Friday, January 22, 2010

Animal taxonomy

A reasonably current synopsis:

OUTLINE of ANIMAL TAXONOMY (incomplete! Only largest groups shown)
The “big nine” major phyla are in boldface.
All named taxa are believed to be monophyletic unless indicated.
Non-monophyletic traditional taxa are in “quotation marks”
Bilaterians are coelomates unless indicated otherwise.

Kingdom Animalia (= Metazoa)
[choanoflagellates: sister group of metazoans; sometimes included in Kingdom]
I. Parazoa: Porifera (sponges; para-/polyphyletic?)
    A. glass sponges
    B. demosponges
    C. calcareans

II. Eumetazoa
    ?:  Placozoa
    A. Radiata (para-/polyphyletic?)
        1. Ctenophora (comb jellies)
        2. Cnidaria
            a. hydrozoans (Hydra, hydroids, siphonophores)
            b. scyphozoans (jellyfish)
            c. cubozoans (sea wasps)
            d. anthozoans (anemones, corals)

    B. Bilateria
        Protostomes (=1+2 below)
        1. Lophotrochozoa
            a. “Platyhelminthes” (=flatworms; acoelomate; monophyletic if acoelomorphs excluded)
                i. free-living flatworms (paraphyletic?)
                ii. "flukes" (probably paraphyletic)
                iii. tapeworms
            b. Rotifers (pseudocoelomate)
            c. “Lophophorate” phyla (bryozoans, brachiopods, phoronids; prob. polyphyletic)
          Spiralia (d & e below; para-/polyphyletic?)
            d. Annelida
                i. polychaetes (inc. motile polychaetes, tubeworms; paraphyletic?)
                ii. vestimentiferans
                iii. oligochaetes (earthworms & relatives; paraphyletic?)
                iv. leeches (sometimes lumped with oligochaetes as “clitellates”)
            e Mollusca
                i. chitons
                ii. bivalves (clams, mussels, oysters)
                iii. gastropods (snails, slugs)
                iv. cephalopods (squid, octopus, cuttlefish, nautilus)

        2. Ecdysozoans
            a. Nematoda (=roundworms; pseudocoelomate)
            b. i. onychophorans
                ii. tardigrades
            c. Arthropoda (sometimes considered a superphylum)
                i. trilobites (extinct)
                ii. chelicerates (mostly arachnids [spiders, scorpions, ticks, mites])
                iii. myriapods    (centipedes, millipedes)
                iv. "crustaceans" (decapods, copepods, barnacles, etc.; probably paraphyletic)
                v. hexapods (mostly insects [dragonflies, beetles, ants/bees/wasps, roaches, flies, fleas, butterflies/moths, mantids, etc. etc. etc.])

      3. Deuterostomes
            a. Echinodermata
                i. crinoids (seas lillies, feather stars)
                ii. sea urchins & relatives (sand dollars etc.)
                iii. brittle stars
                iv. sea stars
                v. sea cucumbers
            b. Chordata
                i. cephalochordates (lancelets)
                ii. urochordates (tunicates, salps, larvaceans)
                iii. Vertebrates
                    a. jawless fishes (hagfish, lampreys; paraphyletic)
                    b. cartilaginous fishes (sharks, rays, chimaeras)
                bony fishes (c-e below; paraphyletic)
                    c. ray-finned fishes (extremely diverse!)
                    d. coelacanths
                    e. lungfishes
                tetrapods (f-i below)
                    f. amphibians (frogs, salamanders, caecilians)
                amniotes (g-i below)
                    g. mammals (monotremes, marsupials, eutherians)
                    h. “reptiles” (turtles, crocodilians, lepidosaurs, many extinct clades; paraphyletic!)
                    i. birds

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