Eel-Like Creature’s Fossil May Be Oldest in ‘Chordate’ Group

NEW YORK — Scientists have found what might be the oldest known member of the evolutionary group that includes creatures with backbones.

The previously unknown eel-like creature, less than an inch long, lived about 535 million years ago in what is now central China. The fossil is reported in the Nov. 14 issue of the journal Nature.

It appears to be the oldest known “chordate” by about 10 million years, said study co-author Simon Conway Morris of Cambridge University. Chordates include backboned animals and some other species.

A previously discovered fossil from another creature of the same age had been designated a chordate, but that interpretation has been questioned, Morris said.

The new fossil shows what appear to be gill slits, but the creature did not have a backbone or fins, Morris said. The fossil does show the apparent remains of a notochord, a rod running along the body that is thought to be the precursor of a backbone, he said.