The Echinoid Directory

Contributed by Andrew Smith, February 2008

Jaubertisoma Vadet, Nicolleau & Reboul, 2010 , p. 33

Diagnostic Features
  • Test depressed in profile.
  • Apical disc relatively small; plating lost.
  • Ambulacra polygeminate throughout with pore-pairs in a double offset series in each half. Plate compound style unknown.  A single large primary tubercle to each compound plate; almost as large as the adjacent interambulacral tubercle.
  • Interambulacral plates dominated by a single large primary tubercle with narrwo adradial and interradial bands of granules.  
  • Peristome relativel large with obvious buccal notches
  • Spines and lantern unknown.
Distribution Middle Jurassic (Bathonian), France
Name gender neuter
Type Leiosoma jauberti Cotteau, 1863, p. 87, by original designation.

Figured syntype: University of Lyon Palaeontological Collections EM40328 (Cotteau collection - figured Cotteau, G. 1883, Paleontologie Francaise. Terrain jurassiques, X. Pl. 411, figs 6-7).
Species Included Only the type species was included.
Classification and/or Status Echinacea, Stomopneustoida, Stomopneustidae

A subjective junior synonym of Phymechinus
Remarks Vadet et al. (2010) established this genus citing Leiosoma jauberti Cotteau (a Bathonian species from France) as the type, but illustrating under that name a specimen of a different species from an unspecified locality and horizon in the Middle Jurassic (Bajocian-Bathonian) of the Atlas Mountains, Morocco.  The name Jaubertisoma must reside with Cotteau's type specimen, which is clearly a species of Phymechinus. 

Vadet, A., Nicolleau, P. & Reboul, R. 2010. Les Echinides de l'Atlas marocain: Bajocien Bathonien. Premiere partie: les reguliers. Annales de la Societe d'Histoire Naturelle du Boulonnais 9/1, 1-40.