The Echinoid Directory

Anabrissus Mortensen, 1950, p. 161

Diagnostic Features	Test ovate with no anterior sulcus; posterior face truncate. Apical disc ethmolytic with three gonopores. Anterior ambulacrum narrow and flush; individual plates taller than wide. Pore-pairs rudimentary. Petals short and more or less flush; extending only about half-way to the ambitus. The anterior pair set at almost 180 degrees. Perradial zone between columns of pore-pairs in petals extremely narrow. Peristome D-shaped and downward facing. Labral plate short and wide. Plastronal area wide and ovate in outline; composed of sternal and episternal plates. Posterior ambulacra on oral surface relatively narrow and bowed. Periproct on posterior truncate face; well below mid-height in posterior view. Bilobed subanal fasciole present. Peripetalous fasciole present but rudimentary.
Distribution	Recent, tropical Atlantic.
Name gender	masculine
Type	Brissus damesi Agassiz, 1881, p. 197, by original designation.
Species Included	B.damesi Agassiz, 1881; Recent, Brazil.
Classification and/or Status	Spatangoida, Micrasterina, Brissidae. Monotypic.
Remarks	Differs from Brissus in having much smaller, less well-developed petals which are more or less flush rather than depressed. It also has three rather than four gonopores. In test architecture and other respects, the two are very similar. Mortensen, T. 1951. A monograph on the Echinoidea. V, Spatangoida 2. C.A. Reitzel, Copenhagen.