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从晶体类型到釉质结构4个不同的微观结构等级详细描述了安徽潜山中古新世胡氏敏兽的门齿釉质微观结构。样品取自胡氏敏兽正型标本的上门齿后端。该门齿最外层为一极薄的无釉柱层,外层为放射状釉柱层,内层为具多层的施氏明暗带。施氏明暗带的单带厚度变化较大,倾斜度相对较小,带间无明显的过渡带,釉柱的横切面为不规则圆形,釉柱间质较厚,外层间质晶体平行于釉柱长轴。这些特征与啮齿类中的散系施氏明暗带极为相似。同时还发现有缎状的釉柱中缝和聚敛型的晶体间断分布在釉质的不同部位,而这些特征一般被认为是啮形类,甚至是哺乳动物的较为原始特征。与其他已报道的基干啮型类对比,胡氏敏兽的门齿釉质代表了啮形类中已知最早的双层似散系釉质类型,具有更多的较原始特征,为啮形类门齿釉质研究提供了更多的形态学信息,并显示啮形类的演化可能远比现在认知的复杂。
From the crystal type to the enamel structure at four different microstructure levels, the microscopic structure of the incisor enamel of the Middle Paleocene Hu Minxian in the buried hill of Anhui Province is described in detail. The sample was taken from the back end of the front tooth of the positive specimen of Hu Shi Min Bei. The incisor outermost layer is an extremely thin unglazed layer, the outer layer is a radial glaze layer, the inner layer is a multi-layer Shihlin dark. The thickness of single band in Schist series is larger, the inclination is relatively smaller, there is no obvious transition zone between the bands, and the cross section of the glaze column is irregularly circular. The interlayer of the glaze column is thick and the outer layers of the intergranular crystals are parallel In the long axis of the glaze. These features are very similar to the scattered Schind Stable light in rodents. At the same time, it was also found that satin-like glaze seams and convergent crystals were discontinuously distributed in different parts of the enamel, and these features are generally considered as the primitive features of the rodents and even mammals. In contrast to other reported stems, the enamel of Huntsman represents the earliest known double-layered, interspersed, enamel type of the genus Racia, with more of the more primitive features of the genus Research provides more morphological information and shows that the evolution of the rodent class can be far more complicated than it is now.