论中国二叠纪四射珊瑚Liangshanophyllum

DISCUSSION ON PERMIAN RUGUSE CORAL LIANGSHANOPHYLLUM IN CHINA

迄今只报道于我国的梁山珊瑚Liangshanophyllum,以复中柱较小且简单、横板带宽、横板多水平或稍倾的特征区别于卫根珊瑚Waagenophyllum。本文对两属各种的复中柱大小(占体径比值)进行数据统计和差异性分析,结果表明在这一特征上,两属没有显著差异;定性分析复中柱简繁、横板带宽窄和水平横板发育程度,表明这些特征没有高于种一级的分类意义。结合其他的相关研究成果,建议废除Liangshanophyllum一属(亚属)。

The classified relationship between the genera Waagenophyllum and Liangshanophyllum has been controversial since Liangshanoplyllum was first described and established as a subgenus by Tseng(1949).Some researchers regard Liangshanophyllum as a genus or a synonym of Waagenophyllum.Based on the previous studies,Liangshanophyllum differs from Waagenophyllum in having a small and simplex axial column,wider tabularium and more horizontal tabulae.The diameter of corallite and the size of axial column of 29 species(include 1 subspecies)of Liangshanophyllum and 21 species of Waagenophyllum were calculated in this paper.The relationship between ratio of axial column diameter to corallite diameter and percentage of the species of Liangshanophyllum and Waagenophyllum are shown as below:Liangshanophyllum:≥1/3,4 species(occupying 14%);1/3-1/4(include 1/4),11 species(occupying 38%);1/4–1/5(include 1/5),7 species(occupying 24%),<1/5,7 species(occupying 24%);Waagenophyllum:≥1/3,4 species(occupying 18%);1/3–1/4(include 1/4),10 species(occupying 45%);1/4–1/5(include 1/5),5 species(occupying23%),<1/5,3 species(occupying 14%).The ratio of axial column diameter to corallite diameter of W.minutum is 1/5–1/3.It calculates once in 1/3–1/4 and 1/4–1/5.The result shows that there is no obvious difference between the ratio of axial column diameter to corallite diameter of the species belonging to Liangshanophyllum and Waagenophyllum.Qualitative analysis of the complexity of axial structure and tabularium width also shows that the species of Liangshanophyllum and Waagenophyllum have no difference higher than genus level.Clinotabulae and horizontal tabulae alternately developed in some species such as Liangshanophyllum interomurum.So the development of horizontal tabulae should be considered as intraspecific variation.On this basis,combined with other research results,such as cladistic analysis of some species of Waagenophyllum,this paper suggests that Liangshanoplyllum is a synonym of Waagenophyllum.