonia
{{taxon|genus|family|{{taxlink|Aphrophoridae|family}}|certain [[true bug]]s}}
{{taxon|genus|family|Polygalaceae|certain [[milkwort]]s}}
- Salpinctes
{{taxon|genus|family|Troglodytidae|the [[rock wren]]}}
{{taxon|genus|family|Apocynaceae|including {{vern|rocktrumpet|pl=s}}, now in genus {{taxlink|Mandevilla|genus}}}}
- Salvadora
{{taxon|genus|family|Colubridae|the [[patchnose snake]]s}}
{{taxon|genus|family|Salvadoraceae|trees and shrubs native to the [[Middle East]]}}
- Sarcocystidae
{{taxon|family|order|Eucoccidiorida}}
{{taxon|family|order|Eimerida}}
- Sarcophaga
{{taxon|genus|family|Sarcophagidae|[[flesh fly|flesh flies]]}}
{{taxon|suborder|superorder|Marsupialia|[[carnivorous]] and [[insectivorous]] [[marsupial]]s including the [[dasyure]]s and the [[opossum]]s}}
- Sarcopterygii
{{taxon|class|superclass|Osteichthyes}}
{{taxon|superclass|phylum|Chordata}}
- Satureia
{{taxon|genus|family|Encyrtidae|certain parasitic [[chalcid wasp]]s}}
{{taxon|genus|family|Lamiaceae|the [[savory|savories]], now ''[[Satureja]]''}}
- Satyrium
{{taxon|genus|family|Lycaenidae|certain [[butterfly|butterflies]]}}
{{taxon|genus|family|Orchidaceae|certain [[orchid]]s, principally of sub-Saharan Africa}}
- Saurodon
{{taxon|genus|family|{{taxlink|Ichthyodectidae|family}}}}
{{taxon|genus|family|{{taxlink|Saurodontidae|family}}}}
- Scaphium
{{taxon|genus|family|Malvaceae|[[nut]] trees of southeast Asia}}
{{taxon|genus|family|Staphylinidae}}
- Schaefferia
{{taxon|genus|family|Celastraceae}}
{{taxon|genus|family|{{taxlink|Hypogastruridae|family}}|certain [[springtail]]s}}
- Schistosomatidae
{{taxon|family|order|Diplostomida}}
{{taxon|family|order|Strigeidida}}
- Schlegelia
{{taxon|genus|family|Paradisaeidae|[[Wilson's bird of paradise]]}}
{{taxon|genus|family|{{taxlink|Schlegeliaceae|family}}|plants of the [[New World]] tropics}}
- Schrankia
{{taxon|genus|family|Erebidae|certain [[moth]]s}}
{{taxon|genus|family|Fabaceae|certain American leguminous plants, including the {{vern|sensitive briar}}}}
- Sciurus
{{taxon|genus|family|Sciuridae|[[squirrel]]s}}
{{taxon|subgenus|genus|Sciurus}}
- Scoparia
{{taxon|genus|family|Plantaginaceae|{{vern|licorice weed}} and close relatives}}
{{taxon|genus|family|Crambidae|certain [[moth]]s}}
- Scoria
{{taxon|genus|family|Geometridae|certain [[moth]]s now in genus {{taxlink|Siona|genus}}}}
{{taxon|genus|family|Juglandaceae|certain hickory trees, now in genus ''[[Carya]]''}}
- Scorpiurus
{{taxon|genus|family|Fabaceae|plants call {{vern|scorpion's tail|pl=s}}}}
{{taxon|genus|family|{{taxlink|Dolichopodidae|family}}|certain flies native to [[New Zealand]]}}
- Scutiger
{{taxon|genus|family|{{taxlink|Albatrellaceae|family}}|certain [[fungus|fungi]]}}
{{taxon|genus|family|Megophryidae|certain [[toad]]s}}
- Selenites
{{taxon|genus|family|Coccinellidae|certain [[Old World]] [[ladybird]] [[beetle]]s, now {{taxlink|Cheilomenes|genus}}}}
{{taxon|genus|family|{{taxlink|Haplotrematidae|family}}|certain land [[snail]]s, now genus {{taxlink|Zophos|genus}}}}
- Semele
{{taxon|genus|family|Semelidae|numerous species of {{vern|venus shell|pl=s}}}}
{{taxon|genus|family|Asparagaceae|of the Canary Islands and Madeira}}
- Sericostoma
{{taxon|genus|family|{{taxlink|Sericostomatidae|family}}|typical {{vern|bushtailed caddisfly|bushtailed caddisflies}}}}
{{taxon|genus|family|Boraginaceae}}
- Serpentes
{{taxon|suborder|order|Squamata}}
{{taxon|order|class|Reptilia}}
- Serpula
{{taxon|genus|family|Serpulidae|[[sessile]] [[marine]] [[annelid]] [[tube worm]]s}}
{{taxon|genus|family|{{taxlink|Serpulaceae|family}}|certain [[fungus|fungi]], including that causing [[dry rot]] in structural timber}}
- Sicarius
{{taxon|genus|family|{{taxlink|Sicariidae|family}}|certain [[recluse spider]]s}}
{{taxon|genus|family|{{taxlink|Habronematidae|family}}|certain [[nematode]]s; {{synonym of|mul|{{taxlink|Lispirurus|genus}}}}}}
- Sida
{{taxon|genus|family|{{taxlink|Sididae|family}}|certain [[cladoceran]] [[water flea]]s}}
{{taxon|genus|family|Malvaceae|certain [[flowering plant]]s, called [[sida]]s or [[fanpetal]]s}}
- Sipuncula
{{taxon|phylum|superphylum|Protostomia}}
{{taxon|phylum|superphylum|Spiralia}}
- Solenopsis
{{taxon|genus|family|Formicidae|includes some of the [[fire ant]]s}}
{{taxon|genus|family|Campanulaceae|native to the [[Mediterranean]] area}}
- Solitaria
{{taxon|genus|family|Teloschistaceae|certain lichens}}
{{taxon|genus|family|Caryophyllaceae|certain plants, now {{taxlink|Shivparvatia|genus}}}}
{{taxon|order|phylum|Entoprocta|formerly used for certain [[entoproct]]s}}
- Soricomorpha
{{taxon|order|class|Mammalia|}}
{{taxon|suborder|order|Eulipotyphla}}
- Sphaeroides
{{taxon|genus|family|Tetraodontidae|[[Sphoeroides]]}}
{{taxon|genus|family|Ceratostomataceae|{{taxlink|Sphaerodes|genus}}, a marine fungus}}
- Sphaerotheca
{{taxon|genus|family|Dicroglossidae|certain true frogs}}
{{taxon|genus|family|Erysiphaceae|certain fungi}}
- Sphagnopsida
{{taxon|class|division|Bryophyta}}
{{taxon|class|phylum|Bryophyta}}
- Spirochaetes
{{taxon|phylum|kingdom|Bacteria|i=1}}
{{taxon|class|phylum|Spirochaetes|i=1}}
- Spirulina
{{taxon|genus|family|{{taxlink|Pseudanabaenaceae|family}}|i=1|certain [[cyanobacteria]]}}
{{taxon|suborder|order|Spirulida|certain [[mollusc]]s, with only ''[[Spirula spirula]]'' being extant}}
- Spiruria
{{taxon|subclass|class|Secernentea}}
{{taxon|suborder|order|Rhabditida|often [[Spirurina]]}}
- Spirurida
{{taxon|order|class|Secernentea|}}
{{taxon|order|class|Chromadorea}}
- Sporozoa
{{taxon|infraphylum|phylum|Myzozoa}}
{{taxon|superclass|phylum|Miozoa}}
- Squamata
{{taxon|order|superorder|Lepidosauria}}
{{taxon|subclass|class|Reptilia}}
- Stagnicola
{{taxon|genus|family|Lymnaeidae|certain freshwater snails}}
{{taxon|genus|family|Mythicomycetaceae|certain fungi}}
- Stanleya
{{taxon|genus|family|Brassicaceae|[[prince's plume]]}}
{{taxon|genus|family|Paludomidae|certain freshwater snails}}
- Stegocephalia
{{taxon|order|class|Amphibia|all [[extinct]] large [[salamander]]-like [[amphibian]]s, the [[Labyrinthodontia]]}}
{{taxon|clade|clade|Tetrapodomorpha|containing all [[vertebrate]]s with [[toe]]s rather than [[fin]]s, as well as a few of the most closely related [[lobe-finned]] [[fish]]}}
- Stelis
{{taxon|genus|family|Orchidaceae|[[leach orchid]]s}}
{{taxon|genus|family|Megachilidae|[[dark bee]]s}}
- Sterna
{{taxon|genus|family|Laridae|many {{vern|white tern|pl=s}}, including '''''Sterna''''' sensu stricto and others now placed in genera ''{{l|mul|Onychoprion}}'', ''{{l|mul|Sternula}}'', and ''{{l|mul|Thalasseus}}''}}
{{taxon|genus|family|Laridae}}
{{taxon|genus|family|Sternidae}}
- Stratiotes
{{taxon|genus|family|Hydrocharitaceae|certain aquatic plants, [[water soldier]]s}}
{{taxon|genus|family|Carabidae|certain beetles}}
- Strepsiptera
{{taxon|order|class|Insecta}}
{{taxon|order|superorder|Holometabola}}
- Strongylida
{{taxon|suborder|order|Rhabditida}}
{{taxon|order|class|Chromadorea}}
- Strongyloididae
{{taxon|family|order|Panagrolaimida}}
{{taxon|family|order|Rhabditida}}
- Stylommatophora
{{taxon|infraorder|order|Pulmonata}}
{{taxon|order|subclass|Heterobranchia}}
- Sybra
{{taxon|genus|family|Cerambycidae}}
{{taxon|subgenus|genus|Sybra}}
- Sylviidae
{{taxon|family|order|Passeriformes|the {{vern|sylviid babbler}}s (and formerly [[parrotbill]]s and {{vern|myzornis}})}}
{{taxon|family|order|Passeriformes|all of the {{vern|Old World warbler}}s}}
- Sylvilagus
{{taxon|genus|family|Leporidae|{{vern|cottontail rabbit|pl=s}}}}
{{taxon|subgenus|genus|Sylvilagus}}
- Tabebuia
{{taxon|genus|family|Bignoniaceae|trees including certain [[trumpet tree]]s, [[ipe]], [[pau d'arco|pau d’arco]], and {{l|en|lapacho}}}}
{{taxon|genus|family|Bignoniaceae|excluding species now in ''{{ll|mul|Handroanthus}}'' and {{taxlink|Roseodendron|genus}}}}
- Talaromyces
{{taxon|genus|family|Aspergillaceae}}
{{taxon|genus|family|Trichocomaceae}}
- Tanna
{{taxon|genus|family|Cicadidae|[[cicada]]s of Asia}}
{{taxon|genus|family|Salticidae|certain [[jumping spider]]s, renamed in 2006 to {{taxlink|Araneotanna|genus}}}}
- Tardigrada
{{taxon|phylum|superphylum|Ecdysozoa|[[tardigrade]]s, [[water bear]]s, or [[moss piglet]]s, small, hardy animals found in many kinds of environments}}
{{taxon|order|class|Mammalia|[[sloth]]s and [[sloth bear]]s}}
- Tatera
{{taxon|genus|family|Muridae|{{vern|Indian gerbil}}}}
{{taxon|genus|family|Muridae|African and Asian gerbils, all but ''T. indica'' now in {{taxlink|Gerbilliscus|genus}}}}
- Taxaceae
{{taxon|family|order|Pinales}}
{{taxon|family|order|Cupressales}}
- Tectaria
{{taxon|genus|family|Tectariaceae|the {{vern|halberd fern|pl=s}}}}
{{taxon|genus|family|Littorinidae|[[univalve]]s with a [[turbinate]] or [[conic]] [[shell]], now {{taxlink|Tectarius|genus}}}}
- Teleostei
{{taxon|infraclass|subclass|Neopterygii}}
{{taxon|class|superclass|Actinopterygii}}
- Tephrosia
{{taxon|genus|family|Fabaceae|[[hoarypea]], [[goat's rue]], [[devil's shoestring]]}}
{{taxon|genus|family|Geometridae|now a {{synonym of|mul|''[[Ectropis]]''|nocap=1}}}}
- Tetilla
{{taxon|genus|family|{{taxlink|Francoaceae|family}}|a [[monotypic]] genus containing {{taxlink|Tetilla hydrocotylifolia|species}}, an [[herb]] from [[Chile]] known as the [[bridal wreath]]}}
{{taxon|genus|family|{{taxlink|Tetillidae|family}}|certain {{vern|golf ball sponge|pl=s}}}}
- Tetramera
{{taxon|group|order|Coleoptera|such [[beetle]]s}}
{{taxon|division|family|{{taxlink|Chalcididae|family}}}}
- Tetrapodomorpha
{{taxon|subclass|class|Sarcopterygii|the [[sarcopterygian]]s; the [[tetrapod]]s and some [[osteolepiform]]s}}
{{taxon|subclass|class|Sarcopterygii|all [[Tetrapoda]] and various extinct relatives more closely related to them than to [[coelacanth]]s, [[lungfish]], and their extinct relatives}}
- Teuthis
{{taxon|genus|family|Loliginidae|''{{ll|mul|Loligo}}'', certain [[squid]]}}
{{taxon|genus|family|Siganidae|now genus ''[[Siganus]]''}}
{{taxon|genus|family|Acanthuridae|''{{ll|mul|Acanthurus}}''}}
- Thalia
{{taxon|genus|family|Salpidae|certain [[salp]]s}}
{{taxon|genus|family|Marantaceae|{{vern|alligator flag|pl=s}}}}
- Thamnophilus
{{taxon|genus|family|Thamnophilidae|certain [[antshrike]]s}}
{{taxon|genus|family|Curculionidae|certain [[beetle]]s}}
- Thapsia
{{taxon|genus|family|{{taxlink|Urocyclidae|family}}|certain air-breathing [[land snail]]s}}
{{taxon|genus|family|Apiaceae|[[deadly carrot]]s}}
- Thapsinillas
{{taxon|genus|family|Pycnonotidae}}
{{taxon|subgenus|family|Pycnonotidae|{{taxlink|Alophoixus (Thapsinillas)|subgenus}}}}
- Thaumarchaeota
{{taxon|phylum|kingdom|Archaea|i=1}}
{{taxon|class|phylum|Crenarchaeota|i=1}}
- Thermodesulfobacteria
{{taxon|division|kingdom|Bacteria|i=1}}
{{taxon|phylum|subkingdom|Negibacteria|i=1}}
{{taxon|class|phylum|Thermodesulfobacteria|i=1}}
- Thermotogae
{{taxon|phylum|kingdom|Bacteria}}
{{taxon|class|phylum|Thermotogae|i=1}}
- Thymus
{{taxon|genus|family|Lamiaceae|[[thyme]]}}
{{taxon|genus|family|Eulophidae}}
- Tillodontia
{{taxon|suborder|order|{{taxlink|Trogonta|order}}}}
{{taxon|suborder|order|{{taxlink|Cimolesta|order}}}}
- Townsendia
{{taxon|genus|family|Asilidae|certain [[robber fly|robber flies]]}}
{{taxon|genus|family|Asteraceae|[[Townsend daisy|Townsend daisies]]}}
- Trachelium
{{taxon|genus|family|Alydidae|certain [[broad-headed bug]]s}}
{{taxon|genus|family|Campanulaceae}}
- Tracheophyta
{{taxon|division|kingdom|Plantae}}
{{taxon|phylum|superphylum|Embryophyta}}
- Trachinoidei
{{taxon|order|superorder|Acanthopterygii}}
{{taxon|suborder|order|Perciformes}}
- Trachyphyllum
{{taxon|section|family|Saxifragaceae|{{taxlink|Saxifraga sect. Trachyphyllum|section}}, formerly a genus}}
{{taxon|genus|family|{{taxlink|Pterigynandraceae|family}}|certain {{vern|feather moss}}es}}
- Trematoda
{{taxon|class|phylum|Platyhelminthes}}
{{taxon|infraclass|class|Neoophora}}
- Trentepohlia
{{taxon|genus|family|Trentepohliaceae|certain [[green alga]]e}}
{{taxon|genus|family|{{taxlink|Limoniidae|family}}|certain [[cranefly|craneflies]]}}
- Treponema
{{taxon|genus|family|{{taxlink|Treponemataceae|family}}|i=1}}
{{taxon|genus|family|Spirochaetaceae|i=1}}
- Tribolium
{{taxon|genus|family|Poaceae|various [[grass]]es}}
{{taxon|genus|family|Tenebrionidae|certain [[flour beetle]]s}}
- Trichas
{{taxon|genus|family|Pycnonotidae|''[[Criniger]]'' (certain [[greenbul]]s)}}
{{taxon|genus|family|Parulidae|''[[Geothlypis]]'' ([[yellowthroat]]s)}}
- Trichia
{{taxon|genus|family|{{taxlink|Trichiaceae|family}}|certain [[plasmodial]] [[slime mold]]s}}
{{taxon|genus|family|Erebidae|certain [[noctuid]] [[moth]]s}}
- Trichinellidae
{{taxon|family|order|Trichocephalida}}
{{taxon|family|order|Trichinellida}}
- Trichomonadida
{{taxon|order|class|Parabasalia}}
{{taxon|order|class|{{taxlink|Trichomonadea|class}}}}
- Trichuridae
{{taxon|family|order|Trichocephalida}}
{{taxon|family|order|Trichinellida}}
- Tricladida
{{taxon|order|class|Turbellaria}}
{{taxon|order|infraclass|Adiaphanida}}
- Trigona
{{taxon|genus|family|Apidae|three species of [[vulture bee]]s and many other [[stingless bee]]s}}
{{taxon|subgenus|family|Apidae|{{taxlink|Trigona (''Trigona'')|subgenus}}}}
- Trigonia
{{taxon|genus|family|{{taxlink|Trigoniidae|family}}|certain [[extinct]] [[saltwater]] [[clam]]s}}
{{taxon|genus|family|{{taxlink|Trigoniaceae|family}}|certain flowering plants}}
- Trimera
{{taxon|division|order|Coleoptera|[[beetle]]s with three-jointed [[tarsus|tarsi]]}}
{{taxon|section|family|{{taxlink|Chalcididae|family}}|in subfamily {{taxlink|Trichogramminae|subfamily}}}}
- Triodia
{{taxon|genus|family|Poaceae|grasses of arid parts of Australia, some of the [[spinifex]]es, [[porcupine grass]]}}
{{taxon|genus|family|Hepialidae|certain [[moth]]s}}
- Triton
{{taxon|genus|family|{{taxlink|Tritonidae|family}}|{{vern|triton snail|pl=s}}, now in the [[genus]] {{taxlink|Charonia|genus}} (family {{taxlink|Ranellidae|family}})}}
{{taxon|genus|family|Salamandridae|certain [[newt]]s, [[eft]]s, and [[salamander]]s}}
- Tritonia
{{taxon|genus|family|Iridaceae|[[flame freesia]]s}}
{{taxon|genus|family|Tritoniidae|certain sea slugs}}
- Trochus
{{taxon|genus|family|Trochidae|certain [[trochus]], or [[topshell]], [[snail]]s}}
{{taxon|genus|subclass|Bacillariophyceae|an extinct [[ochrophyte]] [[alga]]}}
- Troglodytes
{{taxon|genus|family|Troglodytidae|a number of [[songbird]]s, including the [[Eurasian wren]]}}
{{taxon|genus|family|Hominidae|a former genus, now synonymized with ''[[Pan]]''}}
- Truncatella
{{taxon|genus|family|Truncatellidae|certain land snails}}
{{taxon|genus|family|Sporocadaceae|certain plant pathogens}}
- Urceolaria
{{taxon|genus|order|Pezizales}}
{{taxon|genus|family|{{taxlink|Urceolariidae|family}}|in chromist order {{taxlink|Mobilida|order}}}}
- Urva
{{taxon|genus|family|Herpestidae|''[[Herpestes]]'' — formerly the sole [[mongoose]] genus}}
{{taxon|genus|family|Herpestidae|{{vern|Asian mongoose|pl=s}}}}
- Valonia
{{taxon|genus|family|{{taxlink|Valoniaceae|family}}|several species of [[green alga]]e with [[succulent]] [[thallus|thalli]]}}
{{taxon|genus|family|{{taxlink|Platystomatidae|family}}|two species of [[signal fly|signal flies]]}}
- Vampyrellidae
{{taxon|family|order|{{taxlink|Aconchulinida|order}}}}
{{taxon|family|order|{{taxlink|Vampyrellida|order}}}}
- Vandellia
{{taxon|genus|family|{{taxlink|Trichomycteridae|family}}|certain parasitic {{l|en|catfish}}}}
{{taxon|genus|family|{{taxlink|Linderniaceae|family}}}}
{{taxon|genus|family|Scrophulariaceae|now mostly in {{taxlink|Lindernia|genus}} (family {{taxlink|Linderniaceae|family}})}}
- Venturia
{{taxon|genus|family|{{taxlink|Venturiaceae|family}}|certain fungi, many of which are plant [[pathogen]]s}}
{{taxon|genus|family|Ichneumonidae|certain [[wasp]]s}}
- Verrucomicrobia
{{taxon|phylum|subkingdom|Negibacteria|i=1}}
{{taxon|phylum|group|PVC group|i=1}}
- Vesicularia
{{taxon|genus|family|Hypnaceae|certain mosses}}
{{taxon|genus|family|{{taxlink|Vesiculariidae|family}}|certain bryozoans}}
- Vespula
{{taxon|genus|family|Vespidae|some of the [[social]] [[wasp]]s called [[yellowjacket]]s}}
{{taxon|subgenus|family|Vespidae|{{taxlink|Vespula subg. Vespula|subgenus}}}}
- Victoria
{{taxon|genus|family|Nymphaeaceae|certain [[waterlily|waterlilies]] with very large flat leaves, native to the Amazon}}
{{taxon|genus|family|Geometridae|certain [[moth]]s native to Africa}}
{{taxon|genus|order|{{taxlink|Palaeocopida|order}}|{{taxlink|Soleaua|genus}}, fossil crustaceans}}
{{taxon|genus|family|Scarabaeidae|certain [[scarab beetles]]; a junior synonym of the genus {{taxlink|Hoplia|genus}}}}
- Viola
{{taxon|genus|family|Violaceae|[[violet]]s}}
{{taxon|genus|family|Hesperiidae|certain of the butterflies called [[skipper]]s}}
- Williamsonia
{{taxon|genus|family|Corduliidae|[[boghaunter]]s}}
{{taxon|genus|family|Williamsoniaceae|certain extinct plants}}
- Wilsonia
{{taxon|genus|family|Parulidae|synonym of ''[[Setophaga]]'', certain New World [[warbler]]s}}
{{taxon|genus|family|Convolvulaceae|perennial [[subshrub]]s, native to Australia}}
- Xanthorrhoea
{{taxon|genus|family|Xanthorrhoeaceae}}
{{taxon|genus|family|Asphodelaceae}}
- Xanthorrhoeaceae
{{taxon|family|order|Asparagales|the [[grass tree]]s}}
{{taxon|family|order|Asparagales|the [[grass tree]]s, [[daylily|daylilies]], and diverse related plants that produce [[anthraquinone]]s and have flowers of long leafless stalks known as [[scape]]s}}
- Xenopeltidae
{{taxon|family|order|Serpentes|{{vern|sunbeam snake|pl=s}}, related to [[python]]s}}
{{taxon|family|superfamily|Booidea}}
{{taxon|family|superfamily|{{taxlink|Henophidea|superfamily}}}}
- Xenus
{{taxon|genus|family|Scolopacidae|the [[Terek sandpiper]] of north central Eurasia}}
{{taxon|genus|order|Pyrenulales|a [[fungus]]}}
- Xerophyllum
{{taxon|genus|family|Melanthiaceae|certain perennial plants}}
{{taxon|genus|family|Tetrigidae|certain pygmy grasshoppers}}
- Ximenia americana
{{taxon|species|family|{{taxlink|Olacaceae|family}}}}
{{taxon|species|family|{{taxlink|Ximeniaceae|family}}}}
- Xyleborus
{{taxon|genus|family|{{taxlink|Stereocaulaceae|family}}|certain [[lichen]]-forming fungi}}
{{taxon|genus|family|Curculionidae|various [[ambrosia beetle]]s}}
- Yersinia
{{taxon|genus|family|Enterobacteriaceae|i=1|certain [[bacterium|bacteria]] hosted especially by [[rodent]]s, some [[pathogenic]] to humans}}
{{taxon|genus|family|Mantidae|the single species {{taxlink|Yersinia mexicana|species}}}}
- Zebrina
{{taxon|genus|family|Enidae|certain air-breathing [[snail]]s}}
{{taxon|genus|family|Commelinaceae|the [[wandering Jew]] plants}}
- Zeus
{{taxon|genus|family|Zeidae|[[John Dory]] and {{vern|Cape dory}}}}
{{taxon|genus|family|{{taxlink|Rhytismataceae|family}}|a [[fungus]] discovered on Mount Olympus, with yellow disc-shaped fruiting bodies that grow in the decaying wood of Bosnian pine trees}}
- Zilla
{{taxon|genus|family|Brassicaceae|one or more species of desert flowers of the [[Sahara]] and Arabia}}
{{taxon|genus|family|Araneidae|certain {{vern|orb-weaver spider}}s}}
- Zonaria
{{taxon|genus|family|{{taxlink|Dictyotaceae|family}}|certain [[thalloid]] [[brown alga]]e}}
{{taxon|genus|family|Cypraeidae|certain [[sea snail]]s}}
- Zonotrichia
{{taxon|genus|family|Passerellidae|{{vern|crowned sparrow|pl=s}}}}
{{taxon|genus|family|{{taxlink|Rivulariaceae|family}}|considered a synonym of ''[[Rivularia]]''; certain [[cyanobacteria]]}}
- Zoraptera
{{taxon|order|subclass|Pterygota}}
{{taxon|order|superorder|Polyneoptera}}
- Zygaena
{{taxon|genus|family|Zygaenidae|[[burnet moth]]s}}
{{taxon|genus|family|Sphyrnidae|''{{l|mul|Sphyrna}}'', [[hammerhead shark]]s}}
- Zygentoma
{{taxon|order|subclass|Apterygota}}
{{taxon|order|subclass|Dicondylia}}
- Zygnematales
{{taxon|order|division|Charophyta}}
{{taxon|order|class|Conjugatophyceae}}