The Echinoid Directory

Family Histocidaridae Lambert, 1900, p. 49

[= Histocidarina Mortensen, 1928, p. 69]

Diagnosis	Cidarids with: test with tesselate sutures primary tubercles perforate and strongly crenulate primary tubercles confluent adorally and ambitally; scrobicular tubercles differentiated; extrascrobicular tuberculation heterogeneous ambulacra straight primary spines long, cylindrical with simple unbranched cortical hairs secondary spines slender, simple and unflattened.
Range	Upper Triassic (Rhaetic) to Recent; widespread.
Species Included	Only the genus Histocidaris is included.
Classification and/or Status	Cidaroida, Histocidaridea
Remarks	Distinguished from Rhabdocidaridae by its non-conjugate pore-pairs and from micodarids by its non-denticulate and more or less firmly tesselate ambulacral-interambulacral plate sutures. It differs from Cidaridae by its strongly crenulate tubercles and from Psychocidaridae by its small and clearly perforate mamelons and long cylindrical spines. Lambert, J. 1900. Étude sur quelques Échinides de l'Infra-Lias et du Lias. Bulletin de la Société des Sciences Historiques et Naturelles de l'Yonne 52 (1899)(2), 3-57.