Distinguished from Lytechinus primarily on the larval stage morphology, In Cyrtechinus the larva lacks a basket structure, whereas this is always developed in Lytechinus. The primary test character differentiating the two is that Cyrtechinus is densely covered in tubercles throughout, whereas in Lytechinus there are adapical interradial naked zones. It differs from Nudechinus only in having a densely plated peristomial membrane. In other respects it is virtually indistinguishable, and Mortensen noted the close similarity of the two genera when erecting this taxon.
Mortensen, T. (1943) A monograph of the Echinoidea Part III.2, Camarodonta 1. C. A. Reitzel, Copenhagen.