Interesting; the range of overlap must be wider than the original description of the species in the aforementioned papers stated looking at a map, the Kama does look like it would provide a formidable barrier.
DISTRIBUTION OF TWO BADGER SPECIES (MUSTELIDAE, MELES) IN EUROPEAN PART OF RUSSIA
A.V. Abramov, A.P. Saveljev, V.N. Sotnikov, V.A. Solovyev, 2003
The boundary between distribution ranges of European M. meles and Asian badgers M. leucurus is Volga River (up to Middle Volga). M. meles distributed westwards of Volga River, M. leucurus distributed from Volga River to the east. The only locality of Asian badger’ distribution in the right bank of Volga River is Zhiguli Nature Reserve. It was found that the Asian badger M. leucurus widely distributed in the Urals and area westward of Ural Mts. The European badger M. meles was found in
Nizhnii Novgorod Province (both sides of Volga River). M. meles distributed in the west and north districts of Kirov Province, east and south of Kirov Province are inhabited by M. leucurus. The sympatric zone between these species is country between Volga and Kama rivers.
The taxonomic status of badgers (Mammalia, Mustelidae) from Southwest Asia based on cranial morphometrics,with the redescription of Meles canescens
ALEXEI V. ABRAMOV & ANDREY YU. PUZACHENKO, 2013
The European badger is distributed throughout Europe, from the British Islands eastwards to the west bank of the River Volga. The Asian badger occurs from Eastern Europe (the east bank of Volga River) throughout the Urals, Kazakhstan and Middle Asia, southern Siberia and Mongolia to China and Korea. In the European part of Russia, the distribution border between M. meles and M. leucurus goes throughout Lower and Middle Volga and Volga—Kama Interfluves (Abramov et al. 2003; Abramov & Puzachenko 2006).
I've just asked my university teacher about last surveys. He said that last and wide surveys stated that both species are common in our region, and hybrids are not very rare (only data on coloration and craniometry). He will send me materials next week, maybe I will find something interesting for you.
