Tiaradendron
Quenstedt, 1857, p. 714
Tiaradendron appeared first discreetly as a subgenus in Der Jura by Quenstedt (1857). Subsequently the name appeared several times with the wrong spelling “Tiarodendron”. It was considered as a genus from Quenstedt (1880) until now.
Type Species
Lobophyllia germinans Quenstedt, 1852, p. 654 pl. 58 fig. 18; Original Designation
Type Specimen: Lectotype; GPIT AN/1147; Verified; Dry Preserved
Type Locality: Kimmeridgian (Upper Jurassic) from Nattheim (Germany)
A lectotype was chosen by Beauvais 1970, p. 1113, pl. 2 fig. 2. Lauxmann (1991, p. 135, pl. 3 fig. 4-8) gave a complementary description and figuration of the type species and other species on the basis of a wide collection.
Classification
Description
Dendroid corallum with branches flattened according to a surface defined by two overdeveloped costosepta. Tectura with fine tight regularly arranged granules. Extracalicinal increase. Radial elements are compact, free, bicuneiform, straight, strongly unequal costosepta. Distal edge smooth, inner edge with large auricules, lateral faces finely granulated. No palis. Microstructure unknown, most probably rhipidogyrid. Hexameral to octameral symmetry preserved, despite the development of overdeveloped septa that are often opposite and define a bilateral symmetry. Endotheca not observed, columella absent, synapticulae absent. Wall probably paraseptothecal.
Comparisons
The overdevelopment of two septa produces a completely original bauplan in Scleractinia that has no equivalent.
Remarks
3 nominal species in Jurassic among which one passed through the Jurassic-Cretaceous boundary.
Distribution
- Western Europe, Southern Europe; Late Jurassic - Early Cretaceous
This page has been in preparation since 20-Aug-2009 09:33
This version was contributed by Bernard Lathuilière on 28-May-2016 09:53.
Page authors are: Bernard Lathuilière Ewa Roniewicz. 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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