Pennsylvanian brachiopod, fish and conodont faunas from the Caliza Masiva (San Emiliano Formation) at the Mina Profunda area, Cantabrian Zone, NW Spain

Abstract

A rock sample obtained from the Caliza Masiva of the San Emiliano Formation (Bashkirian–early Moscovian) in the Mina Profunda area (NE Villamanín) of the Bodón Nappe (Cantabrian Zone, NW Spain) has yielded numerous brachiopods and fish remains not frequently represented in the fossil record. The brachiopod assemblage comprises 13 taxa and is characterized by phosphatic (Langella, Orbiculoidea) as well as exceptionally preserved silicified calcitic elements (a small chonetid, Composita, Crurithyris, Lambdarina, and two minute terebratulids) as the main faunal components. Of special importance is the record of the microbrachiopod Lambdarina winklerprinsi nov. sp., which reduces the large Viséan–Upper Permian gap in the stratigraphic record of this genus. Conodont elements recovered from the same insoluble residue are indicative of the upper Bashkirian Idiognathoides sulcatus parvus Zone. The accompanying fish remains consist of chondrichthyan teeth and scales, an acanthodian scale and osteichthyan tooth-bearing bones, isolated teeth and isolated scales, representing the first Pennsylvanian ichthyoliths analyzed from the Cantabrian Zone. The limestone beds with selective silicification in the San Emiliano Formation provide an exceptional opportunity to improve our knowledge on the patterns of life diversity over geological time.