The Alai Beds is an Early Eocene (Ypresian, or Bumbanian in the ALMA classification) geologic formation in the Osh Region of southwestern Kyrgyzstan. The formation has provided many fossils of mammals, lizards, turtles and snakes.Alai Beds at Fossilworks.org
Description The Paleogene Alai Beds have a limited distribution, and are restricted to the northern slope of Aktash Range, formed by Paleozoic rocks, which is one of the foothills of the Turkestan Range. The Paleogene deposits on the Aktash Range are badly exposed, they can be observed only in three outcrops, 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-bearing limestones 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 udovichenkoiAverianov, 1994b Nuryctes alayensisLopatin & Averianov, 2004 Palaeoryctidae indet.Lopatin, 2006
Hyaenodonta Isphanatherium ferganensisLavrov & Averianov, 1998 Neoparapterodon sp.
Lipotyphla Protogalericius averianovi
Perissodactyls
Eoletes tianshanicus Pataecops minutissimusAverianov, 1994b Lushiamynodon kirghisensis Teleolophus medius
Rodents
Aktashmys montealbusAverianov, 1994a, p.406Averianov & Lopatin, 2005 Alaymys ctenodactylusAverianov, 1994a, p.401 Anatolimys rozhdestvenskiiAverianov, 1994a, p.402 Gobiolagus hekkeriLopatin & 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 turkestanicusDanilov & Averianov, 1999 Palaeophis ferganicus Boidae indet.
Turtles Hadrianus vialoviAverianov & Godinot, 2005Danilov & Averianov, 1999 Cheloniinae indet.Averianov, 2002
See also
Ypresian formations Ieper Group of Belgium Fur Formation of Denmark London Clay Formation of England Silveirinha Formation of Portugal Wasatchian formations Nanjemoy Formation of the eastern United States Wasatch Formation of the western United States Itaboraian formations Itaboraí Formation of Brazil Laguna del Hunco Formation of Argentina
References
Bibliography