Baptanodon is an ichthyosaur of the Late Jurassic period (160-156 million years ago), named for its supposed lack of teeth (although teeth of this genus have since been discovered).[1] It had a graceful 3.5 m (11 ft) long dolphin-shaped body, and its jaws were well adapted for catching squid.[2] Major fossil finds of this genus have been recorded in North America. The type species, Sauranodon natans, was originally included under Sauranodon in 1879,[3] but this name was preoccupied.

Baptanodon
Temporal range: Late Jurassic, 160–156 Ma
Holotype skull of B. natans
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Order: Ichthyosauria
Family: Ophthalmosauridae
Subfamily: Ophthalmosaurinae
Genus: Baptanodon
Marsh, 1880
Type species
Baptanodon natans
Marsh, 1880
Synonyms
  • Ophthalmosaurus natans Marsh, 1879
  • Sauranodon Marsh, 1879 (preoccupied)
  • Microdontosaurus Gilmore, 1902

Discovery and species

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Baptanodon is a replacement name for Sauranodon applied to ichthyosaur material in 1879[3] and was moved to its own genus Baptanodon in 1880 when Sauranodon was found to be preoccupied.[4] Baptanodon was considered a junior synonym of Ophthalmosaurus by Maisch & Matzke (2000).[5] However, cladistic analyses published in the 2010s indicate that Baptanodon is not congeneric with Ophthalmosaurus icenicus.[6][7][8]

Classification

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The cladogram below follows Fischer et al. 2012.[7]

Thunnosauria 

Palaeobiology

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Fossils of Baptanodon have been found in the Oxfordian-age Sundance Formation of Wyoming, which also has yielded fossils of the cryptoclidids Tatenectes and Pantosaurus, and the pliosaurid Megalneusaurus.[4][10]

See also

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References

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  1. ^ Gilmore, C. W. (1902). "Discovery of teeth in Baptanodon, an ichthyosaurian from the Jurassic of Wyoming". Science. 16 (414): 913–914. Bibcode:1902Sci....16..913G. doi:10.1126/science.16.414.913. PMID 17756122.
  2. ^ Massare, J.A.; Wahl, W.R.; Ross, M.; Connely, M.V. (2014). "Palaeoecology of the marine reptiles of the Redwater Shale Member of the Sundance Formation (Jurassic) of central Wyoming, USA". Geological Magazine. 151 (1): 167–182. doi:10.1017/S0016756813000472.
  3. ^ a b O. C. Marsh. 1879. A new order of extinct reptiles (Sauranodonta), from the Jurassic Formation of the Rocky Mountains. The American Journal of Science and Arts, series 3
  4. ^ a b Marsh, O. C., 1880, Note on Sauranodon: American Journal of Science, 3rd series, v. 19, n. 4, p. 491.
  5. ^ Maisch MW, Matzke AT. 2000. The Ichthyosauria. Stuttgarter Beiträge zur Naturkunde, Serie B (Geologie und Paläontologie) 298: 1-159.
  6. ^ Patrick S. Druckenmiller; Erin E. Maxwell (2010). "A new Lower Cretaceous (lower Albian) ichthyosaur genus from the Clearwater Formation, Alberta, Canada". Canadian Journal of Earth Sciences. 47 (8): 1037–1053. Bibcode:2010CaJES..47.1037D. doi:10.1139/E10-028.
  7. ^ a b Valentin Fischer; et al. (2012). "New Ophthalmosaurid Ichthyosaurs from the European Lower Cretaceous Demonstrate Extensive Ichthyosaur Survival across the Jurassic–Cretaceous Boundary". PLOS ONE. 7 (1): e29234. Bibcode:2012PLoSO...729234F. doi:10.1371/journal.pone.0029234. PMC 3250416. PMID 22235274.
  8. ^ Ilaria Paparella; Erin E. Maxwell; Angelo Cipriani; Scilla Roncacè; Michael W. Caldwell (2017). "The first ophthalmosaurid ichthyosaur from the Upper Jurassic of the Umbrian–Marchean Apennines (Marche, Central Italy)". Geological Magazine. 154 (4): 837–858. doi:10.1017/S0016756816000455.
  9. ^ Arkhangel’sky, M. S., 1998, On the Ichthyosaurian Genus Platypterygius: Palaeontological Journal, v. 32, n. 6, p. 611-615.
  10. ^ Marsh, O. C., 1895, The Reptilia of the Baptanodon Beds: American Journal of Science, 3rd series, v. 34., n. 299, p. 405-406.