云南首次发现晚侏罗世马门溪龙化石

Discovery of Late Jurassic Mamenchisaurus in Yunnan, southwestern China

侏罗纪在全球范围内属于重要的产煤期,然而此时云南、四川中—南部没有煤系出现,反而发育了一套独特的“红色岩系”。在这样的环境中生活并繁盛着蜥脚亚目等形形色色的恐龙,与中国北部、东部地区的恐龙类群有明显的差异。马门溪龙在中国主要发现于四川,最近在云南侏罗纪“红层”中发现云南马门溪龙(新种)尚属首次,再次证实禄丰一带存在上侏罗统。该化石产于禄丰川街盆地老长箐-大尖峰剖面,在其下部地层中还分别产出代表中侏罗世的川街龙和早侏罗世的禄丰龙化石。能在同一完整地层剖面上见到不同时段早、中、晚侏罗世3套恐龙动物群,这在国内外都是罕见的。

Although the Jurassic is a major coal-making period worldwide, no coal measures appear in Yunnan and central and southern Sichuan. Instead, there occur a unique 'red rock series'. In such an environment various types of dinosaurs such as Sauropoda lived and flourished, which are quite different from dinosaur faunas found in northern and eastern China. Mamenchisaurus is mainly found in Sichuan and recently Mamenchisaurus yunnanensis sp. nov. has been found for the first time in the Jurassic 'red beds' in Yunnan. This discovery strongly supports the view that Upper Jurassic strata are present in the Lufeng basin, Yunnan. The new fossil occurs in the Laochangqing-Dajianfeng section in the Chuanjie basin, Lufeng. In the lower part of the section there occur the Middle Jurassic Chuanjiesaurus and Early Jurassic Lufengosauru. The most important significance of this new discovery is that three succeeding dinosaur faunas that represent the Early, Middle and Late Jurassic ages respectively are found in one section, which is also rarely seen around the world.