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Enallocoenia

Orbigny, 1849, p. 7

Type Species

Astrea crassoramosa Michelin, 1843, p. 109, pl. 25 fig.2; Monotypy

Type Specimen: Neotype; MHNG GEPI 61505; Verified; Dry Preserved

Type Locality: Oxfordian (Upper Jurassic). Initial syntypes from Maxey sur Vaize and Saint Mihiel (France) , neotype from Noirmont (Switzerland)

Syntypes were searched in MNHN Paris without success. A neotype was selected by Beauvais (1964 p. 111). It is the specimen figured by Koby (1885, pl. 87, fig.2). Descriptions of the type species can be found in Koby (1885) and Beauvais (1964).

Synonyms

Description

Colonial ramose, cerioid. Calices polygonal delimited by a wall, sometimes hidden in depth. Extracalicular increase. Radial elements are compact, straight, free, almost confluent occasionally subconfluent. Lateral faces of septa granulated. Axial symmetry of variable order with clear size orders. S1 and S2 of a corallite are often confluent with S3 of the neighbouring one. Distal edge dentate. Synapticules absent, columella styliform. Dissepimental endotheca. Wall of unknown nature lower than distal edge of radial elements.

Comparisons

Enallocoenia must not be confused with Actinastrea, Stephanastrea, Allocoenia, Allocoeniopsis, Chondrocoenia, Stephanocoenia because of free septa and absence of palis.

Remarks

Geyer has grouped all the small Jurassic cerioid forms in the Cretaceous genus Actinastrea and he was unfortunately followed by many authors. More anciently, Koby placed all these forms in two similar genera: the Tertiary Astrocoenia and the Recent Stephanocoenia .

This page has been in preparation since 18-Aug-2009 17:36

This version was contributed by Bernard Lathuilière on 28-Apr-2017 08:34.

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


Neotype of Astrea crassoramosa type species of the genus
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Neotype of Astrea crassoramosa type species of the genus
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Neotype of Astrea crassoramosa type species of the genus
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Neotype of Astrea crassoramosa type species of the genus
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