Perischoechinoidea

Perischoechinoidea

[pə¦ris·kō‚ek·ə′nȯid·ē·ə]
(invertebrate zoology)
A subclass of principally extinct echinoderms belonging to the Echinoidea and lacking stability in the number of columns of plates that make up the ambulacra and interambulacra.
References in periodicals archive ?
The Cidaroida, the only extant order of the subclass Perischoechinoidea, is the lineage most divergent from all other echinoids.
Echinoidea: SCB, in the form of short rods, were found in Goniocidaris umbraculum, a representative of the primitive subclass Perischoechinoidea.