The Echinoid Directory

• Test ovate with rather shallow and wide anterior sulcus bordered by weak carinae aborally.
• Apical disc with four gonopores. Hydropores scattered over anterior genital and ocular plates; genital plate 2 and 1 abut, making ocular II exsert.
• Paired ambulacra rather strongly flexed and with columns of pore-pairs markedly unequal in width. Pore-pairs in posterior columns conjugate and elongate; those in the anterior column small and much less elongate, especially adapically.
• Frontal groove continuous from apex to peristome; mouth weakly inclined towards the anterior; partially covered by labral plate in oral view.
• Plastron plating protosternous with strongly V-shaped plates alternating.
• Periproct marginal, on vertical truncate face. Two weak subanal nodes.
• Aboral tuberculation fine and homogeneous.
• Marginal fasciole present at least posteriorly.

Upper Cretaceous (Santonian), North Africa (Algeria).

Holaster jullieni Peron & Gauthier, 1881, p. 53, by original designation.

• Only the type species.

Holasteroida, Hemipneustidae.

Subjective junior synonym of Hemipneustes Agassiz,1836.

Differs from Hemipneustes only in having a slightly shallower and wider anterior groove and in having ocular II exsert and not separating genital plates 1 and 2. Sister taxon to Medjesia.

The taxonomic status of this genus has been discussed by Jeffery (1997).

Jeffery, C. H. 1997. Revision of the echinoid Enallopneustes from the Upper Cretaceous of North Africa. Cretaceous Research 18, 237-248.

Pomel, A. 1883. Classification méthodique et genera des Échinides vivante et fossiles. Thèses présentées a la Faculté des Sciences de Paris pour obtenir le Grade de Docteur ès Sciences Naturelles, 503, 131 pp. Aldolphe Jourdan, Alger.