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晚三叠世台形牙形刺分子属有Ｐａｒａｇｏｎｄｏｌｅｌｌａ，Ｍｅｔａｐｏｌｙｇｎａｔｈｕｓ，Ａｎｃｙｒｏｇｏｎｄｏｌｅｌｌａ和Ｅｐｉｇｏｎｄｏｌｅｌｌａ。这些属都源于中三叠世，可能来自同一根源──Ｎｅｏｇｏｎｄｏｌｅｌｌａ，但有两个不同的演化趋向。本文认为这些台形分子分类演化上最重要的形态特征仅是一些微小的变化，如齿台下方后龙脊─基部附着面，基穴和环台面的细部变化。对Ｍｅｔａｐｏｌｙｇｎａｔｈｕｓ属台形分子的发展演化作了专门讨论，指出了晚三叠世台形牙形刺分子的演化系统。
Late Triassic toxoid molecules are Paragondolella, Metapolygnathus, Ancyrogondolella and Epigondolella. These belong to the Middle Triassic, probably from the same source - Neogondolella, but with two different evolutionary trends. This paper argues that the most important morphological characteristics of the classification and evolution of these table-shaped molecules are only slight changes, such as the changes of the detail of the ridge-base attachment surface, basement and ring mesa after the gear table. Metapolygnathus genesis and development of platform-shaped molecules made a special discussion, pointed out that the Late Triassic toothache molecules evolution system.