Monoclonius

• North America

Monoclonius is a controversial genus of bird Beck dinosaurs from the group of Ceratopsidae.

There are numerous fossils that were performed under the name " Monoclonius ", many of which are often poorly preserved single bone. Most finds are now other genera, such Centrosaurus or Styracosaurus slammed or regarded as nomina dubia, which means they are too sparse for an accurate systematic classification.

The still run as Monoclonius genus with the single species M. crassus is characterized by a thin neck plate, the edge of which was in contrast to other Centrosaurinae smooth and not provided with horns. However, the findings derived from immature animals, and because the diagnostic features in the construction of the horns and the neck shield showed in the Ceratopsidae only in adult animals, it is conceivable that they are juveniles of another, already known genus in Monoclonius. Some authors consider Monoclonius therefore generally considered invalid name. The often found representation with a long nose horn comes from a fund that is now attributed to Styracosaurus.

Monoclonius was one of the oldest known Ceratopsidae, it was first described by Edward Drinker Cope in 1876. The findings are from the Judith River Group in the U.S. state of Montana, possible further finds come from Alberta ( Canada). The genus name means " branch " or " an offshoot " and does not play on the nose horn, but on the construction of the teeth on. The finds are (late Campanian ) dated to the Late Cretaceous to an age of about 75 million years.