Abstract:
The evolution of the Permian ammonoid family Spirolegoceratidae is discussed and a new phylogenetic reconstruction is proposed based on new data. Two subfamilies are recognized within the family Spirolegoceratidae: Spirolegoceratinae Nassichuk and Sverdrupitinae subfam. nov. A new genus, Archboldiceras, is proposed to accommodate the Australian species Uraloceras lobulatum and U. whitehousei. Species of the genus Sverdrupites Nassichuk, 1970 are described based on new material from the Volga-Urals Region. The new species S. bogoslovskayae from the Gerkinskaya Formation of Novaya Zemlya previously identified by M.F. Bogoslovskaya as S. amundseni is described. © Pleiades Publishing, Ltd. 2007.