one of two usually recognized orders of true bacteria; Gram-positive spherical or rod-shaped forms; some are motile; in some classifications considered an order of Schizomycetes

one of two usually recognized orders of true bacteria; Gram-negative spiral or spherical or rod-shaped bacteria usually motile by polar flagella; some contain photosynthetic pigments

pleomorphic Gram-negative microorganisms

coextensive with the family Mycoplasmataceae

filamentous or rod-shaped bacteria

an order of higher bacteria

higher bacteria; slender spiral rodlike forms

mostly freshwater protozoa

marine protozoa

the animal order including amoebas

foraminifers

testacean rhizopods

coextensive with the family Fucaceae

pond scums; desmids

in some classifications considered a phylum of the kingdom Protista; in others included in the plant phylum Pyrrophyta

cellulose-producing flagellates

small usually parasitic flagellates

an order in the subclass Telosporidia

an order in the subclass Telosporidia

an order in the subclass Telosporidia

imperfectly known parasites of the muscles of vertebrates

an order in the subclass Acnidosporidia

parasites of worms

an order in the subclass Cnidosporidia

an order in the subclass Cnidosporidia

an extensive group of teleost fishes having fins supported by flexible cartilaginous rays

an order of animals including almost entirely freshwater fishes: characins; loaches; carp; suckers; sometimes classified as a suborder of Ostariophysi

an order of spiny-finned fish in the superorder Acanthopterygii

dories

bellows fishes; shrimpfishes; cornetfishes; pipefishes; small order of chiefly tropical marine fishes of varied and bizarre form all having a small mouth at the end of a drawn-out tubular snout

extinct group of armored jawless vertebrates; taxonomy is not clear

extinct group of armored jawless fishes or fish-like vertebrate; taxonomy is not clear

extinct group of armored fish-like vertebrates; taxonomy is not clear

extinct order of jawless vertebrates

extinct order of primitive vertebrates; the precise taxonomy is not clear; in some classifications considered a separate phylum

primitive jawless aquatic vertebrate: lampreys; hagfishes

lampreys as distinguished from hagfishes

hagfishes as distinguished from lampreys

rays with bodies shaped like torpedoes

fish with dorsoventrally flattened bodies; includes: rays; skates; guitarfishes; sawfishes

used in former classifications to include all ratite bird orders

a ratite bird order: ostriches and related extinct birds; known from the Pleistocene onward

a ratite bird order: cassowaries and emus

a ratite bird order: flightless ground birds having vestigial wings and long bills and small eyes: kiwis

a ratite bird order: birds intermediate in characteristics between ostriches and emus: recent and extinct rheas

huge extinct flightless birds: elephant birds

a ratite bird order: recently extinct flightless birds of New Zealand

a bird with feet adapted for perching (as on tree branches); this order is now generally abandoned by taxonomists

largest order of birds comprising about half the known species; rooks; finches; sparrows; tits; warblers; robins; wrens; swallows; etc.; the four suborders are Eurylaimi and Tyranni and Menurae and Oscines or Passeres

two names for the suborder of typical songbirds

lyrebirds and scrubbirds

broadbills

New World flycatchers; antbirds; oven birds; woodhewers

used in some classification systems; a suborder or superfamily nearly coextensive with suborder Tyranni; Passeriformes having relatively simple vocal organs and little power of song; clamatorial birds

term used in former classifications; erroneously grouped together birds of the orders Falconiformes and Strigiformes

chiefly diurnal carnivorous birds having hooked beaks and long talons with opposable hind toe: falcons; hawks; eagles; ospreys; caracaras; vultures

owls

salamanders; newts; congo snakes

frogs, toads, tree toads

an order of amphibians including caecilians

extinct amphibians typically resembling heavy-bodied salamanders or crocodiles and having a solid flattened skull and conical teeth; Devonian through Triassic

formerly a suborder of Stegocephalia; amphibia having vertebrae whose component elements are fused into a single piece

in former classifications a division of class Amphibia comprising all pre-Jurassic and some later extinct large salamandriform amphibia

formerly a suborder of Stegocephalia; large Carboniferous and Permian amphibians having vertebrae in which some elements remain separate

tortoises and turtles

tuataras; extinct forms from middle Triassic

diapsid reptiles: snakes and lizards

true lizards; including chameleons and geckos

crocodiles; alligators; caimans; gavials

former name for the order Crocodylia

extinct terrestrial reptiles having bird-like pelvises: armored dinosaurs (thyreophorans); boneheaded and horned dinosaurs (marginocephalians); duck-billed dinosaurs (euronithopods)

armored dinosaurs: stegosaurs and ankylosaurs

includes boneheaded (pachycephalosaurs) and horned (ceratopsian) dinosaurs

boneheaded dinosaurs; late Cretaceous

horned dinosaurs

widespread group including duck-billed dinosaurs and their early relatives (hadrosaurs, trachodon and iguanodon)

extinct terrestrial reptiles: theropods (carnivorous); sauropods (herbivorous)

gigantic herbivorous dinosaurs having huge bodies with long necks and small heads: Prosauropoda and Sauropoda (apatosaurus, diplodocus and titanosaurs)

the earliest known dinosaurs

any of the sauropod dinosaurs

carnivorous saurischian dinosaurs with short forelimbs; Jurassic and Cretaceous

primitive saurischian dinosaurs

largest carnivorous land animals ever known

lightly built medium-size theropods

advanced theropods including oviraptorids and dromaeosaurs and possibly even modern birds

extinct mammal-like reptiles found inhabiting all continents from the mid Permian to late Triassic

extinct reptiles of the later Triassic period

edaphosaurus; dimetrodon

extinct flying reptiles: pterosaurs

extinct terrestrial reptiles having teeth set in sockets; of the late Permian to Triassic

extinct marine reptiles: ichthyosaurs

extinct marine reptiles: plesiosaurs; nothosaurs

any of the plesiosaurs

a suborder of Sauropterygia

snakes

harvestmen

true scorpions

false scorpions

whip scorpions

spiders

mites and ticks

small elongate centipedes living in soil and under stones and having more than 30 pairs of legs

sea spiders

horseshoe crabs and extinct forms

extinct aquatic arthropods of the Paleozoic

pheasants; turkeys; grouse; partridges; quails; chickens; brush turkeys; curassows; hoatzins

coextensive with the family Tinamidae

sand grouse; pigeons; doves; extinct dodos and solitaires

an order of birds including parrots and amazons and cockatoos and lorikeets and lories and macaws and parakeets

cuckoos; touracos; etc.

rollers; kingfishers; hornbills; hoopoes; motmots; bee eaters; todies

term used in some classifications as nearly equivalent to the order Coraciiformes

swifts; hummingbirds

goatsuckers; frogmouths; oilbirds

woodpeckers; jacamars; puffbirds; barbets; honey guides; toucans

trogons

ducks; geese; swans; screamers

used in some especially older classifications; coextensive with the family Anatidae

coextensive with the subclass Prototheria

coextensive with the subclass Metatheria

shrews; moles; hedgehogs; tenrecs

moles; hedgehogs; true shrews

elephant shrews; tree shrews

marine colonial hydrozoans

sea anemones

corals and sea anemones having eight branches

comprising the soft corals

red corals and sea fans

stony corals

ctenophores having two long pinnate tentacles

an order of Tentaculata

ctenophore having short tentacles; one family

ctenophore having tentacles only in the immature stage; body compressed vertically having two large oral lobes and four pointed processes

comprising numerous marine gastropod mollusks lacking a shell in the adult state and usually having a body like a slug

large order of gastropods usually breathing by means of a lung-like sac comprising most land snails and slugs and many freshwater snails

large order of gastropods comprising univalve mollusks that have a single gill resembling a comb

an order of Amphineura

clams

octopuses and paper nautilus

squids and cuttlefishes

order of extinct dibranchiate cephalopods related to the surviving spirulas

lobsters; crayfish; crabs; shrimps; prawns

an order of crustaceans (including true crabs) having a reduced abdomen folded against the ventral surface

lobsters; crabs

shrimp; prawns; etc.

in former classifications a division of Malacostraca; superseded by the orders Mysidacea and Euphausiacea

small commonly luminescent crustaceans; important element of marine plankton: krill

opossum shrimp

mantis shrimps

woodlice

small flat-bodied semiterrestrial crustaceans: whale lice; sand-hoppers; skeleton shrimp

small aquatic crustaceans lacking a carapace: fairy shrimps; brine shrimps

small freshwater crustaceans with a shield-shaped carapace

copepods with suctorial mouthparts; parasitic on fishes

order of chiefly tropical marsh-dwelling fish-eating wading birds with long legs and bills and (except for flamingos) unwebbed feet: herons; storks; spoonbills; flamingos; ibises

inland marsh-dwelling birds with long legs and necks and bills that wade in water in search of food: cranes; rails; bustards

terrestrial game birds of the Old World and Australia: bustards

large diverse order of aquatic birds found along seacoasts and inland waters: shorebirds and coastal diving birds; most feed on anima life

shorebirds: plovers; sandpipers; avocets; phalaropes; coursers; stone curlews

term used in some classifications for migratory shorebirds; coextensive with the Charadrii

gulls; terns; jaegers; skimmers

large aquatic birds: loons and some extinct forms

grebes

pelicans; frigate birds; gannets; cormorants

penguins

petrels; albatrosses; shearwaters; diving petrels

an order of Eutheria

baleen whales: right whales; rorquals; blue whales; humpbacks

toothed whales: dolphins; porpoises; sperm whales; beaked whales

an animal order including: manatees; dugongs; Steller's sea cow

cats; lions; tigers; panthers; dogs; wolves; jackals; bears; raccoons; skunks; and members of the suborder Pinnipedia

seals; sea lions; walruses

an order of Eutheria

an old order dating to early Eocene: bats: suborder Megachiroptera (fruit bats); suborder Microchiroptera (insectivorous bats)

fruit bats

most of the bats in the world; all bats except fruit bats insectivorous bats

an order of insect identified in 2002 in a 45 million year old piece of amber from the Baltic region

an order of carnivorous insects usually having long membranous wings and long beaklike heads with chewing mouths at the tip

minute wingless arthropods: springtails

minute wingless arthropods: telsontails

beetles

web spinners

sucking lice

biting lice

fleas

a large order of insects having a single pair of wings and sucking or piercing mouths; includes true flies and mosquitoes and gnats and crane flies

mosquitoes; fungus gnats; crane flies; gnats; sand flies

an order of insects including: bees; wasps; ants; ichneumons; sawflies; gall wasps; etc.

order of social insects that live in colonies, including: termites; often placed in subclass Exopterygota

grasshoppers and locusts; crickets

in some classifications considered a suborder of Orthoptera: stick insects; leaf insects

in some classifications replaced by the orders (here suborders) Blattodea (cockroaches) and Manteodea (mantids); in former classifications often subsumed under a much broader order Orthoptera

cockroaches; in some classifications considered an order

mantises; in former classifications considered a suborder of Orthoptera

plant bugs; bedbugs; some true bugs; also includes suborders Heteroptera (true bugs) and Homoptera (e.g., aphids, plant lice and cicadas)

true bugs

plant lice (aphids); whiteflies; cicadas; leafhoppers; plant hoppers; scale insects and mealybugs; spittle insects

an order of insects: includes booklice and bark-lice

mayflies

stoneflies

an order of insects including: lacewings; antlions; dobsonflies; alderflies; fish flies; mantispids; spongeflies

in some classifications considered a separate order: alderflies; dobsonflies; snake flies

dragonflies and damselflies

dragonflies

damselflies

an order of insects consisting of caddis flies

firebrats; silverfish; machilids

thrips

earwigs and a few related forms

moths and butterflies

flat sea urchins

heart-shaped sea urchins

rabbits; hares; pikas; formerly considered the suborder Duplicidentata of the order Rodentia

small gnawing animals: porcupines; rats; mice; squirrels; marmots; beavers; gophers; voles; hamsters; guinea pigs; agoutis

true rats and mice and related rodents

an order of rodents including: porcupines; guinea pigs; chinchillas; etc.

large more or less primitive rodents: squirrels; marmots; gophers; beavers; etc.

small order of primitive ungulates of the Paleocene and Eocene

hyraxes and some extinct animals

nonruminant ungulates: horses; tapirs; rhinoceros; extinct forms

an order of hooved mammals of the subclass Eutheria (including pigs and peccaries and hippopotami and members of the suborder Ruminantia) having an even number of functional toes

cattle; bison; sheep; goats; antelopes; deer; chevrotains; giraffes; camels

order of mammals having few or no teeth including: New World anteaters; sloths; armadillos

armadillos; American anteaters; sloths

pangolins; in some former classifications included in the order Edentata

an animal order including lemurs and tarsiers and monkeys and apes and human beings

monkeys; apes; hominids

a small order comprising only the tree shrews: in some classifications tree shrews are considered either primates (and included in the suborder Prosimii) or true insectivores (and included in the order Insectivora)

not used in all classifications; in some classifications considered coextensive with the Lemuroidea; in others includes both Lemuroidea and Tarsioidea

Lemuridae; Lorisidae; Daubentoniidae; Indriidae; used in some classifications instead of Prosimii; in others considered a subdivision of Prosimii

in some classifications either coextensive with the Lemuroidea or comprising the true lemurs

in some classifications assigned to the suborder Prosimii

flying lemurs

an order of animals including elephants and mammoths

an order of fish belonging to the superorder Malacopterygii including catfishes

cods, haddocks, grenadiers; in some classifications considered equivalent to the order Anacanthini

at least partially equivalent to the order Gadiformes in some classifications

elongate fishes with pelvic fins and girdle absent or reduced

most primitive teleost fishes; all are soft-finned: salmon; trout; herring; shad; sardines; anchovies; whitefish; smelts; tarpon

teleost fish with bony tongues

anglers and batfishes; spiny-finned marine fishes having pectoral fins at the ends of armlike processes and a long movable spine on the dorsal fin to lure prey to the large mouth

order of fishes having spineless fins; needlefishes; sauries; flying fishes; halfbeaks

teleost fishes having fins with sharp bony rays

one of the largest natural groups of fishes of both marine and fresh water: true perches; basses; tuna

in some classifications nearly or exactly equivalent to the Perciformes which are considered a suborder

small order of fishes comprising the remoras

fishes distinguished by abdominal pelvic fins: families Mugilidae; Atherinidae; Sphyraenidae

blennies; butterfishes; gunnels

mackerels; tunas; albacores; bonitos; swordfishes; sailfishes

a group of mostly extinct primitive bony fishes characterized by armor-like bony scales

scorpionfishes; sculpins; gurnards; greenlings; flying gurnards

mail-cheeked fishes: scorpionfishes; gurnards

boxfishes; filefishes; globefishes; ocean sunfishes; triggerfishes; puffers

flatfishes: halibut; sole; flounder; plaice; turbot; tonguefishes

comprising solely the aye-aye