Asineops (Greek for "donkey-faced")[1] is an enigmatic genus of extinct freshwater ray-finned fish from the Eocene. It is the only member of the family Asineopidae and contains a single species, A. squamifrons, from the famous Green River Formation of Colorado, Wyoming, and Utah. It was described by Edward Drinker Cope in 1870.[2]

Asineops
Temporal range: Early Eocene, 53.5–48.5 Ma
Asineops squamifrons
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Percopsiformes (?)
Family: Asineopidae
Cope, 1877
Genus: Asineops
Cope, 1870
Species:
A. squamifrons
Binomial name
Asineops squamifrons
Cope, 1870
Synonyms
  • Asineops pauciradiatus Cope, 1877

Asineops is known from all three prehistoric lakes that would eventually become the Green River Formation, although it is only common in the former Lake Gosiute's deposits. It is extremely rare in the famous Fossil Lake deposits.[1]

Some sources, including Cope, considered it allied with the pirate perch and classified Asineops with it in the family Aphredoderidae. However, more recent analysis indicates that it lacks many of the traits of that family. Other sources still consider it a percopsisform and related to the sympatric percopsiform Erismatopterus.[1][2][3] However, an affinity to the Polymixiiformes or Perciformes has also been suggested. Little further research has been done of its affinity, and it is thus considered to be an indeterminate acanthomorph.[1]

References

edit
  1. ^ a b c d Grande, Lance (2001), Gunnell, Gregg F. (ed.), "An Updated Review of the Fish Faunas From the Green River Formation, the World's Most Productive Freshwater Lagerstätten", Eocene Biodiversity: Unusual Occurrences and Rarely Sampled Habitats, Topics in Geobiology, Boston, MA: Springer US, pp. 1–38, doi:10.1007/978-1-4615-1271-4_1, ISBN 978-1-4615-1271-4, retrieved 2024-02-25
  2. ^ a b "PBDB". Paleobiology Database. Retrieved 2024-02-25.
  3. ^ "The Geological History of Fossil Butte National Monument and Fossil Basin, by Paul O. McGrew and Michael Casilliano". www.gutenberg.org. Retrieved 2024-02-25.