The Echinoid Directory

Family Rhabdocidaridae Lambert, 1900, p. 49


 Cidaroids with:

  • Rigidly sutured corona of relatively thin plates; ambulacral plates rather firmly bound to interambulacral plates.
  • Apical disc dicyclic.
  • Interambulacral plates with single large primary tubercle that is perforate and strongly crenulate; areoles shallow; extrascrobicular tuberculation strongly heterogeneous.
  • Ambulacral plating simple throughout; pore-pairs strongly conjugate.
  • Spines long and relatively stout with cortex; often spatulate or facetted with the two sides differentiated; usually coarsely thorned.
Lower Jurassic (Pliensbachian) to Eocene, ? Miocene; widespread.
Distinguished from Cidaridae by its strongly crenulate tubercles and from Histocidaridae by its strongly conjugate pore-pairs.

Lambert, J. 1900. Etude sur quelques echinides de l'Infra-Lias et du Lias. Bulletin de la Societe des Sciences naturelles et historiques de l'Yonne 52 [for 1899], 3-57.