The Echinoid Directory

Contributed by Andrew Smith, December 2006

Ancyclocidaris Miller, 1929, p. 334

Diagnostic Features
  • Test depressed with rounded ambitus
  • Apical disc plating missing
  • Ambulacra with simple plating at the ambitus and aborally, with pore-pairs uniserially arranged
  • Interambulacral plates wide and geniculate.
Distribution Sundance Formation, Upper Jurassic, Wyoming, USA
Name gender feminine
Type Type species Ancyclocidaris spenceri Miller, p. 335, by monotypy.

Only known specimen stated to be in Tulane University Paleontological collections.
Species Included Only the type species.
Classification and/or Status Indeterminate.
Remarks The unique specimen is preserved in crystalline calcite and shows no surface details. 

Miller, A. K. 1929. Ancyclocidaris, a new echinoid genus from the Sundance of West-Central Wyoming. American Journal of Science (5) 18: 334-336.