Histology of the first fish

M.P. Smith; I.J. Sansom; J.E. Repetski

doi:10.1038/380702a0

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Histology of the first fish

M.P. Smith·I.J. Sansom·J.E. Repetski

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Abstract

The first description of Anatolepis Bockelie & Fortey was from early Ordovician sediments of Ny Friesland, Spitsbergen 1,2 , but the genus is now known from many localities in North America and Greenland, ranging in age from the Late Cambrian period to the Early Ordovician 3–6 . Although initially interpreted as an agnathan fish 2,3 that predated other representatives 7 , this has been widely disputed because the available histological data were unconvincing 6,8–10 and the scales fell outside the known morpho-logical range of other accepted early vertebrates 9–11 . Further doubt was cast upon the vertebrate affinity of Anatolepis when specimens from East Greenland were interpreted as the cuticular fragments of aglaspid arthropods 6 , although this interpretation has also been refuted 12 . Here we report on the morphology and histology of large collections of Anatolepis , and demonstrate the presence of dentine, a tissue unique to vertebrates, confirming that the taxon is both a vertebrate and the oldest known fish.

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M.P. Smith, I.J. Sansom, J.E. Repetski. 1996. Histology of the first fish. https://doi.org/10.1038/380702a0

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