新疆南部早二叠世美羊齿类的发现

ON THE OCCURRENCE OF CALLIPTERIDS IN THEEARLY PERMIAN FROM SOUTH XINJIANG

保存良好的Autunia conferta.和Dichophyllum flabellifera近来在新疆塔里木盆地西北缘下二叠统上部的发现,是在塔里木盆地的首次记录.这两个种以前曾被归于Callipteris属内,后来Kerp指出该属的属名有问题,便与Haubold提出了形态属Callipteris的重新划分方案,这一方案笔者表示完全同意.A.conferta是欧美植物群中早二叠世常见分子,在中欧的少数地点亦见于上石炭统上部,在中国则极少发现,仅见报道于河北开平赵各庄群上部和山西太原下石盒子组.D.flabellifera是欧美植物群中的另一早二叠分子,在西欧和北美的上石炭统上部亦见少数先驱分子,在华夏植物群中从未发现过.本文记载为其在国内首次记录.上述发现在古植物地理上具有一定意义.

Fine specimens of Autunia conferta (Sternb.) Kcrp and Dichophyllum flabellifera (Weiss ) Kerp et Haubold have been obtained from the upper Lower Permian of northwestern Tarim Basin, Xinjiang, China and recorded for the first time in the Basin. Both species had been included in the genus Callipteris, before the validity of the generic name was doubted by Dr. Kerp. A reclassific ation of the form-genus Callipteris has been proposed by Kerp ,and Haubold, with which the writers are in complete accord. A. conferta is one of the most common species in the Early Permian Euramer-lan Flora, with sporidic occurrence in the upper Upper Carboniferous of Central Europe, has scarcely been found in China. It has been known from the upper part of Chaokochwang Fm. of Kaiping Basin, Heibei ani Lower Shihhotse Fm. of Tai-yuan, Shanxi. only. D. flabellata is another Euramerian Early Permian fossil , with a few forenunner in the upper Upper Carboniferous of West Europe and North America. It has never been found in the Cathaysian flora and is recorded here for the first time in China. The recent finding of these two species is considered to be of certain palaegeographical interest, which will be discussed in full length with a thorough study of the fossil assemblage in a forthcoming paper.