[D] Monoclonius recurvicornis [Su]
Describer
Cope, 1889
Time
Cretaceous Late Campanian
Classification
Ornithischia Genasauria Cerapoda Marginocephalia Ceratopia Neoceratopia Nomina Dubia
Diet
Herbivore
Fossilsite
Judith River Formation (Wedge), Montana, US
Info
Skull
Braincase, 3 horns, isolated fragments.
The generic name of Monoclomius recurvicornis (based on 3 horn, a braincase, and an occipital condylum from a subadult) is probably in need to be renamend because it differs from Monoclonius. \\\\\\\"M.\\\\\\\" recurvicornis is often regarded as an indeterminate ceratopsid, however this fragmentary holotype has intriguing and unique characters.
The shape and dimension of the horns are verry different compared to other centrosaurine or chasmosaurine. The horns are 210 mm high, completely erect, and slighty procurved, totally different from Chasmosaurus (the only chasmosaurine with short supraorbital horn).
The orbital horn appear to be born from a separate center of ossification (this feature would be unique in ceratopsian kingdom). The nasal horn is a small version to that of Einiosaurus, and like other subadult centrosaurine, the horn is split in two halves. In front of right eyes there is an unespected formation: a small procurved hornlet; the left side is not preserved.
The combination of character (moderately erect suprahorbital horn, medium sized, strongly procurved nasal horn and maybe an extra pair of small hornlets in the frontal) are not comparable to any known ceratopsid taxa, and probably are diagnostic at generic level.
Cope, 1889
Time
Cretaceous Late Campanian
Classification
Ornithischia Genasauria Cerapoda Marginocephalia Ceratopia Neoceratopia Nomina Dubia
Diet
Herbivore
Fossilsite
Judith River Formation (Wedge), Montana, US
Info
Skull
Braincase, 3 horns, isolated fragments.
The generic name of Monoclomius recurvicornis (based on 3 horn, a braincase, and an occipital condylum from a subadult) is probably in need to be renamend because it differs from Monoclonius. \\\\\\\"M.\\\\\\\" recurvicornis is often regarded as an indeterminate ceratopsid, however this fragmentary holotype has intriguing and unique characters.
The shape and dimension of the horns are verry different compared to other centrosaurine or chasmosaurine. The horns are 210 mm high, completely erect, and slighty procurved, totally different from Chasmosaurus (the only chasmosaurine with short supraorbital horn).
The orbital horn appear to be born from a separate center of ossification (this feature would be unique in ceratopsian kingdom). The nasal horn is a small version to that of Einiosaurus, and like other subadult centrosaurine, the horn is split in two halves. In front of right eyes there is an unespected formation: a small procurved hornlet; the left side is not preserved.
The combination of character (moderately erect suprahorbital horn, medium sized, strongly procurved nasal horn and maybe an extra pair of small hornlets in the frontal) are not comparable to any known ceratopsid taxa, and probably are diagnostic at generic level.