Gryphaeidae VYALOV, 1936

Richard Pokorný, Jaroslav Kaše, Jiří Kvaček, Kamil Zágoršek, Kočí, Tomáš & Žítt, Jiří, 2012, Fossils In Late Cretaceous To Early Palaeocene Flint Nodules Embedded In Pleistocene Glaciofluvial Sediments Near Fukov (Děčín District, Northern Bohemia), Acta Musei Nationalis Pragae Series B 68 (3 - 4), pp. 119-131 : 121

Family: Gryphaeidae VYALOV, 1936

M a t e r i a l: One poorly preserved valve, collection number: FZP/P/12/2-3/001.

D e s c r i p t i o n: Right valve, considerably inequivalve, oval in outline, slightly inequilateral. Length 8 mm, height 10 mm. Flat, lid-shaped, moderately convex. Muscle scar broadly oval, located approximately in the middle of the shell, near the top.

R e m a r k s a n d r e l a t i o n s h i p s: Due to the poor preservation and the absence of important features exact determination is not possible. According to the general shape, it is a solitary, semi-infaunal pycnodonteine oyster, probably with some relationship to the genus Pycnodonte FISCHER DE WALDHEIM, 1835 , which is described from the Upper Maastrichtian and Lower Danian (e.g. Müller 1970, Machalski 1988, Abdel Aal and El-Hedeny 1998, Casadío 1998). No fossil oysters have yet been confirmed from glacial sediments in the Czech Republic. Quite common findings are however known from Germany ( Hucke 1967, Lienau 2003). In sedimentary strata in situ, the presence of pycnodonteine oyster on a flint nodule surface is very frequent – for more information see Jagt et al. (2007) or Jolkičev (2007).

Ordo: Limida MOORE, 1952