Stephanastrea
Etallon, 1864, p. 401
Type Species
Stephanastrea ramulifera Etallon, 1864, p. 402, pl. 57 fig. 2; Monotypy
Type Specimen: Syntype; n° ??; Lost; Unknown
Type Locality: Oxfordian (Epicorallien of Etallon, Upper Jurassic) of Laufon (Switzerland).
The type material is not in the Etallon's collection in Porrentruy, nor in Paris, nor in Dijon. The genus is described with help of Stephanastrea ramulifera from the Koby's collection S 2234 (new number A1.8.3(3)) from La Caquerelle
Classification
Description
Massive to ramose cerioid subthamnasterioid corallum. Corallite polygonal in outline, intercalicinal increase Radial elements confluent, compact, bent at the place of the wall, septa of small size order contratingent. Distal edge with equal regular teeth, inner edge not observed, lateral faces not observed, pali present as small relieves and thickenings at the place of anastomoses. The two crowns initially described by Etallon were not seen. Microstructure unknown in the type species. Hexameral symmetry, no bilateral symmetry. Endotheca not observed , columella styliform, synapticulae probably absent, wall often not observed distally (subthamnasterioid pattern), of unknown nature.
Comparisons
Relationships with Allocoenia created in 1859 still need to be clarified. Actinastrea, based on a Cretaceous species, has been widely merged (Geyer 1955a) with the group Allocoenia-Stephanastrea but is probably different by the nature of the wall. Enallocoenia needs the designation of a neotype to be compared Coenastrea has no palis Allocoeniopsis is probably a junior synonym. Chondrocoenia has a tendency to be plocoid and costae have bigger trabeculae than septa.
Remarks
Five Jurassic and 3 Cretaceous nominal species
This page has been in preparation since 20-Aug-2009 07:46
This version was contributed by Bernard Lathuilière on 01-Apr-2013 17:00.
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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