The Echinoid Directory

Contributed by Andrew Smith, August 2011

Hypopygurus Gauthier, 1889, p. 37

Diagnostic Features	Test medium to large, elongate with pointed posterior; adoral surface concave Apical disc anterior, tetrabasal with 4 gonopores; Petals broad, open, with straight poriferous zones, posterior petals longer than the others; pore-pairs conjugate with outer pore slit-like All ambulacral plates double-pored Periproct inframarginal, longitudinally elongate Peristome anterior, pentagonal Bourrelets well developed, inflated, phyllodes broadened with pore-pairs in two series in each half ambulacrum; single buccal pores present
Distribution	Cenomanian, Upper Cretaceous, Tunisia
Name gender	masculine
Type	Hypopygurus gaudryi Gauthier, 1889, p. 38 by monotypy
Species Included	Only the type species.
Classification and/or Status	Irregularia, Echinoneoida, Pygaulidae Monotypic.
Remarks	Kier correctly associated this with Pygorhynchus distinguishing it on the presence of buccal pores. Gauthier, V. 1889. Description des echinides fossiles recueillis en 1885 et 1886 dans la region sud des hauts plateaux de la Tunisia par M. Philippe Thomas. 116 pp., 6 pls. Kier, P. M. 1962. Revision of the cassiduloid echinoids. Smithsonian Miscellaneous Collections 144(3), 262 pp., 44 pls.