Placogyra
Koby, 1904, p.21
Type Species
Placogyra felixi Koby , p.22, pl. 3 fig. 5; Monotypy
Type Specimen: Lectotype; 61; Not Traced; Dry Preserved
Type Locality: Upper Jurassic, Upper Oxfordian (Bimammatum zone), Couches de Montejunto of Pragança scarp (Portugal)
The lectotype (erroneously called holotype), n°61 of the geological Service Lisboa, coll. Choffat, was figured and redescribed in Beauvais 1970, p. 1121. Additional informations about the genus are in Eliasova 1973.
Classification
Description
Massive meandroid corallum with corallites in series produced by intratentacular increase or isolated corallites. Externally covered by a granulated tectura. Highly variable collines: tectiform, tholiform or depressed. If present, the peritheca is narrow. Radial elements are compact, free, straight, bicuneiform costosepta. They are alternately thick and thin. Inner edge of primary septa with T-form enlargements, tertiary septa attenuated. Apophysal septa and lonsdaleoid septa exist. No palis. Rhipidogyrid microstructure. Strong bilateral symmetry. Endotheca present. Columella lamellar, synapticulae absent but tigella possibly present in depth between primary septa and the columella. Wall probably septoparathecal and thickened in stereozone.
Comparisons
Very close of Psammogyra, which has a smooth wide peritheca. Placogyra has also shorter series.
Remarks
Two nominal species known in Jurassic and one in Cretaceous.
Distribution
- Southern Europe, Central Europe, Eastern Europe; Late Jurassic - Early Cretaceous
This page has been in preparation since 19-Aug-2009 16:54
This version was contributed by Bernard Lathuilière on 09-Nov-2012 17:23.
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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