New records of brachiopods and crinoids from the Silurian (Wenlock) of the southern Urals, Russia

Abstract

Crinoids and brachiopods are described from the Silurian Uzyan Formation of the Zilair Zone in the southern Urals. The occurrence of the graptolites Coronograptus praedeubeli suggests a late Homerian (Wenlock) age for the strata. A new disparid crinoid, Cicerocrinus gracilis Donovan sp. nov., is the oldest known member of this genus. It has a long, flexible and homeomorphic column, and a tall bryozoan palaeontology terminology (IBr 2 ) (second primibrachial) axillary. All species of Cicerocrinus described previously have been limited to the Ludlow of the British Isles, Sweden and Estonia, and the Pridoli of Estonia. The poorly preserved brachiopod fauna is represented by small atrypid (Atrypa? sp.) and dalmanellid brachiopods (Levenea? sp.). The reported assemblage generally inhabited deep-water environments.

Kalana Lagerstätte crinoids: Early Silurian (Llandovery) of central Estonia

“…Besides Avalonia and Baltica faunas, relatively little is known about Silurian crinoids (crown-based taxa) from the remainder of Europe. Recently, one Wenlock taxon was described from the southern Urals (Bogolepova et al, 2018). Crinoids are also known from the Ludlow of the Czech Republic, and scyphocrinitidae are known from several sites in the Silurian-Devonian boundary strata (Webster and Webster, 2013).…”