The Echinoid Directory

Contributed by Philippe Nicolleau, April 2009

Smithiaster Barras 2007, p. 158

Diagnostic Features	Test ovate, no anterior sulcus. Ambitus rounded. Apical disc disjunct with posterior ocular plates only separated by a short distance from the remainder of the apical disc, but by a great distance from the periproct. Ambulacra all similar. Pore-pairs small, extending from the apex to the peristome. Peristome ovate transversally, anterior of centre. Periproct small, marginal or supra marginal. Tuberculation with fine scattered, crenulated and perforate tubercles, finely scrobiculated, set in groundmass of granules. Plastron plating protosternous
Distribution	Upper Jurassic (Callovian to Kimmeridgian), Europe, Morocco, Algeria.
Name gender	masculine
Type	Dysaster loryi Gras 1852, p. 49, by designation of Barras, 2007, p. 158.
Species Included	S. loryi (Gras, 1852);Oxfordian- Kimmeridgian, France. S. cheveti (Vadet, Nicolleau & Pineau, 1998) ; Upper Callovian, France, Morocco.
Classification and/or Status	Irregularia, stem group Atelostomata, Collyritidae.
Remarks	Differs from the type species of Collyrites in having a much shorter distance between the bivium and trivium sections of its apical disc. Eoholaster differs from Smithiaster in having its bivium farther from the periproct and in having only a very short distance between the bivium and trivium. In Smithiaster the distance separating the bivium and anus is between 0.23 and 0.30 of the total length of the test. Barras (2007, p. 158) chose Dysaster loryi as type species of this genus but unfortunately figured and based his description and diagnosis on a wrongly identified specimen (Museum National d'Histoire Naturelle, Paris A24446) which is, in reality, a Eoholaster lafittei. Barras, C. 2007. Phylogeny of the Jurassic to Early Cretaceous 'disasteroid' echinoids (Echinoidea; Echinodermata), and the origins of spatangoids and holasteroids. Journal of Systematic Palaeontology 5, 133-161. Vadet, A. 2008. Echinides nouveaux, peu ou mal connus. Annales de la societe d'Histoire Naturelle du Boulonnais 6 fasc. 2.
Contributor comments:	Barras 2007 p158 choose the type Dysaster loryi but he figure (5A-B; pl.2, fig. 8a-c) an Eoholaster lafittei A24446 from the Lambert's collection (MNHN de Paris), probably from the localitÃ?Â© type the Djebel Azreg. [Philippe Nicolleau, April 2009] Treated here as a junior synonym of Collyrites. [Andrew Smith, April 2009]