The Echinoid Directory

Taphraster Pomel, 1883, p. 46

Diagnostic Features
  • Test cordate in outline with deep frontal groove; flat-based with keeled plastron.
  • Apical disc subcentral; detailed structure unknown.
  • Frontal groove deepening to the ambitus and continuing to the peristome as a sharply defined channel.
  • Peristome ovate and facing downwards; closer to centre than anterior.
  • Paired ambulacra very slightly depressed throughout. Pore-pairs small and simple; non-petaloid.
  • Periproct on steeply sloping posterior face; visible from above. Subanal region projecting.
  • Plastron plating unknown.
  • Enlarged primary tubercles only bordering the frontal groove.
  • ?No fascioles.
Distribution
Lower Cretaceous (Neocomian); Switzerland.
Name gender masculine
Type
Holaster campicheanus (d'Orbigny, 1858, p. 79), by original designation.
Species Included
  • Only the type species.
Classification and/or Status

Holasteroida, ?basal stem group.

Monotypic.

Remarks
This singular holasteroid is too poorly known to be able to place with confidence. Distinguished from all other genera by having all five ambulacra slightly depressed on both oral and aboral surfaces. Ambulacra form indented zones at the ambitus in plan view. It is tentatively placed as a basal Holasteroida.

Pomel, A. 1883. Classification methodique et genera des echinides vivants et fossiles. Thesis presentees a la Faculte des Sciences de Paris 503. 132 pp. A. Jourdan, Alger.