Dentition of etmopterid shark Miroscyllium (Squaliformes) with comments on the fossil record of lanternsharks

Faculty of Fisheries, Hokkaido University, Sapporo, Hokkaido, Japan
Cybium: international journal of ichthyology (Impact Factor: 0.58). 12/2006; 30(4):305-312.


Although modern lantern sharks (Etmopteridae, Squaliformes) are taxonomically diverse, their phylogenetic
relationships remain unclear. Numerous fossil etmopterids have been recently discovered, and their geologic occurrences are reviewed here. The dentition of the rare recent etmopterid M i ro s c y l l i u m s h e i k o i is described. The species shows peculiar ontogenetic changes in the morphology of lower and upper teeth, and allows to assign some fossil material described as Centroscyllium by Ledoux (1972) to Miroscyllium. Moreover, the presence, in Miroscyllium sheikoi, of a morphological transitional dental type between E t m o p t e ru s and C e n t ro s c y l l i u m, and its discovery in the fossil record allow to
propose an alternative way to contribute to the phylogenetic frameworks.

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