Eotriceratops
Encyclopedia
Eotriceratops 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.
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.
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of ceratopsian dinosaur
Dinosaur
Dinosaurs are a diverse group of animals of the clade and superorder Dinosauria. They were the dominant terrestrial vertebrates for over 160 million years, from the late Triassic period until the end of the Cretaceous , when the Cretaceous–Paleogene extinction event led to the extinction of...
which lived during the late Cretaceous
Cretaceous
The Cretaceous , derived from the Latin "creta" , usually abbreviated K for its German translation Kreide , is a geologic period and system from circa to million years ago. In the geologic timescale, the Cretaceous follows the Jurassic period and is followed by the Paleogene period of the...
period. Its fossils have been found in the uppermost Horseshoe Canyon Formation
Horseshoe Canyon Formation
The Horseshoe Canyon Formation is part of the Edmonton Group and is up to 230m in thickness. It is Late Campanian to Early Maastrichtian in age and is composed of mudstone, sandstone, and carbonaceous shales...
, dating to about 67.6 million years ago. Its skull
Skull
The skull is a bony structure in the head of many animals that supports the structures of the face and forms a cavity for the brain.The skull is composed of two parts: the cranium and the mandible. A skull without a mandible is only a cranium. Animals that have skulls are called craniates...
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
2007 in paleontology
-newly named:-New taxa:-Newly named non-avian dinosaurs:Data courtesy of George Olshevky's dinosaur genera list.-Newly named birds:-New papers:...
and the type species
Type species
In biological nomenclature, a type species is both a concept and a practical system which is used in the classification and nomenclature of animals and plants. The value of a "type species" lies in the fact that it makes clear what is meant by a particular genus name. A type species is the species...
is E. xerinsularis.
Description
Eotriceratops is known from a single incomplete skeleton found disarticulated in Dry Island Buffalo Jump Provincial ParkDry Island Buffalo Jump Provincial Park
Dry Island Buffalo Jump Provincial Park is a provincial park in Central Alberta, Canada, located about southeast of Red Deer and east of Trochu. The park is situated along the Red Deer River and features badlands topography...
in southern Alberta
Alberta
Alberta is a province of Canada. It had an estimated population of 3.7 million in 2010 making it the most populous of Canada's three prairie provinces...
, Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
. 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
Shale
Shale is a fine-grained, clastic sedimentary rock composed of mud that is a mix of flakes of clay minerals and tiny fragments of other minerals, especially quartz and calcite. The ratio of clay to other minerals is variable. Shale is characterized by breaks along thin laminae or parallel layering...
, 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
Torosaurus
Torosaurus is a genus of ceratopsid dinosaur that lived during the late Cretaceous period , between 70 and 65 million years ago. It possessed one of the largest skulls of any known land animal. The frilled skull reached in length...
. 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.