The Alai Beds is an

Early Eocene In the geologic timescale the Ypresian is the oldest age (geology), age or lowest stage (stratigraphy), stratigraphic stage of the Eocene. It spans the time between , is preceded by the Thanetian Age (part of the Paleocene) and is followed by th ...

(

Ypresian In the geologic timescale the Ypresian is the oldest age (geology), age or lowest stage (stratigraphy), stratigraphic stage of the Eocene. It spans the time between , is preceded by the Thanetian Age (part of the Paleocene) and is followed by th ...

, or Bumbanian in the ALMA classification)

geologic formation A geological formation, or simply formation, is a body of rock having a consistent set of physical characteristics ( lithology) that distinguishes it from adjacent bodies of rock, and which occupies a particular position in the layers of rock exp ...

in the

Osh Region Osh is a Regions of Kyrgyzstan, region of Kyrgyzstan. Its capital is Osh, which is not part of the region. It is bounded (clockwise) by Jalal-Abad Region, Naryn Region, China (Xinjiang), Tajikistan (Districts under Central Government Jurisdiction ...

of southwestern

Kyrgyzstan Kyrgyzstan, officially the Kyrgyz Republic, is a landlocked country in Central Asia lying in the Tian Shan and Pamir Mountains, Pamir mountain ranges. Bishkek is the Capital city, capital and List of cities in Kyrgyzstan, largest city. Kyrgyz ...

. The formation has provided many

fossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserve ...

s of

mammal A mammal () is a vertebrate animal of the Class (biology), class Mammalia (). Mammals are characterised by the presence of milk-producing mammary glands for feeding their young, a broad neocortex region of the brain, fur or hair, and three ...

lizard Lizard is the common name used for all Squamata, squamate reptiles other than snakes (and to a lesser extent amphisbaenians), encompassing over 7,000 species, ranging across all continents except Antarctica, as well as most Island#Oceanic isla ...

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 ...

s and

snake Snakes are elongated limbless reptiles of the suborder Serpentes (). Cladistically squamates, snakes are ectothermic, amniote vertebrates covered in overlapping scales much like other members of the group. Many species of snakes have s ...

s.Alai Beds
at

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.org

Description

The Paleogene Alai Beds have a limited distribution, and are restricted to the northern slope of Aktash Range, formed by

Paleozoic The Paleozoic ( , , ; or Palaeozoic) Era is the first of three Era (geology), geological eras of the Phanerozoic Eon. Beginning 538.8 million years ago (Ma), it succeeds the Neoproterozoic (the last era of the Proterozoic Eon) and ends 251.9 Ma a ...

rocks, which is one of the foothills of the

Turkestan Range One of the northern extensions of the Pamir-Alay system, the Turkestan Range (; ; ; ) stretches for a total length of 340 km from the Alay Mountains on the border of Kyrgyzstan with Tajikistan to the Samarkand oasis in Uzbekistan. It runs in ...

. The Paleogene deposits on the Aktash Range are badly exposed, they can be observed only in three

outcrop An outcrop or rocky outcrop is a visible exposure of bedrock or ancient superficial deposits on the surface of the Earth and other terrestrial planets. Features Outcrops do not cover the majority of the Earth's land surface because in most p ...

s, separated by short distances about . Despite their close position, the Paleogene deposits in these outcrops are varied greatly in composition and thickness of layers.Averianov, 1994a, p.399 The lower Alai Beds contain of silts and siltstones, and the upper part comprises

oyster Oyster is the common name for a number of different families of salt-water bivalve molluscs that live in marine or brackish habitats. In some species, the valves are highly calcified, and many are somewhat irregular in shape. Many, but no ...

-bearing

limestone Limestone is a type of carbonate rock, carbonate sedimentary rock which is the main source of the material Lime (material), lime. It is composed mostly of the minerals calcite and aragonite, which are different Polymorphism (materials science) ...

s of which are exposed. At the base of the Upper Alai Beds there is a layer of conglomerate which produces a number of marine vertebrates, but a few terrestrial vertebrates including mammals. The section I1 is more complete and has a greater thickness, but produces a few shark teeth only. The third Paleogene section, where the mammal bearing locality Andarak 2 is located, has a much greater thickness of sands of the lower Alai Beds (more than of visible thickness) with some horizons of oyster-bearing conglomerates.Averianov, 1994a, p.400

Fossil content

The formation has provided the following fossils:

Mammals

;Artiodactyls * '' Eolantianius russelli'' * '' Diacodexis sp.'' * Diacodexeidae indet. ;Cimolesta * '' Metasarcodon udovichenkoi''Averianov, 1994b * '' Nuryctes alayensis''Lopatin & Averianov, 2004 * Palaeoryctidae indet.Lopatin, 2006 ;Hyaenodonta * '' Isphanatherium ferganensis''Lavrov & Averianov, 1998 * '' Neoparapterodon sp.'' ;Lipotyphla * '' Protogalericius averianovi'' ;Perissodactyls * '' Eoletes tianshanicus'' * '' Pataecops minutissimus''Averianov, 1994b * '' Sharamynodon kirghisensis'' * '' Teleolophus medius'' ;Rodents * '' Aktashmys montealbus''Averianov, 1994a, p.406Averianov & Lopatin, 2005 * '' Alaymys ctenodactylus''Averianov, 1994a, p.401 * '' Anatolimys rozhdestvenskii''Averianov, 1994a, p.402 * '' Gobiolagus hekkeri''Lopatin & Averianov, 2006 * '' Khodzhentia vinogradovi'' * '' Advenimus cf. burkei'' * '' Petrokozlovia cf. notos'' * '' Saykanomys cf. bohlini'' * '' ?Adolomys sp.'' * Ctenodactyloidea indet.Averianov & Danilov, 1996a

Reptiles

;Lizards * '' ?Saniwa sp.''Averianov & Danilov, 1997 * Agamidae indet.Averianov & Danilov, 1996b * Uromastycinae indet. ;Snakes * '' Calamagras turkestanicus''Danilov & Averianov, 1999 * '' Palaeophis ferganicus'' * Boidae indet. ;Turtles * '' Hadrianus vialovi''Averianov & Godinot, 2005Danilov & Averianov, 1999 * Cheloniinae indet.Averianov, 2002

References

Bibliography

* * * * * * * * * * * * * * * {{cite journal , last=Averianov , first=A. O , year=1994b , title=A new species of ''Sarcodon'' (Mammalia, Palaeoryctoidea) from the Lower Eocene of Kirgizia , journal=

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