Eohiodon roseigroup is extinct

Guo-Qing Li and Mark V. H. Wilson
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Containing group: Eohiodon


†Eohiodon rosei (Hussakof) was first found in the Eocene Tranquille beds, near Red Point on Kamloops Lake. The holotype of this species is deposited in the collection of the Canadian Museum of Nature, Ottawa, Canada. Originally described in the genus Leuciscus (family Cyprinidae) by Hussakof (1916), it was transferred to the family Hiodontidae and made the type species of the new genus †Eohiodon by Cavender (1966). Specimens have since been found in the Horsefly beds near Horsefly, and the Allenby Formation near Princeton, British Columbia, Canada (Wilson 1977, 1978; Li, Wilson, and Grande, 1997). All known occurrences are of Eocene age.


†Eohiodon rosei differs from †E. woodruffi in having:

  1. A premaxillary bone with a relatively higher ascending process.
  2. A posteriorly excavated but dorsally convex operclar bone.
  3. Total vertebrae = 44-47 (Precaudal vertebrae 22-23, Caudal vertebrae 22-24).
  4. Principal dorsal-fin rays = 11-13.
  5. Dorsal pterygiophores = 13-14.
  6. Principal anal-fin rays = 15-18.
  7. Anal-fin pterygiophores = 16-18.


Cavender, T. 1966. Systematic position of the North American Eocene fish, "Leuciscus" rosei Hussakof. Copeia, 1966:311-320.

Hussakof, L. 1916. A new cyprinid fish Leuciscus rosei from the Miocene of British Columbia. American Journal of Science, 42:18-20.

Li G.-Q. Mark V. H. Wilson, and L. Grande. 1997. Review of Eohiodon (Teleostei: Osteoglossomorpha) from western North America, with a phylogenetic reassessment of Hiodontidae. Journal of PALEONTOLOGY, 71: 1109-1124.

Wilson, M. V. H. 1977. Middle Eocene freshwater fishes from British Columbia. Life Sciences Contributions, Royal Ontario Museum, 113:1-61.

Wilson, M. V. H. 1978. Eohiodon woodruffi n. sp. (Teleostei, Hiodontidae) from the middle Eocene Klondike Mountain Formation near Republic, Washington. Canadian Journal of Earth Sciences, 15:679-686.

Title Illustrations
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Scientific Name Eohiodon rosei
Location Horsefly beds, British Columbia, Canada
Specimen Condition Fossil
Size total length of 103mm
Copyright © 1998 Guo-Qing Li and Mark V. H. Wilson
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Chinese Academy of Sciences, Beijing , China

University of Alberta, Edmonton, Alberta, Canada

Correspondence regarding this page should be directed to Guo-Qing Li at and Mark V. H. Wilson at

All Rights Reserved.

Citing this page:

Li, Guo-Qing and Mark V. H. Wilson. 1998. Eohiodon rosei. Version 01 January 1998. in The Tree of Life Web Project,

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