The Echinoid Directory

Stegaster Pomel, 1883, p. 48

[=Rispolia Lambert, 1917, p. 27, type species Nucleolites subtrigonatus Catullo, 1827]

Diagnostic Features	Test very thick; cordate with pronounced anterior sulcus. Lower surface carinate. Subconical in profile. Apical disc subcentral; hoilasterid, with small gonopores. Paired ambulacra non-petaloid. Frontal groove well-defined from ambitus to peristome. Peristome small and circular, facing towards anterior. Plastron plating meridosternous, with elongate labral plate followed by a single sternal plate, then offset episternal plates . Enlarged primary tubercles absent. ?No fascioles.
Distribution	Upper Cretaceous (Senonian) of Europe.
Name gender	masculine
Type	Cardiaster gillieroni de Loriol, 1873, p. 4, by original designation.
Species Included	Pomel (1883) included various taxa in his genus Stegaster, including Nucleolites subtrigonatus Catullo, type species of Rispolia and Cardiaster pygmaeus Forbes, a true Cardiaster.
Classification and/or Status	Holasteroida, Meridosternata, Stegasteridae.
Remarks	The holotype of the type species is in the de Loriol collection and has been studied. It is illustrated here. From this it would appear to be indistinguishable from Rispolia. The individual figured is only 18 mm in length and may be a juvenile.