Nota sobre los primeros registros de las algas calcáreas Paraepimastopora y Archaeolithophyllum en materiales del Mississippiense

Abstract

The Mississippian records of the calcareous algal genera Paraepimastopora and Archaeolithophyllum are re-evaluated, as these genera are usually considered to first occur or are confined to Pennsylvanian and Permian rocks. Most specimens of Paraepimastopora in Mississippian rocks have been documented in open nomenclature. Revision of the taxonomic characters permits to assign them to three species: Paraepimastopora cf. kansasensis (JOHNSON) ROUX, Paraepimastopora cf. noetschensis KRAINER & VACHARD, and Paraepimastopora sp. nov. cf. Paraepimatopora sp. A sensu GROVES. These species, although possibly first occurring rom the Tournaisian-Viséan boundary, are widespread in the late Viséan in many western Palaeotethyan basins. Revision of the taxonomic characters for Archaeolithophyllum suggests that the single species recorded in Mississippian rocks is Archaeolithophyllum lamellosum WRAY, a taxon rarely recorded in western Palaeotethyan basins, although now first recorded in Ireland and Scotland during the late Brigantian. Subsequently, the species is present in the Serpukhovian (late Mississippian) of France, Spain and Poland. In the Bashkirian (early Pennsylvanian) the genus diversified with several species recorded, and with a notable increase in the abundance of specimens elsewhere.