The Ukureyskaya Formation, also referred to as the Ukurey Formation, is a geological formation in Zabaykalsky Krai, part of the Russian Far East. It is made up of Middle Jurassic and Late Jurassic layers. It covers large areas around Kulinda."The Kulinda fossil site", University of Bristol Palaeobiology Research Group. Retrieved 4 April 2015
History The Ukureyskaya Formation was mentioned by Sinitsa & Starukhina (1986),Sinitsa S.M., Starukhina S. (1986) New data and problems in stratigraphy and palaeontology of the Upper Mesozoic in East Transbaikalia. In: Novye Dannye po Geologii Zabaikal’ya. Min. Geol. RSFSR, Moscow, pp 46–51 and was first discovered by Sofia M. Sinitsa and her team from the Russian Academy of Sciences before being excavated in 2010 by a group of Russian and Belgian palaeontologists;Sinitsa S.M. (2011). Jurassic dinosaurs of Transbaikalia. In: Sinitsa SM (ed) Environmental cooperative studies in the cross-border ecological region: Russia, China, and Mongolia. Inst. Min. Res., Ecol. Cryol. SB RAS, Chita, pp 173–176 during this time, the holotype of Kulindadromeus zabaikalicus was discovered. Excavations wrapped up in 2013 or 2014.Dan Vergano, 2014, "Siberian Discovery Suggests Almost All Dinosaurs Were Feathered", National Geographic Daily News
Description The volcanic ash layers of the Ukureyskaya Formation form a Konservat-Lagerstätte with an exceptional preservation, and it likely represents a nearshore lacustrine or estuarine-deltaic environment similar to the Yixian Formation.
In total, two bone beds were identified during the excavations that took place between 2010 and 2013/14; Bonebed 4 is older than Bonebed 3.
Age Sinitsa & Starukhina (1986) and Sinitsa (2011) suggested that the Ukureyskaya Formation dated to the Late Jurassic-Early Cretaceous.
Godefroit et al. (2014) and Alivanov & Saveliev (2014) have suggested that as a whole, the Ukureyskaya Formation dates to the Bajocian-Tithonian, (in Russian; English translation published in ) while more recent dating work by Cincotta et al. (2019) suggests that the layers containing the remains of Kulindadromeus are Bathonian in age.
Paleofauna
+Paleofauna of the Ukureyska FormationGenusSpeciesLocationStratigraphic positionMaterialNotesImageCrustaceaIndeterminateKulinda"Indeterminate remains"InsectaIndeterminateKulindaRepresented by multiple species. KulindadromeusK. zabaikalicusKulinda"Base of the Ukureyska Formation""Hundreds of disarticulated skeletons including six skulls"Synonyms include Daurosaurus olovus and Lepidocheirosaurus natalis.Andrea Cau (November 24, 2015). "Cosa è Lepidocheirosaurus?". Theropoda. Retrieved November 25, 2015.OrnithopodaIndeterminateKulinda"Indeterminate remains"Represents an unnamed genus that is distinct from Kulindadromeus.TheropodaIndeterminateKulinda"Single tooth"Based on undiagnostic remains.
References