There is confusion about the correct scientific name for the steppe mammoth, either Mammuthus armeniacus or Mammuthus trogontherii. Falconer used material from Asian sources while Pohlig worked with fossil remains from Europe and both names appear in scientific publications, adding to the confusion. A first taxonomical overhaul was done by Maglio who decided that both names were synonyms, armeniacus being the older, hence the preferred name. However, in Shoshani & Tassy it was decided that the description of Pohlig prevailed, and consequently the correct name for the steppe mammoth is M. trogontherii. It is unclear whether both forms are indeed identical and authors tend to use the name M. trogontherii for European material and M. armeniacus for Asian remains. Several Japanese mammoth varieties from the early Pleistocene have been named, but all are now thought to be synonyms of M. trogontherii.
Description
The steppe mammoth had a short skull compared to M. meridionalis as well as a smaller jaw. The males had spiral tusks with a recurved tip that could grow as long as in old bulls; females on the other side had thinner and slightly curved tusks. With several individuals reaching tall at the shoulders, it is smaller than the largest proboscideans ever to have lived, but was larger than other mammoths. A skeleton mounted on the Azov Museum reaches at the shoulder, though this figure might be overestimated because the vertebrae have been placed between the tips of the shoulder blades. Another individual represented by a single humerus long found in Mosbach Sande, Germany, is estimated to have an in-the-flesh shoulder height of, weighed between and might be the largest mammoth found yet. Another estimate gives a shoulder height of and a weight of for the species.
Discovery
Fossilized teeth are recovered, but skeletal parts are rare. The most complete skeleton of a steppe mammoth yet found was discovered in 1996 in Kikinda, Serbia. It was mounted, and put on display in 2005. The specimen is a female, which was about high, in length and with long tusks. Another quite complete steppe mammoth was excavated in the cliffs of West Runton in Norfolk, UK; it preserves its jaws and teeth but is missing the upper part of its skull. A rare skull found in Auvergne, France, in 2008 will be examined by Dick Mol and Frédéric Lacombat in the Musée Crozatier in Le Puy-en-Velay. In 1959 Zhou, M. Z described what he called a new species of mammoth, M. sungari, that gained recent notoriety as the largest proboscidean due to a tall and long composite skeletal mount based on two individuals found in 1980. However, Wei et al., who restudied the fossils referred to M sungari, considered this species to be a junior synonym of M. trogontherii. The authors state that some of the fossils are referrable to M. trogontherii, while the others can be referred to M. primigenius, according to morphological characters and measurements.
Evolution
M. trogontherii is derived from Mammuthus meridionalis, the oldest records of the species are known from China, at around 1.8-2 ma in age from the Nihewan Formation near Majuangou, Hebei. Steppe mammoths arrived in North America across Beringia around 1.5 million years ago, giving rise to the columbian mammoth. Steppe mammoths replaced Mammuthus meridionalis between 1-0.7 million years ago in Europe, in a complex diachronus mosaic pattern. European populations of M. trogontherii experienced a persistent size reduction towards the end of the Middle Pleistocene. A population of M. trogontherii in north east Siberia developed higher tooth plate count after 0.8 mya, reaching M. primigenius morphology by 400,000 years ago. M. primigenius replaced M. trogontherii in Europe around 200 kya. Relict populations of M. trogontherii may have persisted in Mongolia and North China well into the Last Glacial Period, with teeth of M. trogontherii like morphology in Shanxii being dated to 33.858–24.857 ka BP and Inner Mongolia to c. 33.7 ka BP.
