The Echinoid Directory

Porocidaris Desor, 1855, p. 46

[Parocidaris Nobre, 1909, p. 19 (misspelling) ]

Diagnostic Features
  • Test large and relatively thin-plated.
  • Apical disc unknown.
  • Interambulacra with some 8-10 plates in a column. Primary tubercles central; ovate, perforate, strongly crenulate. Areoles incised and confluent ambitally.
  • Scrobicular tubercles not really differentiated; extrascrobicular zones developed only on adradial and interradial margins and relatively uniform.
  • Ambulacra rather straight with pore-zones sunken. Pore-pairs conjugate, the two pores widely separated. perradial zone also broad, with horizontal row of small, separated tubercles to each plate.
  • Peristome unknown.
  • Primary spines short and blade-like with serrated margins and fine granular ornament. Collar long and distinctly granular.
Middle Eocene, North Africa, India and the Middle East.
Name gender feminine
Cidarites schmidelii Munster, 1843, p. ***, by subsequent designation of Lambert & Thiery, 1910, p. 108.
Species Included
  • Only the type species is based on reasonably complete test fragments (Lambert & Thiery 1914, p. 138, list 3 other species).
Classification and/or Status

Cidaroida; Rhabdocidaridae.


Highly distinctive rhabdocidarid because of the radial grooves that are so well developed around the outer part of its primary tubercle areoles.

Desor, E. 1855-1858. Synopsis des echinides fossiles. Reinwald, Paris. 490 pp., 44 pls. [part published April, 1855]

Lambert, J. & Thiery. P. 1909-1925. Classification raisonnees des echinides vivants et fossiles. Chaumont, Ferriere.