The Echinoid Directory

• Test strongly cordate in outline with deep frontal groove. Subconical in profile and flat-based.
• Thick-shelled.
• Apical disc subcentral with a gonopore in each genital plate and two or more gonopores in ocular plates II and IV.
• Frontal groove weak adapically but becoming very deep by the ambitus and continuing to the peristome as a sharply defined channel.
• Peristome circular and facing forwards into frontal groove.
• Paired ambulacra sub-petaloid; pore-pairs in posterior column better developed than those in the anterior column.
• Periproct posterior, with a bilobed subanal projection.
• Plastron plating meridosternous - labral plate followed by single large and symmetrical sternal plate; episternals paired and almost symmetric. No rostral plate.
• Plastron plating continuous in posterior interambulacrum, but disjunct in paired lateral interambulacra, with first interambulacral plate separated from succeeding interambulacral plates.
• Ring of coarse primary tubercles in supra-ambital region around the most of the test. Otherwise tuberculation fine and uniform.
• Marginal fasciole present.

Upper Cretaceous (?Cenomanian, Campanian - Maastrichtian); North Africa, Madagascar, Spain, France, Denmark, Caucasus, Ukraine, Dagestan.

Guettaria angladei Gauthier, 1888, p. 52, by original designation.

• G. rocardi Cotteau, 1889; Campanian-Maastrichtian, North Africa, Madagascar, Ukraine and Kopet Dag.
• G. fecunda Schulz, 1983; Early Maastrichtian, Germany.
• G. angladei Gauthier, 1887; Campanian, Algeria.
• G. fourmarieri (Lambert, 1931); Upper Campanian, Turkey, Tunisia.
• ?G. pustulifer Peron & Gauthier, 1878; Cenomanian, Algeria.

Holasteroida, Meridosternata, Stegasterina, Stegasteridae.

Presumed monophyletic.

Differs from Seunaster in having a deep and sharply defined frontal groove, a ring of supra-ambital primary tubercles and a marginal fasciole. Differs from Tholaster in lacking strong primary tubercles periapically and in having well-developed pore-pairs adapically. Further distinguished from both by having auxilliary gonopores in the ocular plates. The only other stegasterine with auxillary gonopores in ocular plates is Lampadaster, which differs from Guettaria in having fine, uniform aboral tuberculation only.

Gauthier, V. 1888. C. R. Assoc. France, 1887 (2), p. 528.

Schulz, M. G. 1983. Die Echinodermen der Inoceramen-Mergel (Buntmergelserie, Ultrahelvetikum, Unter-Maastricht) des Moos-Grabens SE Siegsdorf (Oberbayern). Zitteliana 10, 715-723.

Smith, A. B. & Jeffery, C. H. 2000. Maastrichtian and Palaeocene echinoids: a key to world faunas. Special Papers in Palaeontology 63, 1-404.