Corals from Asturian substage in Cantabrian Mountains: A review

Abstract

The subdivision of the Pennsylvanian divided the Namurian, Westphalian and Stephanian regional stages in substages named with letters. During the second half of the 20th Century, some of these substages were more properly defined. Westphalian A, B and C were defined as Langsettian, Duckmantian and Bolsovian. The Stephanian A was renamed as Barruelian and the transition between Westphalian and Stephanian as Cantabrian. The Westphalian D, defined in continental strata from Saar-Lorraine, was proposed to be substituted by the Asturian substage with the stratotype in the Cantabrian Mountains. An extensive documentation with assemblages and stratigraphic distribution of plants, fusulinids, brachiopods, corals, molluscs and ostracods was presented. But a formal definition of the stratotype was never proposed. The Asturian substage in the Cantabrian Mountains comprises both marine and terrestrial strata rich in fossils and allows easy correlations with other areas. Recent studies have improved the stratigraphic data and the knowledge on the coral assemblages, mainly in the eastern area of Asturias and Palencia. The entire coral assemblage from Asturian substage in the Cantabrian Mountains is composed of 48 named species and 20 species described in open nomenclature. The short stratigraphic range of many of them may be the basis for the characterization of the Asturian stage with corals. Although some species are endemic in the Cantabrian Mountains, there are some species that are also present in other regions of the Palaeotethys. At the generic level there are significant similarities that should be the basis for wider correlations with North America and East Asia.