Pleurosmilia
Fromentel, 1856, p.853
Pleurosmilia Fromentel, 1856, p.853 is a junior synonym (available and invalid), see Axosmilia Milne Edwards, 1848, p. 467.
Type Species
Pleurosmilia grandis Fromentel 1856, p.854.; Subsequent Designation Fromentel 1867, p. 244
Type Specimen: Syntype; MNHN A32894; Verified; Dry Preserved
Type Locality: Kimmeridgian (Upper Jurassic) Mantoche (France)
Only one syntype remains. One sample not sectioned rather badly preserved. Alloiteau designated erroneously P. graciosa as the type-species.
Classification
Description
(from the syntype) Solitary corallum with trochoid to turbinate shape. Epitheca incomplete, costae subequal. Corallite outline slightly elliptical, infundibuliform. Radial elements compact, free, attenuated or bicuneiform, straight to curved, unequal. Their higher part is at the outer edge. Distal edge, inner edge and lateral faces not observed, no palis. Microstructure not observed. Hexameral symmetry difficult to decipher due to the bad preservation, bilateral symmetry obvious with the central fossa. The central fossa was obviously excavated (probably in order to find the lamellar columella described by Fromentel). Endotheca present, columella lamellar (from Fromentel’s text, not observed on the sample, probably due to the bad preservation, synapticulae absent, Wall peripheral and cutting.
Remarks
Recently Roniewicz 2008 proposed to keep distinct Axosmilia and Pleurosmilia on the basis of the infundibuliform character in Axosmilia and exsert calice in Pleurosmilia . This could correspond to a septal versus costo-septal differentiating structure. A gradation is suspected between these two situations. Even if it is taxonomically plausible, this distinction is nomenclaturally not supported by the examination of the type material. 36 Jurassic and 16 Cretaceous nominal species.
This page has been in preparation since 02-Jun-2007 12:36
This version was contributed by Bernard Lathuilière on 15-Mar-2013 15:54.
Page authors are: Bernard Lathuilière. Please contact the editor if you would like to contribute to the diagnosis of this taxon.
The editor is: Bernard Lathuilière
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