Phylogeny of the Permian family Metalegoceratidae (Goniatitida, Ammonoidea)

The paper discusses the evolution of the Permian ammonoid family Metalegoceratidae, and a new phylogenetic reconstruction is proposed. Three subfamilies are recognized in this family: Metalegoceratinae Plummer et Scott, 1937; Pericycloceratinae Zhao et Zheng, 1977; and Eothinitinae Ruzhencev, 1956. The genus Metalegoceras Schindewolf, 1931 is subdivided into three subgenera: Metalegoceras s. str., Mesometalegoceras subgen. nov., and Artimetalegoceras subgen. nov. Five species of the endemic South Chinese metalegoceratids are described: Pseudometalegoceras shangraoense (Zhao et Zheng, 1977), P. liratum (Zhao et Zheng, 1977), P. platyventrum (Zhao et Zheng, 1977), P. spirale (Zhao et Zheng, 1977), and Pericycloceras costatum (Zhao et Zheng, 1977).