Cambrian‐Ordovician lingulate brachiopods from Scandinavia, Kazakhstan, and South Ural Mountains

Abstract

Lingulate brachiopods are described from the Upper Cambrian - Lower Ordovician (Tremadoc-Arenig) of Scandinavia (Sweden, Denmark, and Norway), South Ural Mountains, northeastern Central Kazakhstan, and the southern Kendyktas Range in southern Kazakhstan. The faunas comprise a total of 56 species of which 20 are new these are assigned to 40 genera, of which the lingulids Agalatassia and Keskentassia, the siphonotretid Siphonotrerella. and the acrotretids Galinella, Longipegma, Ottenbyella, Akmolina, Mamatia, Sasyksoria, and Otariella are new. The new Subfamily Elliptoglossinae is proposed. The poorly known Cambrianardovician stratigraphy of the South Urals. northeastern Central Kazakhstan, and the southern Kendyktas Range is reviewed. Many sequences in these areas that were previously referred to the Upper Cambrian and Tremadoc can now be correlated with the lower Arenig Hunneberg Stage in Baltoscandia. Three main types of faunal assemblages can be distinguished: (1) the Broeggeria assemblage; (2) several microbrachiopod assemblages; and (3) the Leptembolon-Thysanotos assemblage. The Broeggeria assemblage is distributed world-wide in the Tremadoc of the southern Kendyktas Range, Scandinavia, Belgium, Great Britain, Canada, and Argentina, while the Leptembolon-Thysanotos assemblage is confined to the Arenig of an area surrounding the East European platform, including northern Estonia, Poland, Germany, Bohemia, Serbia, and the South Urals. The microbrachiopod assemblages are known mainly from the Upper Cambrian - Arenig of Scandinavia, South Ural Mountains, northeastern Central Kazakhstan, and the southern Kendyktas Range.