The Echinoid Directory

• Test ovate without anterior sulcus; posterior face truncate. Test rounded in profile with keeled sternum (possibly a preservational artefact).
• Apical disc ethmolytic with four gonopores; anterior of centre.
• Anterior ambulacrum flush aborally; narrow; pore-pairs rudimentary.
• Paired ambulacra petaloid aborally; very weakly sunken. Anterior petals widely divergent, almost at 180 degrees; pore-pairs slightly flexed distally; pore-pairs in the anterior column less well developed compared to those in the posterior column.
• Posterior petals similar but shorter; both columns equally developed; with little perradial space between columns.
• Peristome D-shaped and facing obliquely downwards; labral plate slightly overarching.
• Plastron plating unknown.
• Periproct on posterior truncate face; depressed.
• Peripetalous fasciole indented behind anterior paired petals and crossing ambulacra about 3 plates below the end of the petals; inframarginal at anterior. Lateroanal fasciole not reported.

• Eocene, Italy.

Parabrissus pseudoprenaster Bittner, 1880, p. 59; by original designation.

• Only the type species.

Spatangoida, Paleopneustina, Prenasteridae.

Monotypic; possible synonym of Prenaster Desor, 1853.

Distinguished from Prenaster only in having less well developed pore-pairs in the anterior column of the anterior ambulacrum. Distinguished from Agassizia by the anterior apical disc and widely divergent anterior petals. There is no mention of a lateroanal fasciole in Bittner's description, but it is not clear whether it is truly absent, or just missed through poor preservation.

Bittner, A. 1880. Beitrage zur Lenntuiss altertiarer Echiniden der Sudalpen. Beitrage zur Palaeontologie von Oestereich Ungarn herausgegeben von edm v. Mojosisovics u. m. Neumayer; I, 43-71, pl. V-XIII (I-VIII).