Uniformity of tropical micromorphic brachiopods from the Lower Devonian: lingulates from the section Compte-I of Spanish Central Pyrenees

Abstract

Lingulate brachiopods of the Lochkovian and Pragian age from the Compte-I section in the Spanish Central Pyrenees are described to elucidate the evolutionary history of this brachiopod group. Precise bio- and chronostratigraphic position of the brachiopod association is supported by the conodont records, which allows recognition to the threefold Lochkovian subdivision and an approximation of the base of the Pragian. The samples yielded nine taxa, generally poorly preserved and therefore mostly determined only to generic level as Barrandeoglossa , Acrosaccus , Chynithele , Lochkothele , Praeoehlertella , Schizotreta and Havlicekion . This assemblage is similar to micromorphic lingulate brachiopod assemblages from the Lower Devonian in the Barrandian area (Czech Republic) and New South Wales (Australia) confirming hypothesis of general uniformity of micromorphic brachiopods in low latitude periphery the Gondwana palaeocontinent during the Lower Devonian. Dominance of small discinoids, and a glossellid Barrandeoglossa associated to a micromorphic biernatiid Havlicekion cf. holynensis indicates a moderately shallow environment, similar to the one that took place during the deposition of the Kotýs Limestone in the Barrandian area. This interpretation is in agreement with previous palaeoenvironmental inferences for this section based on microfacies studies, Magnetic susceptibility, and Gamma-Ray spectrometry analyses.