Macgeopsis
Alloiteau, 1957, p. 95
Type Species
Epismilia grandidieri de Fromentel in Fischer 1873, p. 113; Original Designation
Type Specimen: Lectotype; MNHN M05088; Verified; Dry Preserved
Type Locality: Liassic ? or more probably Upper Bathonian of Morondava, Madagascar
The type-specimen considered as lost in Alloiteau (1957) was found and considered abusively as a holotype (Alloiteau 1958). A paralectotype exists, strongly compressed and additional thin sections were done by Alloiteau 1958
Classification
Description
Solitary corallum with a subcircular calice, proximally arched. Wrinkled epitheca, but discrete costae. Radial elements are compact, unequal, free (minor) and anastomosed (major) sinuous septa (or costosepta ?). Thickness constant to variable, bicuneiform to attenuated toward the inner edge. Distal edge smooth, steep near the wall, lateral faces with very small and numerous regularly distributed granules. Occasionally a detached tooth on the inner edge. No pali. Microstructure non trabecular with laminar layers. Hexameral symmetry present with disctinct categories of size order in septa. Bilateral symmetry marked by the elongation of the central fossa and the proximo-distal curvature of the corallum. Endotheca made of tabuloid dissepiments steeply inclined near the wall. Columella parietal. Synapticules absent. Paratheca peripheral, cutting, in continuity with non trabecular septa.
Remarks
Six nominal species known in Jurassic
Distribution
- Western Europe, Subsaharan Africa, Central America; Early Jurassic - Late Jurassic
cited also in Saoudi ArabiaThis page has been in preparation since 19-Feb-2010 10:24
This version was contributed by Bernard Lathuilière on 19-Feb-2010 16:55.
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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