The Echinoid Directory

Contributed by Andrew Smith, December 2010

Order Aspidodiadematoida Kroh & Smith, 2010, p. 170

Diagnosis Acroechinoidea with:
  • subglobular test
  • apical disc monocyclic with ocular and genital plates similar in size and set in a membranous periproct; plates not attached to the corona
  • ambulacral plating acrosaleniid in triads at least adorally and with some elements united by tubercle overgrowth
  • interambulacral plates with single large tubercle; perforate and crenulate
  • sphaeridia present in shallow pits on every third element from peristome to apex
  • peristome large; buccal notches shallow and rounded
  • spines with central lumen crossed by partitions and fine needle-like pillars.
Range Lower Jurassic to Recent
Type Aspidodiadema
Species Included Contains only the Family Aspidodiadematidae
Classification and/or Status Euechinoidea, Acroechinoidea
Remarks Kroh, A. & Smith, A. B. 2010. The phylogeny and classification of post-Palaeozoic echinoids. Journal of Systematic Palaeontology 8, 147-212.