Myriophyllia
Orbigny, 1849, p. 8
Formerly placed in the Stylinidae because of the styliform columella, it has been moved by authors to the Faviidae because of the big trabeculae producing lateral axes and big granules, and the occurrence of trabecular lobes at the inner edge.
Type Species
Meandrina rastellina Michelin, 1843, , p. 99 pl. 18 fig. 7; Original Designation
Type Specimen: Lectotype; MNHN ; Lost; Unknown
Michelin described syntypes from Is sur Thil (Côte d’Or), Saint Mihiel (Meuse) and Lifol (Vosges). Alloiteau (1957) wrongly designated a holotype (in fact a lectotype) from Saint Mihiel. Beauvais (1964) did not find the type specimen and selected a neotype in the Michelin’s collection. Unfortunately, as she did not designate clearly the selected specimen, this neotype is not valid. We can just suspect that the paralectotype numbered F.R10739 was selected by her because it was photographed. Presently, only paralectotypes are available in MNHN Paris. It seems they all belong to the same genus.
Classification
Homonyms
Description
Massive meandroid corallum with long, straight or sinuous valleys separated by collines without ambulacrum. Centers rather distinct by the curvature of septa, by the presence of a styliform columella and, occasionally by the occurrence of valley septa between centers. Centers in one row within a valley width. Radial elements compact or subcompact, free or joining in the middle of the valley, often with a cuneiform shape, straight, curved or bent, unequal in length and thickness. Inner edge of major septa with a trabecular lobe and with episodic junctions to the columella producing some “pores” , lateral faces with big round granules, no palis. Microstructure with big trabecules producing lateral round granules. Strong bilateral symmetry related to the intracalicular increase. Endotheca made of wide tabuloid dissepiments concave upward in the center of valleys, possibly more vesiculous near the wall, columella styliform; no synapticulae, septothecal wall made both by enlargement of external edge of septa and by fusion with other septa of the adjacent valley
Remarks
Strangely, d’Orbigny in his initial description indicates that a sulcus exists on top of collines. Nevertheless the different syntypes of Michelin do not show such a sulcus or ambulacrum. Then subsequent authors considered that Myriophyllia has no ambulacrum. Complementary descriptions can be found in Alloiteau (1957), Beauvais (1964), Roniewicz (1966; 1976), Baron Szabo (2002). 6 Jurassic and 10 Cretaceous nominal species are known,
Distribution
- Western Europe, Southern Europe, Central Europe, Eastern Europe, North Africa, Central Asia, East Asia, Caribbean, South America, Southeast Asia; Late Jurassic - Early Cretaceous
This page has been in preparation since 19-Aug-2009 16:04
This version was contributed by Bernard Lathuilière on 01-Oct-2016 08:55.
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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