New Species of the Genus Lambeoceras Foerste (Actinocerida)from the Upper Ordovician of the Middle Siberia
History of the study, taxonomy and distribution of the actinoceratid genus Lambeoceras Foerste are discussed. Three new nominal species and one form in open nomenclature from the Upper Ordovician (Nerundinskii horizon, Catskii stage) of Middle Siberia (basin of the river Podkamennaya Tunguska) are described.