Stephanorhinus kirchbergensis, commonly known as Merck's rhinoceros, is an extinct species of rhino known from the Middle to Late Pleistocene of Eurasia. One of the last members of the genus Stephanorhinus, it is considered to be a typical component of the interglacial Palaeoloxodon large faunal assemblage in Europe. Among extant species of rhinoceroses it is most closely related to the Sumatran rhinoceros, while the well known woolly rhinoceros was another close relative. In the western part of its range, it was sympatric with Stephanorhinus hemitoechus.
Merck's rhinoceros
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Scientific classification | |||||
Kingdom: | Animalia | ||||
Phylum: | Chordata | ||||
Class: | Mammalia | ||||
Order: | Perissodactyla | ||||
Family: | Rhinocerotidae | ||||
Genus: | †Stephanorhinus | ||||
Species: | †S. kirchbergensis | ||||
Binomial name | |||||
†Stephanorhinus kirchbergensis
Jäger, 1839 | |||||
Conservation Status | |||||
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Etymology and Taxonomy[]
The first part of the genus name is derived from that of King Stephen I of Hungary, and the second part from 'rhinos' (ρινος, meaning "nose"), as with Dicerorhinus. The species name was given by Georg Friedrich von Jäger in 1839 for Kirchberg an der Jagst in Baden-Württemberg, Germany where the type specimens had been found. It is often known in English (and equivalents in other languages) as Merck's rhinoceros after Carl Heinrich Merck, who gave the initial name to the species in 1784 as Rhinoceros incisivus, that is now considered a nomen oblitum, and who after a widely used junior synonym of the species, Rhinoceros/Dicerorhinus mercki (historically several alternate spellings) was named by Johann Jakob Kaup in 1841.
Origin[]
The origin of the species is obscure, with various authors suggesting either a European or Asian origin. The earliest definitive records are from Choukoutien Locality 13, in Fangshan District near Beijing at around the Early-Middle Pleistocene transition, though the older records of Stephanorhinus lantianensis and Stephanorhinus yunchuchenensis have been suggested to be synonyms of S. kirchbergensis by some sources. It appears in Europe during the early Middle Pleistocene between 0.7 and 0.6 million years ago, existing alongside the already present S. hundsheimensis. A complete mitochondrial genome obtained from a permafrost specimen and proteome studies suggest that it is more closely related to the Woolly rhinoceros than the Sumatran rhinoceros, but its relationship to other Stephanorhinus species remains unclear.
Range
Its range spans from Europe to East Asia, but appears to be absent from the Iberian Peninsula. It is presumed to have had a preference for closed forest and woodland habitats, as opposed the to open grassland habitats favoured by S. hemitoechus. Its range extended into the Arctic Circle, with a 70–48 thousand-year-old skull known from arctic Yakutia in the Chondon River valley and a late Middle Pleistocene aged lower jaw from the Yana River valley. Teeth are known from caves in Primorsky Krai , suggested to date between 50,000 and 25,000 years ago based on dates of other bones found in the deposit, which are the easternmost known records. A tooth of S. cf. kirchbergensis of an unknown age is known from the Lut Desert in eastern Iran. It is fairly common throughout the Pleistocene in North China, but is a rarer component of South Chinese assemblages, being known from around 30 localities in the region. Antoine (2012) states that D. choukoutienensis, D. lantianensis, and D. yunchuchenensis are local names for the taxon, without elaboration. Its range was strongly controlled by glacial cycles, with the species experiencing repeated cycles of expansion and contraction as the ice sheets advanced, this accounts for the relative rarity of its remains in comparison to the woolly rhinoceros. The species' range underwent significant reduction during the Last Glacial Period, with the youngest records from Italy being in Marine isotope stage (MIS) 4 and 3. The youngest reliable records in China are from the Rhino Cave in Hubei, which is early Late Pleistocene in age. Though less definitive remains are known from near Harbin in Heilongjiang, which are thought to be 20 kya in age. Records from Migong Cave just south of the Yangtze River in the Three Gorges area are suggested to date to MIS 2 (29,000-14,000 years ago). Radiocarbon dated remains from the Altai date to around 40,000 years ago.
Diet[]
Merck's rhinoceros has been interpreted as a browser, feeding on the branches and leaves of trees and shrubs. It had a more specialised diet than S. hundsheimensis and was clearly distinct from the grazing diet hypothesised for S. hemitoechus. Despite their morphological differences, dental wear analysis of several European S. kirchbergensis and S. hemitoechus populations were similar and indicative of mixed feeding, suggesting dietary convergence due to low habitat variability during the Pleistocene. Analysis of plant material embedded within teeth from the Neumark-Nord locality in Germany found remains of Populus (poplar or aspen) Quercus (oak), Crataegus, Pyracantha, Urtica and Nymphaea as well as indeterminate remains of Betulaceae, Rosaceae, and Poaceae. Preserved plant remains found with the teeth on the arctic Chondon skull included twigs of willow, birch and abundant larch alongside fragments of heather; sedges were notably absent. A specimen from Eemian aged deposits in Gorzów Wielkopolski in Poland had twigs of hazel, hornbeam, and Viscum, alongside fruit scales of birch, with hazel and birch dominating amongst the pollen. The pollen from a specimen found at Spinadesco in Italy was dominated by alder and willow, with a large contribution from Hippophae rhamnoides (sea buckthorn) and other shrubs.