Revision of the fossil material attributed to Stephanorhinus kirchbergensis (Jäger 1839) (Mammalia, Rhinocerotidae) preserved in the museum collections of the Russian Federation

The present work is devoted to the revision of the fossil remains ascribed to Stephanorhinus kirchbergensis (Jäger 1839), better known in Russia as “nosorog Merka”, found on Russian territory and preserved in the museum collections of the Russian Federation. A great amount of palaeontological material has been studied using morphological and non-metric characters. Unfortunately, a large part of the fossil material cited in the literature and ascribed to this taxon had not been traced. In any case, the rarity of this species, despite its being widely spread throughout the Eurasian continent, is apparent in Russian territory as well as in the European area. S. kirchbergensis is a rhinoceros still little investigated, and consequently, not well known yet. A brief history of S. kirchbergensis is also added.