chordate

Animal belonging to the phylum Chordata, which includes vertebrates, sea squirts, amphioxi, and others. All these animals, at some stage of their lives, have a supporting rod of tissue (notochord or backbone) running down their bodies.

Chordates are divided into three major groups: tunicates, cephalochordates (see lancelet), and craniates (including all vertebrates).

A new chordate Yunnanozoon lividum, a cephalochordate, was found 1995 in Chengjiang, China. It is 525 million years old, and the first chordate recorded from the early Cambrian period.