Chordate and Invertebrate Classification Overview

Urochordata (tunicates)

Adhesive organs; possess male & female organs.

Cephalochordate (lancelets)

Filter feeder; buccal cirri; wheel organ.

Agnatha

Cartilage skeleton; no scales, no paired fins; eel-like.

Chondrichthyes

Jaws, cartilage skeletons; scales; paired fins/nostrils; sharks, rays.

Osteichthyes

Bony skeleton; operculum; swim bladder; ray-finned or lobe-finned.

Amphibia

Lay eggs in water; skin needs to be wet.

Reptilia

Amniotic eggs; live on land.

Aves

Feathers, beaks; lightweight skeleton; hard-shelled amniotic eggs.

Mammalia

Hair, mammary glands; endothermic.

Porifera

Aquatic; pore-bearing; sessile as adults; hard spicules or spongin fibers; no true tissues.

Cnidaria

Tentacles with nematocysts; polyp & medusa forms.

Mollusca

Mantle; muscular foot.

Platyhelminthes

Dorso-ventrally flattened worms; cephalization; 'pancake!'.

Annelida

Segmented, ring-like.

Nematoda

Smooth, round-bodied worms with tapered ends.

Arthropoda

Joint appendages; chitinous exoskeleton.

Echinodermata

Spiny skin with exoskeleton; water vascular system.