Meandropsis

Krasnov, 1964, p. 87

available name but not valid. Junior synonym.

Type Species

Meandrina tenella Goldfuss, 1826: p.63; Monotypy

Type Specimen: Holotype; IPB 211; Verified; Dry Preserved

Type Locality: The label says as the Goldfuss' book " Jura Malm von Giengen" but the preservation suggests it comes from the Upper Cretaceous of Gosau.

the holotype is a sectioned specimen beautifully preserved. The sample shows another thamnasterioid associated colony.

Description

Massive meandroid colony with parallel and meandering series, continuous collines, probably no ambulacrum. Radial elements are compact confluent or not confluent costosepta. Generally straight, but some are internally bent toward a discreet mouth, thin septa are in zigzag. Radial elements show vertically very regularly spaced teeth on inner edge. They are often attached to a lamellar linkage systematically present and continuous in the valley. Septa are often globally attenuated but enlarged at their inner edge. They are strongly ornamented with acute or horizontally flattened granules arranged regularly on the lateral faces of the costosepta They come from the branching of trabeculae arranged in water jet within the costosepta.. In transverse section a median line is clearly visible in the mid septal plan and some branching that join the granules. The axial structure is a valley septum regularly attached to the inner bent edge of septa. Endotheca is made of thin cellular dissepiment that thicken in the "axial" region and constitute tabuloid dissepiments. The wall located in the colline region is a septotheca mainly made by enlargement of costo-septa (rare abortive costo-septa).

Remarks

The type-species is reaassigned to Orbignigyra or Meandroria (Baron Szabo 2002, Löser 2000)

This page has been in preparation since 19-Aug-2009 15:55

This version was contributed by Bernard Lathuilière on 19-May-2012 17:47.

Page authors are: Bernard Lathuilière. Please contact the editor if you would like to contribute to the diagnosis of this taxon.

The editor is: Ann Budd