Middle Permian rugose corals from Laibin, Guangxi, South China

The Middle Permian Chihsia and Maokou formations in Laibin, central Guangxi , South China contain 19 rugose coral species' of these taxa, Lophocarinoph yllum sandoi, Asserculinia solida, and Innixiphyllum wuae are new. Innixiph yllum represents a new genus characterized by contratingent minor septa. Te n species are reviewed and described in detail, and the diagnoses of three of these species, Allotropiophyllum heteroseptatum (Grabau. 1928), Lophocar inophyllum taihuense (Yan and Chen, 1982), and Ipciphyllum regulare (Wu, 19 63), are newly emended. The morphological variation and ontogenetic changes of the solitary, nondissepimented species are particularly emphasized. Six additional taxa are described and illustrated but are left in open nomencl ature. The corals from Laibin are typically Tethyan. Four biostratigraphic assembl ages are recognized: an assemblage of massive corals in the upper Chihsia F ormation represented by Polythecalis longliensis; an assemblage of small so litary and nondissepimented corals in the lower Maokou Formation. dominated by species of Allotropiophyllum, Innixiphyllum and Lophocarinophyllum; an assemblage of mixed massive colonial and small solitary corals in the middl e Maokou Formation. characterized by Ipciphyllum regulare; and an assemblag e of solitary nondissepimented corals in the uppermost Maokou Formation, ch aracterized by Ufimia elongata. These assemblages correspond well to those from other areas of South China. In Laibin, only two rugose taxa. Amplexoca rinia sp. and Paracaninia minor, occur in the basal part of the Wuchiaping Formation of Lopingian age.