Menefeeceratops

''Menefeeceratops'' (meaning "Menefee Formation horned face") is a genus of ceratopsid dinosaur from the Menefee Formation in New Mexico, United States. It is potentially the oldest known member of the ceratopsids, as well as the centrosaurine subfamily, related to animals including '' Yehuecauhceratops'' and '' Crittendenceratops''. The type and only species is ''Menefeeceratops sealeyi,'' known from a partial, non-articulated skeleton.

Discovery and naming

The holotype, NMMNH P-25052, of ''Menefeeceratops'' was discovered by Paul Sealey in 1996 and later mentioned in a paper in 1997,. but was not given a name until it was revisited in 2021 by Sebastian Dalman, Peter Dodson, and colleagues. The holotype was collected at the NMMNH locality 3033 in Sandoval County, New Mexico, USA, whose rocks came from the early Campanian rocks of the Allison Member of the Menefee Formation. The holotype was later collected by the New Mexico Museum of Natural History with permission of the Bureau of Land Management, who owned the land the fossils were found on, and consisted of a fragmentary skull, mandible, several fragmentary vertebrae, some ribs, the left ilium, and several fragmentary limb elements. ''Menefeeceratops'' is the only Centrosaurine described from New Mexico, while many Chasmosaurines such as ''Pentaceratops'' and ''Sierraceratops'' having been described from the late Campanian and Maastrichtian.

''Menefeeceratops'' is named from the location where the fossils were found, and in honor of Paul Sealey, the research associate at the NMMNH who originally discovered them in 1996.

Description

Based on comparisons with related animals including ''Styracosaurus'', ''Vagaceratops'', and '' Centrosaurus'', ''Menefeeceratops'' is believed to have been approximately long in life.

Paleoenvironment

The disarticulated holotype of ''Menefeeceratops'' was collected in a greenish-gray mudstone alongside an isolated trionychid turtle costal and fragments of fossilized woods. The Menefee Formation represents a widespread alluvial floodplain and consists of mudstone, siltstone, sandstone, and coal. The sandstones that comprise the Menefee Formation that are fixed within carbonaceous shales of coastal swamp or lagoon origin and are thought to have been created by flood tidal deltas that north and east across New Mexico and towards the retreating Western Interior Seaway.

''Menefeeceratops'' was contemporaneous with an indeterminate ankylosaur, the indeterminate nodosaurid '' Invictarx'', an indeterminate hadrosaurid,Hunt, Adrian P.; Lucas, Spencer G. (1993). "Cretaceous vertebrates of New Mexico". In Lucas, S.G.; Zidek, J. (eds.). ''Dinosaurs of New Mexico''. New Mexico Museum of Natural History and Science Bulletin, 2. Albuquerque, New Mexico: New Mexico Museum of Natural History and Science. pp. 77–91. the brachylophosaurin hadrosaurid '' Ornatops'', the tyrannosaurid ''Dynamoterror,'' an indeterminate tyrannosaurid, and a dromaeosaurid similar to ''Saurornitholestes''. Non-dinosaur taxa contemporaneous with ''Menefeeceratops'' include an indeterminate crocodylian, the alligatoroids ''Brachychampsa'' and '' Deinosuchus'', an indeterminate baenid turtle, an indeterminate turtle, and an indeterminate trionychid turtle.

See also

* Timeline of ceratopsian research

References

{{Taxonbar, from=Q106797815

Centrosaurines
Campanian genus first appearances
Campanian genus extinctions
Late Cretaceous dinosaurs of North America
Fossil taxa described in 2021
Ornithischian genera