Evolution of Rudist revealed by their shell micro sturucture

鲁德类是一类主要生活在中生代，特别是侏罗纪和白垩纪之间的具有特殊壳形的无柄双壳类动物。这群人在那段时间里享受着他们的繁荣。它们的化石在碳酸盐岩台地环境中大量出现，是重要的有机构造元素。该群在晚侏罗世作为一个科出现，然后在白垩纪时期分化为6个科，包括100个属。在本研究中，研究了基团的特殊形态和特殊的壳结构。为此，研究人员检查了维也纳大学和奥地利维也纳自然历史博物馆的材料。此外，在德国、奥地利、斯洛文尼亚以及意大利北部，人们还访问和检查了几个重要的ruddist化石地点。最后，由Cestari， R.和Sartorio， D.（1995）撰写的关于这一主题的经典教科书《浅海陆域的Rudists and facies of Periadriatic Domain》（由Agip， s.p.a.， S. Donanto Milanese出版）被翻译成日文，以刺激日本古生物学家对这一主题的研究。

Rudists are a group of mainly sessile bivalves with peculiar shell forms, which lived in the Mesozoic Era arid especially between Jurassic and Cretaceous Periods in so called Thethysan Region. The group enjoyed their prosperity during the time. Their fossils occur abundantly from carbonate plat-form environments, and were an important element as organic builder. The group appeared as one family in the late Jurassic, then during the Cretaceous Period it diversified into 6 families including 100 genera.In the present study, the peculiar morphology of the group as well as peculiar shell structure was investigated.To do so material in Vienna University as well as in Natural History Museum, Vienna, Austria was examined. Also several important localities of the Rudist fossils was visited and examined in Germany, Austria, and Slovenia as well as northern Italy.Finally a classic Text book on this theme, "Rudists and facies of the Periadriatic Domain" written by Cestari, R. and Sartorio, D. (1995) (published by Agip, S.p.A., S. Donanto Milanese) was translated into Japanese to stimulate the study on this topic by Japanese paleontologists.