The Bostobe Formation () is a geological

formation Formation may refer to: Linguistics * Back-formation, the process of creating a new lexeme by removing or affixes * Word formation, the creation of a new word by adding affixes Mathematics and science * Cave formation or speleothem, a secondary ...

in Qaraghandy &

Qyzylorda Kyzylorda ( , formerly known as Kzyl-Orda (), Ak-Mechet (Ак-Мечеть), Perovsk (Перовск), and Fort-Perovsky (Форт-Перовский), is a city in south-central Kazakhstan, capital of Kyzylorda Region and former capital of the ...

, Kazakhastan whose strata date back to the

Late Cretaceous The Late Cretaceous (100.5–66 Ma) is the more recent of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''cre ...

(

Santonian The Santonian is an age in the geologic timescale or a chronostratigraphic stage. It is a subdivision of the Late Cretaceous Epoch or Upper Cretaceous Series. It spans the time between 86.3 ± 0.7 mya ( million years ago) and 83.6 ± 0.7 m ...

to early Campanian stages, approximately 85 Ma). The

sandstone Sandstone is a Clastic rock#Sedimentary clastic rocks, clastic sedimentary rock composed mainly of grain size, sand-sized (0.0625 to 2 mm) silicate mineral, silicate grains, Cementation (geology), cemented together by another mineral. Sand ...

s and

claystone Mudrocks are a class of fine-grained siliciclastic sedimentary rocks. The varying types of mudrocks include siltstone, claystone, mudstone and shale. Most of the particles of which the stone is composed are less than and are too small to ...

s of the formation were deposited in

estuarine An estuary is a partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. Estuaries form a transition zone between river environments and maritime environm ...

fluvial A river is a natural stream of fresh water that flows on land or inside caves towards another body of water at a lower elevation, such as an ocean, lake, or another river. A river may run dry before reaching the end of its course if it ru ...

lacustrine A lake is often a naturally occurring, relatively large and fixed body of water on or near the Earth's surface. It is localized in a basin or interconnected basins surrounded by dry land. Lakes lie completely on land and are separate from t ...

and fluvial-

deltaic A river delta is a landform, archetypically triangular, created by the deposition of the sediments that are carried by the waters of a river, where the river merges with a body of slow-moving water or with a body of stagnant water. The creati ...

environments Environment most often refers to: __NOTOC__ * Natural environment, referring respectively to all living and non-living things occurring naturally and the physical and biological factors along with their chemical interactions that affect an organism ...

. Dinosaur remains are among the fossils that have been recovered from the formation.Weishampel et al. , 2004, pp.593-600 The formation is about thick and consists primarily of clay with interbeds of sand, representing an estuarine environment.Kordikova et al., 2001

Fossil content

'' Khunnuchelys lophorhothon'', a

trionychid Trionychidae is a family of turtles, commonly known as softshell turtles or simply softshells. The family was described by Leopold Fitzinger in 1826. Softshells include some of the world's largest freshwater turtles, though many can adapt to liv ...

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

recovered from the formation, was initially thought to belong to a hadrosaurid dinosaur and classified as cf. ''

Lophorhothon ''Lophorhothon'' is a genus of hadrosauroid dinosaur from the Late Cretaceous of Alabama, Georgia (US state), Georgia, and North Carolina. It was the first genus of dinosaur discovered in Alabama, in the United States. Discovery and naming R ...

sp''.Danilov et al., 2014 ;Mammals * '' Beleutinus orlovi'' * '' Zhalmouzia bazhanovi''Averianov et al., 2014b * '' Parazhelestes sp.''Averianov et al., 2014a ;Ankylosaurs *

Ankylosauridae Ankylosauridae () is a family of armored dinosaurs within Ankylosauria, and is the sister group to Nodosauridae. The oldest known ankylosaurids date to around 122 million years ago and went extinct 66 million years ago during the Cretaceous–Pal ...

indet. ;Ornithopods * ''

Aralosaurus tuberiferus ''Aralosaurus'' was a genus of hadrosaurid dinosaur that lived during the Late Cretaceous in what is now Kazakhstan. It is known only by a posterior half of a skull (devoid of its mandible) and some post-cranial bones found in the Bostobe Format ...

'' * '' Arstanosaurus akkurganensis'' * '' Batyrosaurus rozhdestvenskyi'' ;Sauropods *

Opisthocoelicaudiinae Opisthocoelicaudiinae is a subfamily of titanosaurian dinosaurs from the Late Cretaceous. It was named by John McIntosh in 1990. Opisthocoelicaudiines are known from Mongolia, Argentina, and the United States. Two genera were assigned to Opisthoc ...

Indet. *

Titanosauridae Lithostrotia is a clade of derived titanosaur sauropods that lived during the Early Cretaceous and Late Cretaceous. The group was defined by Upchurch ''et al.'' in 2004 as the most recent common ancestor of ''Malawisaurus'' and ''Saltasaurus'' an ...

indet. *

Sauropoda Sauropoda (), whose members are known as sauropods (; from ''wikt:sauro-, sauro-'' + ''wikt:-pod, -pod'', 'lizard-footed'), is a clade of saurischian ('lizard-hipped') dinosaurs. Sauropods had very long necks, long tails, small heads (relative t ...

indet. ;Theropods *

Caenagnathidae Caenagnathidae is a family of derived caenagnathoid dinosaurs from the Cretaceous of North America and Asia. They are a member of the Oviraptorosauria, and relatives of the Oviraptoridae. Like other oviraptorosaurs, caenagnathids had specialize ...

indet. * Troodontidae indet.Averianov, 2016 * Therizinosauria indet. *

Ornithomimidae Ornithomimidae (meaning "bird-mimics") is an extinct family of theropod dinosaurs which bore a superficial resemblance to modern ostriches. Ornithomimids were fast, omnivorous or herbivorous dinosaurs known mainly from the Late Cretaceous Period ...

indet. * Tyrannosauroidea indet. ;Pterosaurs * '' Aralazhdarcho bostobensis''Averianov, 2004 * '' Samrukia nessovi'' ;Turtles * ''

Adocus foveatus ''Adocus'' is an extinct genus of aquatic turtles belonging to the family Adocidae. Description Species of the genus ''Adocus'' had flattened and smoothly contoured shells with horny sculptured plates. The shells could reach a length of at l ...

'' * '' Anatolemys maximus'' * '' Khunnuchelys lophorhothon'' * '' Lindholmemys gravis'' * '' Shachemys baibolatica'' * ''

Trionyx kansaiensis ''Trionyx'' is a genus of softshell turtles belonging to the family Trionychidae. In the past many species in the family were classified in this genus, but today '' T. triunguis'', the African or Nile softshell turtle, is the only extant Extan ...

'', '' T. onomatoplokos'', '' T. riabinini'' ;Other reptiles * ''

Bishara Bishara, Beshero, Bechara or Beshara (بشارة) is a common Arabic and Coptic name in the Middle East. It is most common in Lebanon, Egypt, Iraq and Syria. In Arabic, Bishāra means “Good News” an Arabic word which is the equivalent to Greek ...

backa'' ;Amphibians * Anura indet. * ''

Eoscapherpeton ''Eoscapherpeton'' is an extinct genus of giant salamander, known from the Late Cretaceous of Central Asia. Fossils have been found in the Cenomanian aged Khodzhakul Formation and Dzharakuduk Formation, Turonian aged Bissekty Formation and the ...

'' ;Fish * '' Gobiates sp.'' ;Flora * Ulmaceae indet.

References

Bibliography

* * * * * * * {{citation , last1=Kordikova , first1=E.G. , last2=Polly , first2=P.D. , last3=Alifanov , first3=V.A. , last4=Roček , first4=Z. , last5=Gunnell , first5=G.F. , last6=Averianov , first6=A.O. , year=2001 , title=Small vertebrates from the late Cretaceous and early Tertiary of the northeastern Aral Sea region, Kazakhstan , journal=

Journal of Paleontology The ''Journal of Paleontology'' is a peer-reviewed scientific journal covering the field of paleontology. It is managed and published by Cambridge University Press on behalf of the Paleontological Society. Indexing The ''Journal of Paleontology ...

, volume=75 , issue=2 , pages=390–400 , doi=10.1017/S0022336000018187 , issn=0022-3360, url=http://doc.rero.ch/record/14896/files/PAL_E2038.pdf

Fossil content

See also

References

Bibliography

Further reading