Article: Cardioceratid and kosmoceratid ammonites from the Callovian of Yorkshire
J. H. Callomon and J. K. Wright
New stratigraphic evidence and systematic revision, including the designation of types where necessary, establish unambiguously the definitions and precise ages of a number of classical species of ammonites which, although in part rare in this country, are of great importance in understanding the evolution of the Boreal and Sub-boreal families Cardioceratidae and Kosmoceratidae. They include Pseudocadoceras boreale Buckman, 1918, Chamoussetia funifera (Phillips, 1829), Chamoussetia phillipsi = nom. nov. pro Ammonites lenticularis Phillips, 1829, non Young and Bird 1828, Longaeviceras placenta (Leckenby, 1859), Quenstedtocerasflexicostatum (Phillips, 1829) and Kosmoceras rowlstonense (Young and Bird, 1822). Five new specific names are introduced: Chamoussetia phillipsi nom. nov., C. buckmani and C. saratovensis spp. nov., Pseudocadoceras grewingki whithami subsp. nov., and Longaeviceras polonicum sp. nov.