武汉地区三种大戟科化石木的研究  

STUDIES ON THREE FOSSIL WOODS OF EUPHORBIACEAE EXCAVATED FROM WUHAN AREA

作　　者：杨家驹[1] 齐国凡[1] 徐瑞瑚 杨礼茂 

机构地区：[1]中国林业科学研究院木材工业研究所,湖北大学地理系

出　　处：《Acta Botanica Sinica》1998年第1期68-76,共9页Acta Botanica Sinica（植物学报：英文版）

基　　金：湖北省自然科学基金

摘　　要：研究了我国湖北省武汉市新洲县阳逻镇出土的大戟科树种的化石木，它们是武汉叶下珠（ＰｈｙｌｌａｎｔｈｕｓｗｕｈａｎｅｎｓｉｓＪ．Ｊ．Ｙａｎｇｓｐ．ｎｏｖ．）、武汉土密树（ＢｒｉｄｅｌｉａｗｕｈａｎｅｎｓｉｓＪ．Ｊ．Ｙａｎｇｓｐ．ｎｏｖ．）、重阳木（ＢｉｓｃｈｏｆｉａｐｏｌｙｃａｒｐａＡｉｒｙＳｈａｗ）。这些化石木的地质年代为晚第三纪（距今２０００～２５０万年）。根据林木生长条件和树种演化，晚第三纪时期当地的气候是炎热和潮湿的：１大戟科的叶下珠亚科现代树木主要分布于热带地区；２晚第三纪时，在武汉地区热带树种楸枫（Ｂ．ｊａｖａｎｉｃａＢｌ．）与现代亚热带树种重阳木并存，现代树种重阳木系具半散孔趋势的散孔材，而晚第三纪时武汉地区的化石木无半散孔趋势，反映了重阳木这个树种演化；３该地区化石木群中还有热带树种顶果木（ＡｃｒｏｃａｒｐｕｓｆｒａｘｉｎｉｆｏｌｉａＡｒｎ．ｅｘＷｉｇｈｔ）和海南红豆（ＯｒｍｏｓｉａｐｉｎｎａｔａＭｅｒ．）。A group of angiosperm fossil woods from the Late Tertiary rocks were excavated in the northern part of Yanglou Town, Xinzhou County,the City of Wuhan,Hubei Province. The angiosperm fossil wood in China was discovered and studied for the first record. Three fossil woods have been identified to be Phyllanthus wuhanensis J.J.Yang sp.nov.Bridelia wuhanensis J.J.Yang sp.nov. and Bischofia polycarpa AiryShaw of the Phyllanthoideae. A group belonging to Phyllanthoideae of the Euphorbiaceae,and the more scorching and humid climate in Wuhan area at the ancient time than it is recently deduced from: 1.The habitat of the modern Phyllanthoideae trees are mainly in the tropical zone; 2.Besides the three species of Phyllanthoideae the previously reported Acrocarpus fraxinifolius Arn.ex Wight of Mimosaceae and Ormosia pinnata Merr. of Papilionaceae which are modern tropical tree species,also were included in the fossil wood group; 3.The Bischofia polycarpa AiryShaw recently growing in Wuhan area in the subtropical zone,was included in the fossil wood group with previously reported Bischofia javanica Bl., a modern tropical tree species which has disappeared in the subtropical zone. The modern B. polycarpa AiryShaw is a diffusewood tending to become semidiffusewood while no such tendency was found in its fossil wood,showing the tree evolution from tropical tree species to subtropical one,for the tropical species tend to have diffusewood.

关 键 词：被子植物 化石木 大戟科 

分 类 号：Q914.21[天文地球—古生物学与地层学] Q914.88[生物学—古生物学]