Pentamerella sp.

Mergl, Michal & Budil, Petr, 2019, Rhynchonelliform Brachiopods And Trilobites Of The ‘ Upper Dark Interval’ In The Koněprusy Area Devonian, Eifelian, Kačák Event; The Czech Republic, Fossil Imprint 75 (1), pp. 92-107 : 97-98

Pentamerella sp.

Pl. 2, Figs 4, 5

M a t e r i a l. One dorsal valve (PCZCU 2275) and one ventral valve (PCZCZU 2276).

D e s c r i p t i o n. The shell is thick walled, strongly biconvex, 5 mm wide, most likely rectimarginate. The dorsal valve is transversely oval, with a length 80 % of the width and widest in the posterior one-third region. Maximum convexity is in the posterior one-third. Posterior corners are rounded, slightly flattened. The ventral valve is subpentagonal, more elongate, strongly convex in posterior third. Ornamentation is formed by ten strong costae in the dorsal valve and nine costae in the ventral valve. The costae are weakly defined at the beaks, but progressively increase anteriorly. There are three coarser median costae in the dorsal valve and two coarser costae in the ventral valve compared to those on the flanks.

R e m a r k s. The shells are referred to Pentamerella HALL, 1867 due to their small size, thick shell and coarse costae, but lack of data about the interior makes this affiliation only tentative. The specimens may be related to some yet undescribed small pentamerid which is present in the upper part of the Acanthopyge Limestone (Eifelian, Tortodus kockelianus Zone ) in the Koněprusy area.

O c c u r r e n c e. UDI, samples TM 10, TM 12.