Cothurnocystis

Cothurnocystis is a genus of small, enigmatic echinoderms that lived during the Ordovician. Individual animals had a flat, boot-shaped body and a thin, rod-shaped appendage that may be a stem, or analogous to a foot or a tail. Fossils of Cothurnocystis species have been found in Nevada, Scotland, Czech Republic, France and Morocco.

Taxonomy
The position of the Stylophora, of which Cothurnocystis is a prominent representative, has been in a state of flux. Some scientists claim to be able to see a structurally very basic notochord in the tail, and consequently consider the Stylophora to be a group of primitive chordates, calling them the "Calcichordata". Alternatively these animals are considered related to echinoderms, as the shell (or test) is similar in structure and composition to the tests of echinoderms. However, stylophoras are asymmetric organisms that lack either the radial symmetry typical of most echinoderms, or the bilateral symmetry of the chordates.

Etymology

 * C. americana refers to the continent where it was found.
 * C. curvata is named for the curved form of its theca.[2]
 * C. elizae honors of mrs. Robbert Gray, who collected the specimens the description of this species is based upon.