The Echinoid Directory

Plagiopneustes Fourtau, 1905, p. 609

Diagnostic Features	Test ovate with shallow anterior sulcus. Test rather inflated in profile. Apical disc ethmophract with four gonopores; anterior of centre. Anterior ambulacrum forming shallow groove from apex to peristome. Pore-pairs small and undifferentiated. Paired ambulacra petaloid; petals long, parallel-sided and extending almost to the ambitus. Open distally. Peristome D-shaped and only slightly inclined towards anterior. Plastron plating unrecorded; fully tuberculate with labrum apparently relatively broad. Periproct on posterior truncate face. Subanal and peripetalous fascioles present. Peripetalous fasciole narrow; not indented behind anterior paired petals. Aboral tuberculation heterogeneous; slightly coarser inside peripetalous fasciole.
Distribution	Eocene, Egypt.
Name gender	feminine
Type	Macropneustes crassus Agassiz, 1847, p. 115, by orginal designation.
Species Included	M. crassus Agassiz, 1847; Middle Eocene, Egypt.
Classification and/or Status	Spatangoida, Micrasterina, Macropneustidae. Subjective junior synonym of Macropneustes Agassiz, 1847.
Remarks	Differs from Megapneustes in having petals long and parallel and slightly depressed, without tubercles perradially. Fourtau, R. 1905. Compte Rendue Assoc. France 33, p. 609.