The Echinoid Directory

Family Polycidaridae Vadet, 1988, p. 103

[=Nenoticidaridae Vadet, 1988, p. 107; =Anisocidaridae Vadet, 1999]


 Cidaroids with:

  • Coronal plating more or less tesselate (adapical interambulacral - ambulacral sutures may be somewhat imbricate in basal taxa).
  • Primary interambulacral tubercles crenulate and perforate, with relatively small mamelon; scrobicular tubercles poorly differentiated; extrascrobicular tuberculation heterogeneous.
  • Ambulacral plating pseudocompound, with enlarged tubercles on every second or third plate, at least adorally.
  • Primary spines slender and thorned; secondary spines not flattened or adpressed.
Upper Triassic (Carnian) to Lower Cretaceous (Neocomian); Europe, North Africa, probably wider.
Classification and/or Status Cidaroida stem group

Possibly paraphyletic.

The retention of pseudocompound ambulacra, with every second or third plate enlarged to house a larger primary tubercle, is a primitive trait held over from miocidarids and also seen in Rhabdocidaridae and Diplocidaridae. It is unlikely that this will prove to be a monophyletic grouping. The spines are long and slender and the mamelons correspondingly smaller in all but Paracidaris.

Almost certainly a paraphyletic grade by exclusion of Diplocidaridae and Histocidaridae.

Vadet, A. 1988. Revision des "Cidaris" d'Oxfordien et du Kimmeridgien Europeens. Memoires de la Societe academique du Boulonnais 4, 1-148, pls 1-25.