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Updated: Jul 12, 2026

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In Situ Hybridization in Zebrafish Larvae and Juveniles during Mesonephros Development
Published on: August 13, 2021
First fossil hagfish (myxinoidea): a record from the pennsylvanian of illinois
Abstract:
A fossil hagfish (Myxinoidea), a new genus from the Pennsylvanian, shows tentacles, structures of the head skeleton and internal organs. No other fossils of this group have been reported. Although this new hagfish differs from living forms in position of the gills, feeding apparatus, and relatively well developed eyes, it is quite similar to its recent relatives. Thus, hagfishes have a long, conservative geological history. Cladograms showing myxinoids as a sister group to the vertebrates are supported.
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