The Echinoid Directory

Wrigthia Pomel, 1869, p. 46

[=Wrightella Pomel, 1883, p. 115 (objective)]

Diagnostic Features
  • Based on a fragment of test only; shape unknown, plating apparently imbricate.
  • Ambulacra narrow, straight, quadriserial, with inner series of plates small and occluded from adradial suture; pore-pairs shown as forming four columns.
  • Interambulacral plates small and irregularly polygonal; reconstructed as forming columns and rows, but this is purely hypothetical - plates are possibly not strictly hexagonal as shown.
Distribution
Silurian, UK.
Name gender feminine
Type
Palaechinus phillipsiae Forbes, 1848, by original designation.
Species Included
  • Only the type species.
Classification and/or Status

Stem group Echinoidea; Echinocystitidae.

Monotypic; possible synonym of Echinocystites

Remarks

The reconstruction of plating given by Forbes is highly speculative. The ambulacral plating suggests affinities with Echinocystitidae and it is possible that this taxon is congeneric with Echinocystites. The material, however, is too poorly preserved to be sure and the name is best restricted to the type specimen and treated as a nomen dubium

Forbes, E. 1848. Figures and descriptions of British Organic Remains. Memoirs of the Geological Survey of Great Britain Dec. 2, plate 1.

Jackson, R. T. 1912. Phylogeny of the Echini, with a revision of Palaeozoic species Memoirs of the Boston Society of Natural History 7, 491 pp. 76 pls.

Pomel, N. A. 1869. Revue des Echinodermes et leur classification pour servir d'introduction a l'etude des fossiles. lxvii pp, Paris.