Hesperotestudo Explained

Hesperotestudo ("Western turtle") is an extinct genus of tortoise native to North and Central America (ranging as far south as Costa Rica^[1]) from the Early Miocene to the Late Pleistocene. Species of Hesperotestudo varied widely in size, with a large undescribed specimen from the Late Pleistocene of El Salvador reaching in carapace length, larger than that of extant giant tortoises.^[2] Historically considered a subgenus of Geochelone, it is now considered to be distantly related to that genus. Its relationships with other tortoises are uncertain. The exposed areas of the bodies of Hesperotestudo species were extensively covered with large dermal ossicles, which in life were covered in keratin. It has been suggested that species of Hesperotestudo were relatively tolerant of cold weather.^[3] Hesperotestudo became extinct at the end of the Pleistocene roughly co-incident with the arrival of the first humans in North America. There is apparently a site in Florida where one individual may have been killed that some suggested were evidence of butchering, although others suggested that the turtle was neither cooked nor does a ledge that was found near it date at the same time as it.^{[4] [5]}

Taxonomy

Species list is based on Vlachos, 2018^[6]

• † Hesperotestudo Williams 1950^[7]
  • †Hesperotestudo bermudae Meylan and Sterrer 2000^[8] Bermuda, Middle Pleistocene c. 310,000 years before present (YBP) - shell length c. 50cm (20inches)^[9]
  • †Hesperotestudo crassiscutata (Leidy 1889)^[10] Florida, Texas, Illinois, South Carolina, (possibly also El Salvador) Middle-Late Pleistocene shell length c. NaNcm (-2,147,483,648inches)
  • †Hesperotestudo ducateli (Collins and Lynn, 1936) Calvert Formation, Maryland, Middle Miocene (Langhian–Serravallian)
  • †Hesperotestudo gilbertii (Hay, 1899) Ogallala Formation, Kansas, Hemphillian, Late Miocene-Early Pliocene (Tortonian–Zanclean)
  • †Hesperotestudo orthopygia (Cope, 1878) (syn= Xerobates cyclopygius Cope, 1878 =Caryoderma snovianum Cope, 1886 = Testudo rexroadensis Oelrich, 1952 = Geochelone nordensis Holman, 1973) Kansas, California, Nebraska, Late Miocene-Pliocene shell length c. 120cm (50inches)^[11]
  • †Hesperotestudo osborniana (Hay, 1905)(syn= Testudo arenivaga Hay, 1906 = Testudo farri Hay, 1908 = Testudo impensa Hay, 1908 = Testudo orthopygia angusticeps Matthew, 1924) Colorado, Nebraska, Montana, Early Miocene-Early Pliocene shell length up to 92cm (36inches)
  • †Hesperotestudo turgida (Cope, 1892) (syn = Testudo incisa Hay, 1916a = Testudo riggsi Hibbard, 1944 = Testudo wilsoni Milstead, 1956 = Geochelone johnstoni Auffenberg 1962 = Geochelone alleni Auffenberg, 1966 = Geochelone oelrichi Holman, 1972a = Geochelone mlynarskii Auffenberg, 1988) Florida, Oklahoma, Kansas, Texas, Nebraska, Late Miocene-Late Pleistocene shell length c. NaNcm (-2,147,483,648inches)
  • †Hesperotestudo williamsi (Auffenberg, 1964) Oakville Formation, Texas, Early Miocene (Burdigalian) shell length c. 33.4cm (13.1inches)

Notes and References

1. Carbot-Chanona . Gerardo . Rivera-Velázquez . Gustavo . Jiménez-Hidalgo . Eduardo . Reynoso . Víctor Hugo . 2020-11-04 . The fossil record of turtles and tortoises (Testudines) of Mexico, Central America and the Caribbean Islands, with comments on its taxonomy and paleobiogeography: a bibliographic review . Revista Mexicana de Ciencias Geológicas . 37 . 3 . 269–283 . 10.22201/cgeo.20072902e.2020.3.1581 . 2007-2902. free .
2. Rhodin, A.G.J. . Thomson, S. . Georgalis, G. . Karl, H.-V. . Danilov, I.G. . Takahashi, A. . de la Fuente, M.S. . Bourque, J.R. . Delfino M. . Bour, R. . Iverson, J.B. . Shaffer, H.B. . van Dijk, P.P. . 2015 . Turtles and tortoises of the world during the rise and global spread of humanity: first checklist and review of extinct Pleistocene and Holocene chelonians. . live . Chelonian Research Monographs . 5 . 8 . 000e.1–66 . 10.3854/crm.5.000e.fossil.checklist.v1.2015 . https://web.archive.org/web/20220921185503/https://iucn-tftsg.org/wp-content/uploads/file/Accounts/crm_5_000e_fossil_checklist_v1_2015.pdf . 21 September 2022 . free . Turtle Extinctions Working Group.
3. Moll. Don. Brown. Lauren E.. 2017. Reinterpretation of the Climatic Adaptation of Giant Fossil Tortoises in North America. Herpetological Journal. en-gb. 27. 3. 276–286.
4. Book: Anderson. David G.. Sassaman. Kenneth E.. Dunbar. James S.. Webb. S. David. 1996. The Paleoindian and Early Archaic Southeast. 17. Bone and Ivory Tools from Submerged Paleoindian Sites in Florida. University Alabama Press. 331–353.
5. Grayson. Donald K.. Meltzer. David J.. 2003. A requiem for North American overkill. Journal of Archaeological Science. 30. 5. 585–593. 10.1016/S0305-4403(02)00205-4. 2003JArSc..30..585G .
6. Vlachos. Evangelos. 2018-04-17. A Review of the Fossil Record of North American Turtles of the Clade Pan-Testudinoidea. Bulletin of the Peabody Museum of Natural History. 59. 1. 3. 10.3374/014.059.0101. 214641639 . 0079-032X. 11336/117896. free.
7. Williams, E.E. 1950. Testudo cubensis and the evolution of Western Hemisphere tortoises. Bulletin of the American Museum of Natural History 95:1–36.
8. Meylan . P. A. . Sterrer . W. . January 2000 . Herperotestudo (Testudines: Testudinidae) from the Pleistocene of Bermuda, with comments on the phylogenetic position of the genus . . 128 . 1 . 51–76 . 10.1111/j.1096-3642.2000.tb00649.x . free.
9. Olson . S. L. . Meylan . P. A. . December 2009 . A Second Specimen of the Pleistocene Bermuda Tortoise, Hesperotestudo bermudae Meylan and Sterrer . . 8 . 2 . 211–212 . 10.2744/CCB-0766.1 . 2012-04-12 . 85595118.
10. Leidy, J. 1889. Description of vertebrate remains from Peace Creek, Florida. Transactions of the Wagner Free Institute of Science of Philadelphia 2:19–31.
11. Biewer . Jacob . Sankey . Julia . Hutchison . Howard . Garber . Dennis . 2016-03-08 . A fossil giant tortoise from the Mehrten Formation of Northern California . PaleoBios . 33 . 10.5070/p9331030312 . 2373-8189 . free.