The Echinoid Directory

Family Somaliasteridae Wagner & Durham, 1966, p. U541

Diagnosis

 Hemiasterine spatangoids with:

  • ovate outline and gibbous profile;
  • plastron protamphisternous, with plates 5.a.2 and 5.b.2 enlarged but unequal and with markedly oblique median suture. Labral plate contacting only plate 5.b.2 (usually disjunct);
  • episternal plates biserially offset;
  • petals long and straight; weakly sunken to almost flush;
  • apical disc variable - ethmolytic or ethmophract;
  • peripetalous fasciole present.
Range
Upper Cretaceous (Campanian) to Palaeocene (Thanetian); Middle East and East Africa.