贵州省惠水县王佑中泥盆世晚期的四射珊瑚(二)

GIVETIAN(DEVONIAN) RUGOSE CORALS FROM WANGYOU, HUISHUI, GUIZHOU(2)

贵州省惠水县王佑镇至翁赖村一带出露中泥盆统上部浅海底栖相翁赖组(新名),该组以陆源碎屑沉积居多、沉积厚度较大、群体珊瑚很少而单体珊瑚却比较发育为主要特征。其中,翁赖组上部层位与贵州独山剖面独山组鸡窝寨段相当,时代为中泥盆世吉维特期的晚期(late Givetian)。翁赖组上部之底非常特征的中华海绵珊瑚化石(Sinospongophyllum)与中泥盆统上部吉维特阶标准的腕足类化石鸮头贝(Stringocephalus)共栖。该属与华南地区中泥盆世晚期标准的内板珊瑚(Endophyllum)的内部骨骼构造非常相似,仅外部形态不同。在华南地区,内板珊瑚和中华海绵珊瑚的层位非常稳定,大致相当于吉维特阶的下varcus带。文中描述翁赖组上部四射珊瑚8属13种,包括Calceola intermediata inflata Yoh,,Cystiphylloides kwangsiense Yoh,C.secundus(Goldfuss),C.sp.,Paramixogonaria wangyouensis sp.nov.,Grypophyllum?sp.,Mictophyllum shawoziense He,M.sp.,Sinospongophyllum planotabulatum Yoh,Temnophyllum waltheri Yoh,T.poshiense Wang,T.complicatum Wang和Thamnophyllum crassum(Kong)等。它们与华南其他地区以及亚洲、欧洲、北非、澳大利亚和北美西部的同期分子都有十分密切的关系,同属于老世界生物地理大区(Old World Realm)。

The Givetian(late Middle Devonian)Wenglai Formation at Wangyou and Wenglai areas,Guizhou Province,South China is characterized by the predominance of terrestrial clasts,such as argillaceous sandstone and sandy mudstone,and abundant solitary rugose corals but very few colonial forms.The present study describes the rugose corals from the upper part of Wenglai Formation,following our previous paper on its lower part.The upper part of Wenglai Formation correlates to the Jiwozhai member in Dushan County,Guizhou Province,and is late Givetian in age,which is determined by the occurrence of the solitary rugose coral Sinospongophyllum and typical Givetian brachiopod Stringocephalus at the bottom of the upper part of the Wenglai Formation.The skeletal structure of this Sinospongophyllum is very similar to that of typical Givetian rugose coral Endophyllum,but differs in external forms.Both Sinospongophyllum and Endophyllum occur roughly in the conodont lower varcus Biozone.In this study,we describe 13 species belonging to 8 genera of rugose corals.They are:Calceola intermediata inflata Yoh,Cystiphylloides kwangsiense Yoh,C.secundus(Goldfuss),C.sp.,Paramixogonaria wangyouensis sp.nov.,Grypophyllum?sp.,Mictophyllum shawoziense He,M.sp.,Sinospongophyllum planotabulatum Yoh,Temnophyllum waltheri Yoh,T.poshiense Wang,T.complicatum Wang and Thamnophyllum crassum(Kong).Most of these species share close affinity with their contemporary species occurring from the other regions of South China,as well as from the other regions of Asia,and from Europe,North Africa,Australia and the western part of the North America,indicating that they all belong to the Old World Realm.