Thamnasteriamorpha
Melnikova, 1971:31
Thamnotropis Cuif, 1975 is objective junior synonym
Type Species
Thamnastraea frechi Volz, 1896:59, pl. 6, fig. 1-10; Original Designation Melnikova, 1971:31
Type Specimen: Lectotype; MGUWr 77sz,79’sz; Verified; Thin Section
Type Locality: Misurina, Dolomites, Southern Alps. Carnian, Late Triassic
Classification
Synonyms
Diagnosis
Thamnasterioid. Radial elements of biseptal type a/o bicostoseptal type. Menianes continuous, with borders directed upwards. Wall lacking. Columella styliform. Synapticulae present. Dissepiments vesicular. Epitheca (holotheca) present. Trabeculae of (80)-100-130)µm in diameter.
Description
Morphology described in Volz 1896. Microstructure of T. frechi Volz was characterized and illustrated by Cuif, 1976: 121- 124,pl.18,figs 1-4, text-fig.20.
Comparisons
In colony structure Thamnasteriamorpha resembles Periseris Ferry and Astraeomorpha Reuss. It differs from Periseris elegantula in perfectly compact septa, in mode extracalicular of colony increase, but essentially differs in trabecular dimensions approximately three times thinner than those in the latter. In regular distribution of continuous menianes having margins directed upward it resembles Astraeomorpha, from which differs in thin septal blade (between the menianes), and in bicostoseptal type of radial elements.
Remarks
From three species originaly considered to be Thamnasteriamorpha, only the type species represents the genus. Two others were transmitted to a new genus, Afghanastraea Melnikova, 1987. described.
Distribution
- Southern Europe; Late Triassic
Dolomites, Southern Alps, Carnian.This page has been in preparation since 25-Apr-2009 17:39
This version was contributed by Ewa Roniewicz on 11-Nov-2010 12:00.
Page authors are: Francesca Benzoni. Please contact the editor if you would like to contribute to the diagnosis of this taxon.
The editor is: Ewa Roniewicz
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