The Echinoid Directory

Allotoxaster Nisiyama, 1968, p. 181

Diagnostic Features	Test small, oval in outline with rounded margin; steeply rounded anterior and truncate posterior. Feeble frontal depression at ambitus. Oral surface weakly convex. Apical disc central; structure unknown but clearly compact. Ambulacrum all similar; subpetaloid; flush adapically; open distally. Petaloid zones open and ending gradually; weakly flexed. Peristome small, subcircular; facing obliquely towards shallow anterior furrow. Plastron plating unreported. Periproct small and towards the top of posterior truncate face. Tubercles and spines unknown.
Distribution	Japan. Originally listed as Cretaceous, but stated to be Upper Jurassic by Nisiyama (1968) - Jurassic age seems highly implausible.
Name gender	masculine
Type	Toxaster tosaensis de Loriol, 1902, p. 36, by original designation.
Species Included	Only the type species.
Classification and/or Status	Spatangoid indet. Monotypic; indeterminate.
Remarks	The type is based on a specimen that has lost the external surface of the test. de Loriol, P. 1902. Notes pour servir a l'etude des Echinodermes. Seconde Serie, fascicule 1. Bale & Geneve, Librairie Georg & Co. Nisiyama, S. 1968. The echinoid fauna from Japan and adjacent regions part II. Palaeontological Society of Japan Special Papers 13, 1-491, pls 1-30.