Astraeomorpha
Reuss, 1854: 127
Type Species
Astraeomorpha crassisepta Reuss, 1864: 127, pl.16, fig. 4-7; Monotypy Reuss, 1854: 127
Type Specimen: Neotype; NHMW 1982/56/37-2; Verified; Dry Preserved
Type Locality: Kesselwand-Rohrmoos, Gosaukamm region, Northern Calcareous Alps. Zlambach Beds, Rhaetian, Late Triassic
The Reuss type specimen has been lost. The neotype (chosen by Roniewicz 1989:95) origins from the region the nearest possible to that from the Reuss fauna was described, i.e. from the region of Gosau. Many specimens from the Rhaetian of Kesselwand-Rohrmoos, Fischerwiese, Sommeraukogel and Zlambachgraben are housed in NHMW and GBA.
Classification
Diagnosis
Colony thamnasterioid, budding intercalicular. Septa solid, distal edge smooth, lateral faces with menianes and synapticulae. Inner margin with regularly distributed projections. Columella styliform, thin. Dissepiments thin-walled, vesicular. Septal midline continuous or differentiated into densely arranged trabeculae. Menianes provided with axis.
Description
Descriptions of morphology and microstructure of the type species, with illustrations, are given in Cuif 1975: 116-121, text-fig.19, pl.17,fig.1-7, Roniewicz 1989:94, pl.28,fig.3-5, and Gautret et al. 1992:352, text-fig.1a;pl.1,fig.8,9; pl. 2,fig.5-9.
Comparisons
From thamnasterioid, small-corallite genus Seriastraea Schaefer et Senowbari-Daryan, Astraeomorpha differs in short, thick, non-perforated septa, and thick columella; from Parastraeomorpha Roniewicz, it differs in development of menianes. Comparisons of Astraeomorpha with representatives of the family Spongiomorphidae have been presented by Gautret et al. 1992 and Ezzoubair and Gautret 1993; in conclusion the authors postulated inclusion of the spongiomorphid genera (Spongiomorphidae Frech, 1890) to the Astraeomorphidae Frech, 1890.
Remarks
The earliest Astraeomorpha is that described by Volz, 1896:61 form the Carnian. First illustrations of microstructure of A. crassisepta were presented by Cuif 1975: text-fig. 19 and pl.17. Emendation of the generic diagnosis, description with illustrations of septal microstructure of the type and other species is presented in Roniewicz 1989:94, pls. 28 and 29. In Gautret et al. 1992 the microstructure of Astraeomorpha is discussed, and illustrated in pl. 1: 7-9. Seven species have been described, from this number the type species is the most frequently cited.
Distribution
- Southern Europe; Late Triassic
- Central Europe; Late Triassic
- Central Asia; Late Triassic
- North America; Late Triassic
- Central America; Late Triassic
- South America; Late Triassic
The genus is known beginning from Carnian in the Dolomites, through the Norian in Europe and America to the Rhaetian in Europe and Asia.This page has been in preparation since 22-Mar-2009 14:32
This version was contributed by Ewa Roniewicz on 09-Nov-2010 14:45.
Page authors are: Francesca Benzoni Ewa Roniewicz. 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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