Trocharea
Etallon in Thurmann and Etallon 1864, p. 411
Type Species
Trocharea actiniformis Etallon in Thurmann and Etallon 1864, p. 411, pl. 58 fig. 4; Monotypy
Type Specimen: Syntype; ?; Lost; Unknown
Type Locality: « Hypovirgulien » (Kimmeridgian, Upper Jurassic) from Croix-dessus (Switzerland)
Classification
Diagnosis
Solitary microsolenid with a wide fixation area and strong trabeculae
Description
Solitary trochoid , patellate, discoid or pedunculate corallum with a fixation area. calice elliptical to circular in outline. Epitheca present or absent according to species. Radial elements are pennular straight, subequal, perforate anastomosed costosepta. Distal edge moniliform. Radial symmetry. Endotheca of few thin dissepiments. Axial zone with a columella parietal and rudimentary or a small fossa according to species. synapticulae present, synapticulothecal wall (or pennular envelope ?).
Comparisons
Alloiteau 1957 and Fischer 1969 remarked that Trochoplegma differs from Trocharea by its tendency of compactness in septa of first order. The smaller size of trabecules and the slightly dipping outward menianae are other possible criteria. Chomatoseris is free living, Trochoplegmopsis has a papillose columella.
Remarks
5 Jurassic nominal species known. See Beauvais 1964, Fischer 1969, Pandey and Fürsich 1994.
Distribution
- Western Europe, Southern Europe, South Asia; Middle Jurassic - Late Jurassic
This page has been in preparation since 20-Aug-2009 09:35
This version was contributed by Bernard Lathuilière on 11-Feb-2011 17:22.
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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