Animal Diversity 3Deuterostomes: Echinodermata and Chordata

Echinodermata & Chordata

Echinodermata “Spiny skin”

• Endoskeleton of spiny plates

• Marine animals (no freshwater or terrestrial species)

• Adults = radial; larvae = bilateral

• Water vascular system (used for feeding, gas exchange, and locomotion)

• Canals end in “tube feet”; opening = madreporite

Bilateral Larva

Chordata

•Pharyngeal slits/pouches

•Dorsal nerve cord

•Notochord

•Post-anal tail

Pharyngeal slits

Dorsal (hollow) nerve cord

Nerve cord

Notochord

(versus solid, ventral nerve cord)

Notochord

Nerve cord

Notochord

Flexible rod that supports the nerve cord(becomes intervertebral discs in between vertebrae in humans.)

Post anal tail

(body extends past the anus...)

Chordata

•Pharyngeal slits/pouches

•Dorsal nerve cord

•Notochord

•Post-anal tail

Subphyla

Tunicata(once called Urochordata)Craniata

Cephalochordata

CephalochordataExample: lancelets

Tunicata

Craniata (Vertebrata)

Specimens today•Lancelet (one per table)

•Lamprey

•Sea cucumber

•Sea Urchin

•Sea Star