Ctenocystoidea: New Class of Primitive Echinoderms

Science  19 Dec 1969:
Vol. 166, Issue 3912, pp. 1512-1514
DOI: 10.1126/science.166.3912.1512


The oldest known "carpoids" of the echinoderm subphylum Homalozoa have been discovered in lower Middle Cambrian rocks of northern Utah. They were free-living benthonic animals characterized by a unique ctenoid feeding apparatus and flattened flexible theca with near bilateral symmetry. A new class, Ctenocystoidea, is proposed to include the new genus and new species, Ctenocystis utahensis.