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Meandrarea

Etallon, 1859 p. 128

Meandrarea Etallon, 1859 p. 128 is a junior synonym (available and invalid), see Comoseris Orbigny, 1849: 12.

Type Species

Meandrarea marcouana Etallon, 1859 p. 128,; Original Designation

Type Specimen: Syntype; MNHN M03374; Verified; Dry Preserved

Type Locality: Kimmeridgian (Upper Jurassic) of Valfin (France)

Some authors erroneously considered M. gresslyi as the type-species when Etallon himself designated M. marcouana as the type-species. There are 4 syntypes in the MNHN collection in Paris. Some small parts of them were polished.

Classification

Description

(based on syntypes) Massive meandroid corallum with short to elongated valleys. No observed epitheca. Intracalicular increase producing sinuous valleys, rather radially arranged, at least at the margin of the colony. Valley septa not systematically present and distinct, collines without ambulacrum, rather tholiform, occasionnaly tectiform. Radial elements pennular, perforate, anastomosed, straight to curved, subequal. Distal edge moniliform with equal regular teeth. No palis. Radial symmetry disturbed by bilateral symmetry, elongation of valleys and anastomoses of septa. Endotheca not observed. Center of calices with a small fossa not very distinct in which small trabecules may be tightly arranged. Synapticulae present, especially near the collines. Wall probably synapticulothecal.

Remarks

Meandraraea is currently distinguished from Comoseris by the straight series, the tectiform collines, a skeleton less porous... (see Roniewicz 1976) Based on the description of the four syntypes of the type-species, I see no reason to keep this genus apart from Comoseris. 19 Jurassic and 21 Cretaceous nominal species known.

This page has been in preparation since 16-Feb-2010 13:18

This version was contributed by Bernard Lathuilière on 14-Mar-2014 16:39.

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


syntypes of Meandraraea marcouana type species of the genus
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syntype of Meandraraea marcouana type species of the genus
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syntype of Meandraraea marcouana type species of the genus
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syntype of Meandraraea marcouana type species of the genus
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