Ancient critter could be the granddaddy of shellfish

January 17th, 2013 in Other Sciences / Archaeology & Fossils
L-R: A Cotyledion tylodes fossil with U-shaped gut, an interpretative drawing, and an artistic reconstruction are pictured in a graphic released on January 17, 2013, by the scientific magazine "Nature". The marine creature, which lived 500 million years ago at a time of explosive growth in Earth's biodiversity, could be a forerunner of worms and molluscs, a study published on Thursday said.


L-R: A Cotyledion tylodes fossil with U-shaped gut, an interpretative drawing, and an artistic reconstruction are pictured in a graphic released on January 17, 2013, by the scientific magazine "Nature". The marine creature, which lived 500 million years ago at a time of explosive growth in Earth's biodiversity, could be a forerunner of worms and molluscs, a study published on Thursday said.

A weird marine creature that lived 500 million years ago at a time of explosive growth in Earth's biodiversity could be a forerunner of worms and molluscs, a study published on Thursday said.

Palaeontologists in China and Europe have taken a second look at fossils of a species called Cotyledion tylodes—a small animal that, when it was identified in 1999, was at first thought to be a cnidarian, or part of a group of -like species.

C. tylodes had a goblet-shaped body between eight and 56 millimetres (0.3 to 2.2 inches) long, with a cup-shaped upper part and lower cylindrical stalk.

On the upper part, the creature's mouth lay adjacent to its anus, with the two organs connected by a U-shaped gut and encircled by a "crown" of foldable tentacles, the scientists found.

The peculiar anatomy means that C. tylodes is most probably an entoproct, meaning an organism that strains to filter out suspended .

If so, its place in the family tree is wrong, says the study. It is likely to be a primitive lophotrochozoan, a branch that today includes worms and shellfish.

The study appears in the Scientific Reports.

(c) 2013 AFP

"Ancient critter could be the granddaddy of shellfish." January 17th, 2013. http://phys.org/news/2013-01-ancient-critter-granddaddy-shellfish.html