''Polysternon'' is a genus of

turtle Turtles are an order of reptiles known as Testudines, characterized by a special shell developed mainly from their ribs. Modern turtles are divided into two major groups, the Pleurodira (side necked turtles) and Cryptodira (hidden necked ...

s in the extinct family

Bothremydidae Bothremydidae is an extinct family of side-necked turtles (Pleurodira) known from the Cretaceous and Cenozoic. They are closely related to Podocnemididae, and are amongst the most widely distributed pleurodire groups, with their fossils having b ...

. It was described by Portis in 1882, and contains the species ''P. provinciale'' (originally placed in the genus ''

Pleurosternon ''Pleurosternon'' is an extinct genus of freshwater pleurosternid turtle from the latest Jurassic to earliest Cretaceous of Europe. Its type species, ''P. bullocki'' was described by the paleontologist Richard Owen (noted for coining the word ...

''), which existed during the

Cretaceous The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of ...

of what is now

France France (), officially the French Republic ( ), is a country primarily located in Western Europe. It also comprises of overseas regions and territories in the Americas and the Atlantic, Pacific and Indian Oceans. Its metropolitan ar ...

; ''P. atlanticum'', which existed during the

Laño Laño ( eu, Lañu) is a hamlet and '' concejo'' (a small administrative subdivision) in Condado de Treviño within the Treviño enclave; which is administratively part of the Spanish province of Burgos, but which is completely surrounded by the ...

in what is now

Spain , image_flag = Bandera de España.svg , image_coat = Escudo de España (mazonado).svg , national_motto = '' Plus ultra'' ( Latin)(English: "Further Beyond") , national_anthem = (English: "Royal March") , ...

, and a new species, ''P. isonae'', from the Late

Maastrichtian The Maastrichtian () is, in the ICS geologic timescale, the latest age (uppermost stage) of the Late Cretaceous Epoch or Upper Cretaceous Series, the Cretaceous Period or System, and of the Mesozoic Era or Erathem. It spanned the interv ...

of Spain. The

species epithet Specific name may refer to: * in Database management systems, a system-assigned name that is unique within a particular database In taxonomy, either of these two meanings, each with its own set of rules: * Specific name (botany) A botanical name ...

of ''P. isonae'' refers to the municipality

Isona i Conca Dellà Isona i Conca Dellà is a municipality in the ''comarca'' of the Pallars Jussà in Catalonia, Spain. It is situated in the valley of the Conques river in the south-east of the ''comarca''. It was formed in 1970 by the fusion of the following muni ...

Catalonia Catalonia (; ca, Catalunya ; Aranese Occitan: ''Catalonha'' ; es, Cataluña ) is an autonomous community of Spain, designated as a '' nationality'' by its Statute of Autonomy. Most of the territory (except the Val d'Aran) lies on the no ...

, where the type specimen was discovered in the

Tremp Formation The Tremp Formation ( es, Formación de Tremp, ca, Formació de Tremp), alternatively described as Tremp Group ( es, Grupo Tremp), is a geological formation in the comarca Pallars Jussà, Lleida, Spain. The formation is restricted to the Tr ...

Species

* ''Polysternon provinciale'' Matheron, 1869 * ''Polysternon atlanticum'' Lapparent de Broin & Murelaga, 1996 * ''Polysternon isonae'' Marmi et al., 2012

Distribution

Fossils of ''Polysternon'' have been found in:''Polysternon''
at

Fossilworks Fossilworks is a portal which provides query, download, and analysis tools to facilitate access to the Paleobiology Database, a large relational database assembled by hundreds of paleontologists from around the world. History Fossilworks was cre ...

.org * Rognacian Formation -

* Vitoria, Sierra Perenchiza and

s -

References

External links

''Polysternon''
at the

Paleobiology Database The Paleobiology Database is an online resource for information on the distribution and classification of fossil animals, plants, and microorganisms. History The Paleobiology Database (PBDB) originated in the NCEAS-funded Phanerozoic Marine Paleo ...

{{Testudines Prehistoric turtle genera Late Cretaceous turtles Maastrichtian life Late Cretaceous reptiles of Europe Cretaceous France Fossils of France Cretaceous Spain Fossils of Spain Tremp Formation Fossil taxa described in 1882 Extinct turtles