New brachiopods from the Lower-Middle Ordovician [Billingen-Volkhov stages] of the East Baltic

Two new rhynchonelliformean brachiopods, Neumania paucicostata sp. nov. and Leoniorthis robusta gen. et sp. nov., are described from the Billingen and Volkhov stages (Lower–Middle Ordovician: Arenig) of the Baltic–Ladoga Klint area. All specimens were washed out from unconsolidated sediments, and were sampled in Tallin, Estonia, and at three localities in St. Petersburg district, Russia. Numerous specimens were found in a large mud mound, the lower part of which is within the Baltoniodus triangularis conodont Zone, otherwise usually missing in this area. L. robusta is here assigned to the family Orthidae.