Chamrin-Us (PIN coll. 3779) [SMPE] (Cretaceous to of Mongolia)

Also known as Soviet-Mongolian Paleontological Expedition, Khamareen Us, Gashunu-Chuduk, Khamryn-Us, Gashun-Khuduk, Gashuuny Khudag

Where: Dornogov, Mongolia (43.9° N, 111.4° E: paleocoordinates 46.9° N, 107.9° E)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Dzunbain Formation, Aptian to Aptian (125.0 - 100.5 Ma)

• 60 m thick strata - called Chuchtuksk = Khukhtyk = Dzunbain = Dzunbayn = Zuunbayan Formation

• group of beds-level stratigraphic resolution

Environment/lithology: fluvial-lacustrine; ferruginous, brown, gray, green claystone and gray, yellow sandstone

• large lake deposit (psittacosaurs) = clay, supposedly near-shore; river bed (ankylosaurs, sauropods) = sandstone channels
• bones in small lenses within green, gray, sometimes dark brown (iron-bearing) claystone; also a gray channel sandstone

•"grayish-yellow sandstone"

Size class: macrofossils

Preservation: trace

Collected by SMPE in 1971, 1977, 1981

Collection methods: surface (float), surface (in situ), mechanical,

Primary reference: N. N. Kalandadze and S. M. Kurzanov. 1974. Nizhnemelove mestonakhozhdeniya nazemnykh pozvonochnykh Mongolii [Lower Cretaceous terrestrial vertebrate localities of Mongolia]. In N. N. Kramarenko, B. Luvsandansan, Yu. I. Voronin, R. Barsbold, A. K. Rozhdestve (eds.), Mesozoic and Cenozoic Faunas and Biostratigraphy of Mongolia. The Joint Soviet-Mongolian Paleontological Expedition, Transactions 1:288-295 [M. Carrano/M. Carrano/M. Carrano]more details

Purpose of describing collection: general faunal/floral analysis

PaleoDB collection 32362: authorized by Matthew Carrano, entered by Matthew Carrano on 26.06.2003, edited by Patricia Holroyd

Creative Commons license: CC BY (attribution)

Taxonomic list

Reptilia
 Ornithischia - Stegosauridae
Mongolostegus exspectabilis n. gen. n. sp.4 Tumanova and Alifanov 2018 ornithischian
PIN 3779/15
Wuerhosaurus mongoliensis n. sp.5 Ulansky 2014 ornithischian
PIN 3779/12
 Ornithischia - Ankylosauridae
Shamosaurus scutatus n. gen. n. sp.3
Shamosaurus scutatus n. gen. n. sp.3 Tumanova 1983 ankylosaurid
 Ornithischia - Psittacosauridae
Psittacosauridae indet.2 Osborn 1923 ceratopsian
 Saurischia -
 Theropoda - Troodontidae
Troodontidae indet.1 Gilmore 1924 maniraptoran
SPS 100/44