Onchopristis is an extinct genus of sclerorhynchoid from the Cretaceous of North Africa, Europe, and North America. Its name is derived from the Ancient Greek ónkos (ὄγκος, 'barb') and prístis (πρίστις, 'saw' or 'sawfish').[2] It contains two valid species, O. numida and O. dunklei, though some researchers argue that both may be considered a single taxon with variation in morphology caused by a wide geographical range.[12] Specimens of Onchopristis have been discovered in coastal and fluvial deposits dated from the Barremian to the Cenomanian age,[13][1] making this genus one of the oldest and longest-lived sclerorhynchoid genera.

Onchopristis
Temporal range: Barremian–Cenomanian
Restoration of O. numida
Scientific classification
Kingdom:
Phylum:
Class:
Superorder:
Order:
Suborder:
Family:
Onchopristidae

Villalobos-Segura, Kriwet, Vullo, Stumpf, Ward, & Underwood, 2021[1]
Genus:
Onchopristis

Type species
Onchopristis numida
(Haug, 1905)[3]
Other species
  • Onchopristis dunklei
    McNulty & Slaughter, 1962[4]
Synonyms
Genus synonymy
    • Platyspondylus
      Haug, 1905
    • Onychopristis
      Jordan, 1923 (lapsus calami)[5]
    • Peyeria
      Weiler, 1935[6]
    • Sechmetia
      Werner, 1989[7]
    • Onchopristes
      Kirkland, 1996 (lapsus calami)[8]
    • Ochopristis
      Hunt, Santucci, & Kenworthy, 2006 (lapsus calami)[9]
Species synonymy
  • O. numida
      • Gigantichthys numidus
        Haug, 1905
      • Platyspondylus foureaui
        Haug, 1905
      • Squatina aegyptiaca
        Stromer, 1927[10]
      • Sechmetia aegyptiaca
        (Stromer, 1927)
      • Peyeria libyca
        Weiler, 1935
    O. dunklei
      • Onchopristis dunklei praecursor
        Thurmond, 1971[11]
      • Sechmetia cruciformis
        Werner, 1989

Description edit

Specimens of O. numida, IPUW 353500 and IGR 2818, suggest a length estimate of 2.94–4.25 m (9.6–13.9 ft) and 2.21–3.15 m (7.3–10.3 ft), respectively; such individuals would have weighed 70–150 kg (150–330 lb).[1] Like other sclerorhynchoids, it had a long rostrum with large denticles similar to sawfishes and sawsharks. This feature was convergently evolved and its closest living relatives are actually skates.[1] Isolated rostral denticles are the most common fossils of Onchopristis, but rostra, chondrocrania, jaws, oral teeth, vertebrae, and dermal denticles have also been found.[1][14]

Taxonomy edit

 
Rostral denticle of O. numida

Gigantichthys numidus was named by Émile Haug in 1905 for fragmentary rostral denticles from the Continental intercalaire of Algeria. Haug also named Platyspondylus foureaui for vertebrae from the same formation.[3] Articulated specimens have confirmed that the rostral denticles and vertebrae belong to the same species.[1][14] In 1917, Ernst Stromer named the new genus Onchopristis with "G". numidus as the type species.[2] Although the spelling "Onchopristis numidus" is commonly used, it is grammatically incorrect and has been emended to O. numida.[15]

Oral teeth from the Bahariya Formation of Egypt were named Squatina aegyptiaca by Stromer in 1927, and were later renamed as the separate genus Sechmetia by Christa Werner in 1989.[10][7] Again, articulated specimens confirmed that these teeth belong to O. numida.[1][14] In 1935, Wilhelm Weiler named Peyeria libyca for what he thought were sawfish rostral denticles from the Bahariya Formation.[6] An associated specimen of Ischyrhiza mira, a close relative of Onchopristis, indicates that "Peyeria" are actually dermal denticles from O. numida.[16]

A second valid species from the Woodbine Formation of Texas, Onchopristis dunklei, was named by Charles McNulty, Jr. and Bob Slaughter in 1962.[4] In 1971, John Thurmond named the subspecies O. dunklei praecursor, but it is probably not distinct from O. dunklei.[11][17] Rostral denticles from New Zealand formerly referred to "O. d. praecursor" have been reassigned to their own genus and species, Australopristis wiffeni.[18][12] An uncritical summary of 70 vertebrate taxa found in the Aguja Formation reports the presence of O. dunklei based on two fragmentary specimens, though the authors acknowledge the skepticism regarding the Campanian-Maastrichtian occurrence of this genus.[19] Subsequent studies have identified these specimens as Columbusia deblieuxi.[20][21]

References edit

  1. ^ a b c d e f g Villalobos-Segura, E.; Kriwet, J.; Vullo, R.; Stumpf, S.; Ward, D.J.; Underwood, C.J. (2021). "The skeletal remains of the euryhaline sclerorhynchoid †Onchopristis (Elasmobranchii) from the 'Mid'-Cretaceous and their palaeontological implications". Zoological Journal of the Linnean Society. 193 (2): 746–771. doi:10.1093/zoolinnean/zlaa166.
  2. ^ a b c Stromer, E. (1917). "Ergebnisse der Forschungreisen Prof. E. Stromers in den Wüsten Ägyptens. II. Wirbeltier-Reste der Baharîje-Stufe (unterstes Cenoman). 4. Die Säge des Pristiden Onchopristis numidus Haug sp. und über die Sägen der Sägehaie" (PDF). Abhandlungen der Königlich Bayerischen Akademie der Wissenschaften, Mathematisch-physikalische Klasse. 18 (8): 1–28.
  3. ^ a b Haug, E. (1905). "Paléontologie". In Foureau, F. (ed.). Documents scientifiques de la mission saharienne, mission Foureau-Lamy d'Alger au Congo par le Tchad. Fascicule 3. Paris: Masson. pp. 751–832.
  4. ^ a b McNulty, C.L. Jr.; Slaughter, B.H. (1962). "A new sawfish from the Woodbine Formation (Cretaceous) of Texas". Copeia. 1962 (4): 775–777. doi:10.2307/1440678. JSTOR 1440678.
  5. ^ Jordan, D.S. (1923). "A classification of fishes, including families and genera as far known". Stanford University Publications, University Series, Biological Sciences. 3 (2): 77–243. doi:10.5962/bhl.title.161386.
  6. ^ a b Weiler, W. (1935). "Ergebnisse der Forschungsreisen Prof. E. Stromers in den Wüsten Ägyptens. II. Wirbeltierreste der Baharîje-Stufe (unterstes Cenoman). 16. Neue Untersuchungen an den Fischresten" (PDF). Abhandlungen der Bayerischen Akademie der Wissenschaften, Mathematisch-naturwissenschaftliche Abteilung. 32: 1–57.
  7. ^ a b Werner, C. (1989). "Die Elasmobranchier-Fauna des Gebel Dist Member der Bahariya Formation (Obercenoman) der Oase Bahariya, Ägypten". Palaeo Ichthyologica. 5: 1–112.
  8. ^ Kirkland, J.I. (1996). "Paleontology of the Greenhorn cyclothem (Cretaceous: late Cenomanian to middle Turonian) at Black Mesa, northeastern Arizona". New Mexico Museum of Natural History and Science Bulletin. 9: 1–131.
  9. ^ Hunt, R.K.; Santucci, V.L.; Kenworthy, J. (2006). "A preliminary inventory of fossil fish from National Park Service units". New Mexico Museum of Natural History and Science Bulletin. 34: 63–69.
  10. ^ a b Stromer, E. (1927). "Ergebnisse der Forschungsreisen Prof. E. Stromers in den Wüsten Ägyptens. II. Wirbeltierreste der Baharîje-Stufe (unterstes Cenoman). 9. Die Plagiostomen mit einem Anhang über käno- und mesozoische Rückenflossenstacheln von Elasmobranchiern" (PDF). Abhandlungen der Bayerischen Akademie der Wissenschaften, Mathematisch-naturwissenschaftliche Abteilung. 31 (5): 1–64.
  11. ^ a b Thurmond, J.T. (1971). "Cartilaginous fishes of the Trinity Group and related rocks (Lower Cretaceous) of north central Texas" (PDF). Southeastern Geology. 13 (4): 207–227.
  12. ^ a b Martill, D.M.; Ibrahim, N. (2012). "Aberrant rostral teeth of the sawfish Onchopristis numidus from the Kem Kem beds (?early Late Cretaceous) of Morocco and a reappraisal of Onchopristis in New Zealand". Journal of African Earth Sciences. 64: 71–76. Bibcode:2012JAfES..64...71M. doi:10.1016/j.jafrearsci.2011.11.009.
  13. ^ Kriwet, J. (1999). "Neoselachier (Pisces, Elasmobranchii) aus der Unterkreide (unteres Barremium) von Galve und Alcaine (Spanien, Provinz Teruel)". Palaeo Ichthyologica. 9: 113–142.
  14. ^ a b c Dutheil, D.B.; Brito, P.M. (2009). "Articulated cranium of Onchopristis numidus (Sclerorhynchidae, Elasmobranchii) from the Kem Kem bed, Morocco". In Jalil, N.E. (ed.). 1st International Congress on North African Vertebrate Palaeontology. Program & Abstracts (PDF). Marrakesh. p. 58. Archived from the original (PDF) on 2014-04-13.{{cite book}}: CS1 maint: location missing publisher (link)
  15. ^ Greenfield, T. (2021). "Corrections to the nomenclature of sawskates (Rajiformes, Sclerorhynchoidei)". Bionomina. 22 (1): 39–41. doi:10.11646/bionomina.22.1.3. S2CID 239067365.
  16. ^ Sternes, P.C.; Shimada, K. (2019). "Paleobiology of the Late Cretaceous sclerorhynchid sawfish, Ischyrhiza mira (Elasmobranchii: Rajiformes), from North America based on new anatomical data". Historical Biology. 31 (10): 1323–1340. doi:10.1080/08912963.2018.1452205. S2CID 90291295.
  17. ^ Case, G.R. (1987). "Borodinopristis schwimmeri, a new ganopristine sawfish from the upper Blufftown Formation (Campanian) of the Upper Cretaceous of Georgia". Bulletin of the New Jersey Academy of Sciences. 32 (1): 25–33.
  18. ^ Keyes, I.W. (1977). "Records of the northern hemisphere Cretaceous sawfish genus Onchopristis (order Batoidea) from New Zealand". New Zealand Journal of Geology and Geophysics. 20 (2): 263–272. Bibcode:1977NZJGG..20..263K. doi:10.1080/00288306.1977.10420706.
  19. ^ Rowe, T.; Cifelli, R.L.; Lehman, T.M.; Weil, A. (1992). "The Campanian Terlingua local fauna, with a summary of other vertebrates from the Aguja Formation, Trans-Pecos Texas". Journal of Vertebrate Paleontology. 12 (4): 472–493. Bibcode:1992JVPal..12..472R. doi:10.1080/02724634.1992.10011475.
  20. ^ Kirkland, J.I.; Eaton, J.G.; Brinkman, D.B. (2013). "Elasmobranchs from Upper Cretaceous freshwater facies in southern Utah". In Titus, A.L.; Loewen, M.A. (eds.). At the Top of the Grand Staircase, the Late Cretaceous of Southern Utah. Bloomington: Indiana University Press. pp. 153–194. ISBN 978-0253008831.
  21. ^ Schubert, J.A.; Wick, S.L.; Lehman, T.M. (2017). "An Upper Cretaceous (middle Campanian) marine chondrichthyan and osteichthyan fauna from the Rattlesnake Mountain sandstone member of the Aguja Formation in West Texas". Cretaceous Research. 69: 6–33. Bibcode:2017CrRes..69....6S. doi:10.1016/j.cretres.2016.08.008. S2CID 133098369.