Resurrection of the sixgill shark Hexanchus vitulus Springer & Waller, 1969 (Hexanchiformes, Hexanchidae), with comments on its distribution in the northwest Atlantic Ocean

@article{DalyEngel2018ResurrectionOT,
  title={Resurrection of the sixgill shark Hexanchus vitulus Springer \& Waller, 1969 (Hexanchiformes, Hexanchidae), with comments on its distribution in the northwest Atlantic Ocean},
  author={Toby S Daly-Engel and Ivy E. Baremore and R. Dean Grubbs and Simon J. B. Gulak and Rachel T. Graham and Michael P. Enzenauer},
  journal={Marine Biodiversity},
  year={2018},
  volume={49},
  pages={759-768}
}
The sixgill sharks of the genus Hexanchus (Hexanchiformes, Hexanchidae) are large, rarely encountered deep-sea sharks, thought to comprise just two species: the bluntnose sixgill Hexanchus griseus (Bonaterre, 1788) and the bigeye sixgill Hexanchus nakamurai (Teng, 1962). Their distribution is putatively worldwide in tropical and temperate waters, but many verified records for these species are lacking, and misidentification is common. Taxonomic uncertainty has long surrounded H. nakamurai in… 
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