Post by DinosaurMichael on Mar 25, 2012 9:36:16 GMT -5
Songhua River Mammoth - Mammuthus sungari
Mammuthus sungari, sometimes called the Songhua River Mammoth, evolved from smaller Siberian mammoths and occurred in Northern China during the middle Pleistocene (about 280,000 years ago). It survived until the beginning of the Late Pleistocene. The replica specimen on display at the Ibaraki Nature Museum in Ibaraki, Japan is 9.1 metres (30 ft) long, 5.3 metres (17 ft) tall, and has an estimated weight of 17 tonnes (19 short tons)- slightly smaller than Paraceratherium, the largest known land mammal. The original skeleton is at the Inner Mongolian Museum and it is based on two very large individuals found in 1980 at the Zhalainuoer Coal Mine in Hulun Buir City. These specimens indicate that it is the largest mammoth species found. M. sungari was described by Zhou, M.Z in 1959. Wei et al. (2010), who restudied the fossils referred to M sungari, considered this species to be a junior synonym of Mammuthus trogontherii (the steppe mammoth). The authors state that some of the fossils originally referred to M. sungari are referrable to M. trogontherii, while the others (such as the skeleton from Zhaoyuan County, Heilongjiang) can be referred to Mammuthus primigenius (the woolly mammoth), according to morphological characters and measurements.
Eotriceratops - Eotriceratops xerinsularis
Eotriceratops (meaning "early Triceratops") is a genus of ceratopsian dinosaur which lived during the late Cretaceous period. Its fossils have been found in the uppermost Horseshoe Canyon Formation, dating to about 67.6 million years ago. Its skull is reported to have been around 3 metres (10 ft) long. It has been estimated that it had a total length of about 9 meters (30 ft). Eotriceratops was described by Xiao-Chun Wu, Donald B. Brinkman, David A. Eberth and Dennis R. Braman in 2007 and the type species is E. xerinsularis. Eotriceratops is known from a single incomplete skeleton found disarticulated in Dry Island Buffalo Jump Provincial Park in southern Alberta, Canada. The skeleton consisted of a partial skull including parts of the frill, large horns above the eyes, and a small horn above the nose, similar to the closely related Triceratops. Several neck and back vertebrae, as well as several ribs, were also recovered. Because the specimen was found in weakly bedded shale, many of the bones were badly crushed. It differs from other chasmosaurine ceratopsians in unique features of the skull bones, such as an unusually pronounced jugal horn and extremely elongated, flattened and spindly epoccipitals (the bones lining and often protruding from the edge of the frill), similar to Torosaurus utahensis. Most distinctively, Eotriceratops had a pronounced vertical process on its premaxilla where it contacted the nasal bones not seen in its relatives; though some Triceratops specimens have a similar process, it is not as tall. The horns above the eyes were forward-curving and about 80 centimetres (2.6 ft) long. There appeared to have been bite marks above the eye, near the base of the left horn.
Mammuthus sungari, sometimes called the Songhua River Mammoth, evolved from smaller Siberian mammoths and occurred in Northern China during the middle Pleistocene (about 280,000 years ago). It survived until the beginning of the Late Pleistocene. The replica specimen on display at the Ibaraki Nature Museum in Ibaraki, Japan is 9.1 metres (30 ft) long, 5.3 metres (17 ft) tall, and has an estimated weight of 17 tonnes (19 short tons)- slightly smaller than Paraceratherium, the largest known land mammal. The original skeleton is at the Inner Mongolian Museum and it is based on two very large individuals found in 1980 at the Zhalainuoer Coal Mine in Hulun Buir City. These specimens indicate that it is the largest mammoth species found. M. sungari was described by Zhou, M.Z in 1959. Wei et al. (2010), who restudied the fossils referred to M sungari, considered this species to be a junior synonym of Mammuthus trogontherii (the steppe mammoth). The authors state that some of the fossils originally referred to M. sungari are referrable to M. trogontherii, while the others (such as the skeleton from Zhaoyuan County, Heilongjiang) can be referred to Mammuthus primigenius (the woolly mammoth), according to morphological characters and measurements.
Eotriceratops - Eotriceratops xerinsularis
Eotriceratops (meaning "early Triceratops") is a genus of ceratopsian dinosaur which lived during the late Cretaceous period. Its fossils have been found in the uppermost Horseshoe Canyon Formation, dating to about 67.6 million years ago. Its skull is reported to have been around 3 metres (10 ft) long. It has been estimated that it had a total length of about 9 meters (30 ft). Eotriceratops was described by Xiao-Chun Wu, Donald B. Brinkman, David A. Eberth and Dennis R. Braman in 2007 and the type species is E. xerinsularis. Eotriceratops is known from a single incomplete skeleton found disarticulated in Dry Island Buffalo Jump Provincial Park in southern Alberta, Canada. The skeleton consisted of a partial skull including parts of the frill, large horns above the eyes, and a small horn above the nose, similar to the closely related Triceratops. Several neck and back vertebrae, as well as several ribs, were also recovered. Because the specimen was found in weakly bedded shale, many of the bones were badly crushed. It differs from other chasmosaurine ceratopsians in unique features of the skull bones, such as an unusually pronounced jugal horn and extremely elongated, flattened and spindly epoccipitals (the bones lining and often protruding from the edge of the frill), similar to Torosaurus utahensis. Most distinctively, Eotriceratops had a pronounced vertical process on its premaxilla where it contacted the nasal bones not seen in its relatives; though some Triceratops specimens have a similar process, it is not as tall. The horns above the eyes were forward-curving and about 80 centimetres (2.6 ft) long. There appeared to have been bite marks above the eye, near the base of the left horn.
