The Echinoid Directory

Jacksonechinus Lambert, 1936, p. 39

Diagnostic Features
  • Test shape probably depressed, circular; plating rather thick and subtesselate.
  • Apical disc unknown; relatively small.
  • Ambulacra narrow adapically, expanded at ambitus and adorally; multiserial from close to apex to peristome (in six columns); the two central columns having tubercles which are mamelonate and perforate. Aboral plates small and with small, unspecialized pore-pair; adoral and ambital plates larger and dominated by large, subcircular pore-pair with prominent rim.
  • Interambulacral zones wider than ambulacral zones; composed of 4 or 5 columns of polygonal plates arranged in rows.
  • Subcentral primary tubercle present on outer series of interambulacral plates, plus smaller marginal tubercles; inner series of plates with only granules.
  • Lantern, peristome and spines unknown.
Distribution
Upper Carboniferous, Egypt.
Name gender masculine
Type
Jacksonechinus andrewi Lambert, 1936, p. 40, by original designation.
Species Included
  • Only the type species.
Classification and/or Status

Stem group Echinoidea; Proterocidaridae.

Monotypic; subjective junior synonym of Proterocidaris de Koninck, 1882.

Remarks

Kier in 1966, tentatively synonymized his genus with Proterocidaris.

Lambert, J. 1936. Sur quelques nouveaux echinides fossiles d'Egypt. Bulletin de l'Institute d'Egypte, 18, 39-43, 1 pl.

Kier, P. M. 1966. Noncidaroid Paleozoic echinoids. Pp. U298-312 in Moore, R. C. (ed.) Treatise on Invertebrate Paleontology. University of Kansas Press & Geological Society of America, Lawrence.