Stephanorhinus

Stephanorhinus is an extinct genus of two-horned rhinoceros native to Eurasia and North Africa that lived from Late Miocene or Pliocene until their extinction in the Late Pleistocene. Species of Stephanorhinus were the predominant and often only species of rhinoceros in much of temperate Eurasia, especially Europe, for most of the Pleistocene. The last two species of Stephanorhinus – Merck's rhinoceros (S. kirchbergensis) and the narrow-nosed rhinoceros (S. hemitoechus) – went extinct during the latter half of the last glacial period. The taxonomic history of Stephanorhinus is long and convoluted, as many species are known by numerous synonyms and different genera – typically placed in Rhinoceros and Dicerorhinus – for the 19th and most of the early 20th century. The genus was named by Miklós Kretzoi in 1942. The first part of the name, Stephano-, honours Stephen I, the first king of Hungary (the describer, Kretzoi, was Hungarian). The second part is from rhinos (Greek for "nose"), a typical suffix of rhinoceros genus names. Genomes obtained from Stephanorhinus kirchbergensis suggests that Stephanorhinus is more closely related to Dicerorhinus (which contains the living Sumatran rhinoceros) and Coelodonta (which contains the woolly rhinoceros), than it is to other living rhinoceroses, and is more closely related to Coelodonta than to Dicerorhinus, with the date of divergence between Coelodonta and Stephanorhinus estimated at around 5.5 million years ago, with the estimated split between their last common ancestor and Dicerorhinus estimated at around 9.4 million years ago. The genus is also closely related to the fossil rhinoceros genera Dihoplus and Pliorhinus, known from the Late Miocene and Pliocene of Eurasia, which may be ancestral to Stephanorhinus. Although a 2019 study based on dental proteomes suggested that the genus was paraphyletic with respect to Coelodonta, later studies have consistently recovered Stephanorhinus as monophyletic.