The skull of Stephanorhinus kirchbergensis (Jäger 1839) (Mammalia, Rhinocerotidae) from the Irkutsk region (Southwest Eastern Siberia)

The skull discovered in the Irkutsk region (Southwest Eastern Siberia), previously attributed to “Rhinoceros Merckii Jäger 1839” (sic) (=Stephanorhinus kirchbergensis [Jäger 1839]) and preserved in the collections of the Zoological Institute of the Russian Academy of Science in St. Petersburg, is described here. It represents one of the five skulls ascribed to this taxon discovered until now in Eurasia and the only one recovered and existing on Russian territory. Some notes on three other skulls (from Daxlanden, Mosbach, and Steinheim an der Murr) ascribed to the same species are also included. Unlike other Plio-Pleistocene rhinoceroses (the “woolly rhino” included) which abound in the Eurasian continent, S. kirchbergensis, better known in Russia, and in the ex Soviet Union, as “nosorog Merka”, seems to be rather rare on this wide territory, being reported from a relatively limited number of localities only. This is the case of one of the two records of this species from Eastern Siberia, and one of the very few from Russia.