The Echinoid Directory

Sandiegoaster Sanchez Roig, 1952, p.12

Diagnostic Features	Test ovate without anterior sulcus. Apical disc ethmolytic, with 4 gonopores; positioned well anterior of centre. Madreporic plate projecting far to rear of posterior ocular plates. Anterior ambulacrum narrow and flush; pore-pairs small, simple isopores. Other ambulacra petaloid and depressed, the anterior pair almost at 180 degrees. Petals sunken and straight-sided; closed distally. Posterior petals diverging slightly distally. Columns of pore-pairs in petals very close, leaving almost no perradial space. Periproct large; on short and undercut posterior face. Peristome wider than long; kidney-shaped. Plastron plating uncertain, but sternal plates relatively wide and well-developed so that plastron appears strongly bowed No large primary tubercles differentiated. Well-developed peripetalous and subanal fascioles. Subanal fasciole bilobed.
Distribution	Mid to Late Eocene, Cuba.
Name gender	masculine
Type	Sandiegoaster durhami, Sanchez Roig, 1952, p. 12, by original designation.
Species Included	Only the type species.
Classification and/or Status	Spatangoida, Micrasterina, Brissidae. Subjective junior synonym of Brissus Gray, 1825.
Remarks	The holotype of this species was redescribed and figured by Kier (1984). There are no differences of substance between this taxon and Brissus, although the position of the periproct is more inframarginal. Kier, P.M. 1984. Fossil spatangoid echinoids of Cuba. Smithsonian Contributions to Paleobiology 55, 1-336.