Bracthelia
L. and M. Beauvais, 1975: 576
In colony and corallite structure, and above all, in the microstructure, this Bathonian coral is similar to Tithonian Ironella Starostina and Krasnov, 1970: 79, and especially to Oxfordian-Kimmeridgian Ironella rutimeyeri (Koby,1889) described and illustrated in Roniewicz 1976: 83, pl. 21, fig. 2, 3.
Type Species
Bracthelia collignoni L. Beauvais and M. Beauvais, 1975, p. 580, pl. 1 fig. 1, 3.; Original Designation
Type Specimen: Holotype; MNHN A 32871; Verified; Dry Preserved
Type Locality: Bathonian of Madagascar
Classification
Description
Massive plocoid corallum, intercalicular increase. Peritheca granulated made of trabecular layers (but possibly also of dissepimental layers). Corallites circular to elliptical in cross section. Radial elements compact free bicuneiform straight unequal costoseptae. Distal edge dentate, inner edge with flabelliform auriculae, lateral faces ornamented with irregular granules, palis absent. Microstructure rhipidogyrid. Radial (hexameral for the type species) symmetry, bilateral symmetry often present, characterised by the elongation of the columellar space. Endotheca poorly abundant, variable columella styliform sublamellar to parietal and absent according to calices and species, synapticulae absent, septothecal wall with rudimentary septa.
Remarks
We group within Bracthelia the Bathonian type species and the various upper Jurassic and Cretaceous species of Ironella (Starostina and Krasnov 1970, non Ironella Cobb 1920). These Upper Jurassic species may display a less solid and more variable columella and a higher proportion of vesicular peritheca.
This page has been in preparation since 07-May-2009 07:43
This version was contributed by Bernard Lathuilière on 21-Nov-2013 16:58.
Page authors are: Ewa Roniewicz 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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