Titanochelon
Temporal range: Early Miocene–Early Pleistocene
Titanochelon perpiniana
Shell of Titanochelon vitodurana
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Order: Testudines
Suborder: Cryptodira
Superfamily: Testudinoidea
Family: Testudinidae
Genus: †Titanochelon
Pérez-García and Vlachos, 2014.
Type species
Titanochelon bolivari
(Hernandez-Pacheco, 1917)
Species

See text

Titanochelon is an extinct genus of giant tortoises known from the Early Miocene to the beginning of the Pleistocene in Europe, extending from the Iberian Peninsula to Anatolia. Some members of the genus were larger than extant giant tortoises, with a shell length of up to 2 m (6 ft 7 in).[1][2]

Taxonomy

There are approximately 10 known species in the genus, most of which were originally assigned to Testudo (a genus which formally encompassed almost all fossil tortoises) or Cheirogaster, the type species of which, Cheirogaster maurini is known from the Eocene of France and is quite different to the species assigned to Titanochelon. After a major systematic revision in 2014, the genus Titanochelon was created to house these related species.[1][3][4]

The giant tortoise species "Testudo" gymnesica Bate, 1914 from the Lower Pliocene-Lower Pleistocene of the Balearic Islands was formerly suggested to be possibly attributable to this genus, but the taxon displays notable differences from the species assigned to Titanochelon.[6] Remains from the Pleistocene of Malta were also considered possibly attributable to this genus.[7] In 2022, "Testudo" gymnesica and the Maltese species were assigned to the new genus Solitudo.[8]

Evolutionary history

Phylogenetic analyses have recovered Titanochelon as most closely related to Stigmochelys (the leopard tortoise), which is native to Africa, suggesting the genus has an African origin.[7][9] Fossils have been recovered from across Europe beginning in the Early Miocene from Portugal,[4] Spain, France, Switzerland, Germany, Austria, the Czech Republic,[10] Greece, Bulgaria, and Anatolia.[3] The youngest known defintiive remains of the genus are known from the Early Pleistocene Fonelas P-1 site of Granada in southern Spain, dating to around 2.0 million years ago. Their extinction was likely related to climatic cooling due to the onset of glaciation at the beginning of the Pleistocene.[2]

References

  1. ^ a b Pérez-García, Adán; Vlachos, Evangelos (2014-11-01). "New generic proposal for the European Neogene large testudinids (Cryptodira) and the first phylogenetic hypothesis for the medium and large representatives of the European Cenozoic record". Zoological Journal of the Linnean Society. 172 (3): 653–719. doi:10.1111/zoj12183. ISSN 0024-4082.
  2. ^ a b Pérez-García, Adán; Vlachos, Evangelos; Arribas, Alfonso (March 2017). "The last giant continental tortoise of Europe: A survivor in the Spanish Pleistocene site of Fonelas P-1" (PDF). Palaeogeography, Palaeoclimatology, Palaeoecology. 470: 30–39. Bibcode:2017PPP...470...30P. doi:10.1016/j.palaeo.2017.01.011. hdl:10261/277114. Archived from the original (PDF) on 26 January 2022.
  3. ^ a b Hans Volker Karl, Ulrich Staesche, Amtyaz Safi New findings of neogene tortoises Titanochelon kayadibiensis sp. nov. and Protestudo bessarabica (Riabinin, 1918) (Testudinidae) from the Miocene of western Turkey, with a review of fossil turtles of Turkey SPC Journal of Environmental Sciences, 3 (1) (2021) 1-9
  4. ^ a b Pérez-García, A.; Vlachos, E.; Mocho, P. (2017-08-18). "The westernmost records of extinct large European tortoises: the presence of Titanochelon (Testudinidae) in the Miocene of Portugal". Historical Biology. 29 (6): 854–861. doi:10.1080/08912963.2016.1261134. ISSN 0891-2963. S2CID 88612295.
  5. ^ Pappa, Irena; Vlachos, Evangelos; Moser, Markus (2023-06-26). "A new species of a giant tortoise from Sandelzhausen ( MN5 , Burdigalian/Langhian boundary, Early/Middle Miocene , South Germany )". The Anatomical Record. doi:10.1002/ar.25280. ISSN 1932-8486. PMID 37358053. S2CID 259249972.
  6. ^ Luján, Ángel H.; Alcover, Josep Antoni; Ivanov, Martin; Torres, Enric; Alba, David M. (2020-04-09). "Revisión taxonómica de "Testudo" gymnesica Bate, 1914 (Testudines, Testudinidae) a partir de la descripción del material tipo de Menorca (Islas Baleares)" [Taxonomic revision of “Testudo” gymnesica Bate, 1914 (Testudines, Testudinidae) from the description of the type material from Menorca (Balearic Islands)]. Spanish Journal of Palaeontology (in Spanish). 32 (2): 261–278. doi:10.7203/sjp.32.2.17043. ISSN 2660-9568. S2CID 135308837.
  7. ^ a b Pérez‐García, Adán; Vlachos, Evangelos; Murelaga, Xabier (May 2020). Mannion, Philip (ed.). "A large testudinid with African affinities in the post‐Messinian (lower Pliocene) record of south‐eastern Spain". Palaeontology. 63 (3): 497–512. doi:10.1111/pala.12468. ISSN 0031-0239. S2CID 214232312.
  8. ^ Valenti, Pietro; Vlachos, Evangelos; Kehlmaier, Christian; Fritz, Uwe; Georgalis, Georgios L; Luján, Àngel Hernández; Miccichè, Roberto; Sineo, Luca; Delfino, Massimo (2022-07-02). "The last of the large-sized tortoises of the Mediterranean islands". Zoological Journal of the Linnean Society. 196 (4): 1704–1717. doi:10.1093/zoolinnean/zlac044. ISSN 0024-4082.
  9. ^ Vlachos, Evangelos; Rabi, Márton (December 2018). "Total evidence analysis and body size evolution of extant and extinct tortoises (Testudines: Cryptodira: Pan-Testudinidae)". Cladistics. 34 (6): 652–683. doi:10.1111/cla.12227. PMID 34706483. S2CID 90619565.
  10. ^ Březina J., Luján A.H., Calábková G. and Ivanov M. (2019): Revize historického nálezu obří želvy z Brněnskych Písků (Stredni Miocén, Spodní Baden). Acta. Mus. Moraviae, Sci. geol. CIII 1:113-128; Brno; [Revision on historical finding of the giant Turtle from the Brno Sand (Middle Miocene, Lower Badenium)] .
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