The Echinoid Directory

Family Rotulidae Gray, 1855, p. 65

Diagnosis

 Laganiformes with:

  • simple to complex internal buttressing present;
  • periproct adoral;
  • interambulacral zones terminating adapically in a series of small, uniserial plates;
  • basicoronal circlet with first interambulacral plates tiny and internal so that the first circle of plates around the peristome when viewed externally is composed of 10 ambulacral and 10 interambulacral plates;
  • food grooves present and branching, but without perradial ridge projecting into peristome;
  • apical disc pentagonal, with points of pentagon radial;
  • miliary spines ending in a crown, without glandular sac.
Range
 Miocene to Recent; West Africa.