''Titanochelon'' is an extinct genus of giant

tortoises Tortoises () are reptiles of the family Testudinidae of the order Testudines (Latin: ''tortoise''). Like other turtles, tortoises have a shell to protect from predation and other threats. The shell in tortoises is generally hard, and like other ...

known from the Early

Miocene The Miocene ( ) is the first geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and means "less recen ...

to the beginning of the

Pleistocene The Pleistocene ( , often referred to as the ''Ice age'') is the geological Epoch (geology), epoch that lasted from about 2,580,000 to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fina ...

in Europe, extending from the

Iberian Peninsula The Iberian Peninsula (), ** * Aragonese and Occitan: ''Peninsula Iberica'' ** ** * french: Péninsule Ibérique * mwl, Península Eibérica * eu, Iberiar penintsula also known as Iberia, is a peninsula in southwestern Europe, defi ...

Anatolia Anatolia, tr, Anadolu Yarımadası), and the Anatolian plateau, also known as Asia Minor, is a large peninsula in Western Asia and the westernmost protrusion of the Asian continent. It constitutes the major part of modern-day Turkey. The re ...

. Some members of the genus were larger than extant

giant tortoise Giant tortoises are any of several species of various large land tortoises, which include a number of extinct species, as well as two extant species with multiple subspecies formerly common on the islands of the western Indian Ocean and on the ...

s, with a shell length of up to .

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 The Eocene ( ) Epoch is a geological epoch (geology), epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name ''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.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 * '' Titanochelon bolivari'' (Hernandez-Pacheco, 1917) (type)

, Miocene * '' Titanochelon bacharidisi'' (Vlachos et al., 2014) Greece, Bulgaria, Late Miocene * '' Titanochelon perpiniana'' (Deperet 1885) France, Pliocene *''

Titanochelon schafferi ''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 tortoise ...

'' (Szalai, 1931) Samos, Greece, Miocene *'' Titanochelon vitodurana'' (Biedermann 1862) Switzerland, Early Miocene *'' Titanochelon kayadibiensis'' Karl, Staesche & Safi, 2021, Anatolia, Miocene *'' Titanochelon eurysternum'' (Gervais, 1848–1852) France, Miocene *'' Titanochelon ginsburgi'' (de Broin, 1977 ) France, Miocene *'' Titanochelon leberonensis'' (Depéret, 1890) France, Miocene The species ''"Testudo" gymnesica'' Bate, 1914 from the Lower Pliocene-Lower Pleistocene of the

Balearic Islands The Balearic Islands ( es, Islas Baleares ; or ca, Illes Balears ) are an archipelago in the Balearic Sea, near the eastern coast of the Iberian Peninsula. The archipelago is an autonomous community and a province of Spain; its capital is ...

was formerly suggested to be possibly attributable to this genus, but the taxon displays notable differences from the species assigned to ''Titanochelon''. Remains from the

of Malta were also considered possibly attributable to this genus. In 2022, "''Testudo''" ''gymnesica'' and the Maltese species were assigned to the new genus '' Solitudo.''

Evolutionary history

Phylogenetic analyses In biology, phylogenetics (; from Greek φυλή/ φῦλον [] "tribe, clan, race", and wikt:γενετικός, γενετικός [] "origin, source, birth") is the study of the evolutionary history and relationships among or within groups o ...

have recovered ''Titanochelon'' as most closely related to '' Stigmochelys'' (the

leopard tortoise The leopard tortoise (''Stigmochelys pardalis'') is a large and attractively marked tortoise found in the savannas of eastern and southern Africa, from Sudan to the southern Cape. It is the only extant member of the genus ''Stigmochelys'', althou ...

), which is native to Africa, suggesting the genus has an African origin. Fossils have been recovered from across Europe beginning in the Early Miocene from Portugal, Spain, France, Switzerland, Germany, Austria, the Czech Republic,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; evision on historical finding of the giant Turtle from the Brno Sand (Middle Miocene, Lower Badenium). Greece, Bulgaria, and Anatolia. 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.

References

{{Taxonbar, from1=Q28871162, from2=Q50368425, from3=Q51153051, from4=Q51310094, from5=Q51310095, from6=Q50368426 Testudinidae Taxa described in 2014 Prehistoric turtle genera