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Thecosmilia

Milne Edwards, 1848, p. 468

Type Species

Lithodendron trichotomum Goldfuss, 1826, p. 45, pl. 13, fig. 6; Monotypy

Type Specimen: Neotype; MNHN F.R09988; Verified; Dry Preserved

Type Locality: Nattheim Upper Jurassic, Germany. (The original citation of Goldfuss is Giengen)

A first neotype was designated by Cuif 1965, p. 530, pl. 11 fig. 1-2 on the basis of a specimen from Nattheim figured by Fromentel, 1865, p. 15 n°108, pl. 6 fig. 4. A second non valid (ICZN 75-4) neotype was designated by Baron-Szabo (2002) among the specimens of the Goldfuss collection at Bonn. Both specimens are conspecific. Finally Lathuilière, Charbonnier and Pacaud (2017) designated a lectotype.

Classification

Synonyms

Description

Phaceloid/dendroid corallum with cylindrical corallites covered by costae. Epitheca s.l. of a variable development cover the costae according to species. Corallite circular to strongly distorted by the intracalicular increase. Radial elements are compact, unequal, bicuneiform costo-septa. They are free or occasionally joining near the central fossa. They are straight or curved or bent according to the intracalicular increase. Distal edge with regular teeth, lateral faces covered by granules and carinae organized in a montlivaltid microstructural and microarchitectural bauplan. No palus. Hexameral symmetry generally difficult to decipher because of the bilateral symmetry produced by the intracalicular increase. Abundant endotheca made of vesicular dissepiments. No columella in relief but inner edges of septa may join together in depth of the fossa, No synapticula. Parathecal wall.

Comparisons

There are transitional forms with other solitary (Montlivaltia) and colonial (Amblophyllia, Complexastrea, Latiphyllia) Montlivaltid morphogenera (see Lathuilière 1996). The name Thecosmilia has been attributed to many other phaceloid coral genera that do not have the montlivaltid septal structure. For this reason many Triassic and Liassic “Thecosmilia” have been reassigned to other genera such as Retiophyllia, Volzeia, Phacelostylophyllum, etc…

Remarks

26 Cretaceous and more than 100 Jurassic nominal species have been attributed rightly or wrongly to Thecosmilia

This page has been in preparation since 20-Aug-2009 09:32

This version was contributed by Bernard Lathuilière on 21-Jul-2017 16:35.

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


Sepcimen of Thecosmilia trichotoma, type species of the genus
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Specimen of Thecosmilia trichotoma, type species of the genus
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Specimen of Thecosmilia trichotoma, type species of the genus
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