Computed tomography scanning as a tool for linking the skeletal and otolith-based fossil records of teleost fishes

Micro-computed tomography scanning (µCT scanning) now represents a standard tool for non-destructive study of internal or concealed structure in fossils. Here we report on otoliths found in situ during routine µCT scanning of three-dimensionally preserved skulls of Palaeogene and Cretaceous fishes. Comparisons are made with isolated otolith-based taxa in order to attempt correlations between the body fossil and otolith fossil records. In situ otoliths previously extracted mechanically from specimens of Apogon macrolepis and Dentex laekeniensis match our µCT models. In some cases, we find a high degree of congruence between previously independent taxonomic placements for otolith and skeletal remains (Rhinocephalus, Osmeroides, Hoplopteryx). Unexpectedly, in situ otoliths of the aulopiform Apateodus match isolated otoliths of Late Cretaceous age previously interpreted as belonging to gempylids, a group of percomorph fishes that do not appear in the body fossil record until the Palaeogene....

显微计算机断层扫描（micro-computed tomography scanning，简称µCT扫描）如今已成为无损研究化石内部或隐蔽结构的标准实验手段。本次研究报道了在对古近纪与白垩纪鱼类的三维保存头骨开展常规µCT扫描时原位发现的耳石（otolith）。研究将其与以分离耳石为依据的类群进行比对，以期建立躯体化石记录与耳石化石记录之间的关联。此前通过机械方式从大鳞天竺鲷（Apogon macrolepis）和Dentex laekeniensis的标本中提取的原位耳石，与本次研究的µCT扫描模型高度吻合。在部分案例中，耳石与骨骼遗骸此前独立得出的分类学归属存在高度一致性（如Rhinocephalus、Osmeroides、Hoplopteryx）。出乎意料的是，仙女鱼目（Aulopiformes）Apateodus属的原位耳石，与此前被认为属于蛇鲭科（Gempylidae）的晚白垩世分离耳石相匹配；而该类鲈形总目（percomorph）鱼类的躯体化石记录直至古近纪才出现……