The skull is 84.2 mm long. The holotype is possibly not from a full-grown individual. A comparison with related species indicates it might have been at 60% of its adult length.[1] Wedel estimated the total body length of Aquilops at 60 cm and its weight at 1.5 kg.[1]
The authors established some unique traits. The rostral, the bone core of the snout beak, curves downwards and has an arched keel on its top with a bump on the front. In front of the tooth row the upper jaw rim is over its total length concave in side view. The skull opening, the antorbital fenestra, is twice as long as it is tall and has a pointed rear, below the eye socket.[1]
Discovery and namingEdit
Restored skull
In 1997, paleontologist Scott Madsen found the single fossil, a partial skull, in Carbon County in southern Montana. While preparing the specimen, at first assumed to be of Zephyrosaurus, he discovered that it was a species new to science.[2]
In 2014 the type speciesAquilops americanus was named and described by Andrew Farke, W. Desmond Maxwell, Richard L. Cifelli, and Matt J. Wedel. The generic name is derived from Latinaquila, "eagle", and Greek ὤψ, ops, "face", in reference to the beaked snout. The specific nameamericanus refers to the fact that the species represents the first unequivocal very basal neoceratopsian found in America.[1]
The holotype, OMNH 34557, was found in a layer of the Cloverly Formation, dating from the middle-late Albian. It consists of a skull with lower jaws, of a subadult individual. The rear of the head and the palate are the main lacking parts.[1] The specimen was found during a 1997 expedition supported by the National Geographic Society and directed by Cifelli.
ClassificationEdit
Lower jawCloverly formation environment with Gobiconodon pursuing juvenile Aquilops while adults attempt to protect them.3D scan of the holotype cranium (click thumbnail to turn around)
Aquilops was placed in the Neoceratopsia. A cladistic analysis showed that it was positioned rather basal, below Leptoceratops in the evolutionary tree, with only Liaoceratops being more basal. A more derived position, e.g. as a leptoceratopsid or a protoceratopsid, was less likely; it was improbable that it was a ceratopsoid. The fact that the holotype was a subadult might have distorted these results because juvenile individuals often show basal traits. However, after correcting for traits that might change during ontogeny, the resulting tree was basically the same. The ceratopsians more derived than psittacosaurids, called neoceratopsians, evolved in Asia: the presence of a basal neoceratopsian in North America was seen as an indication for a late Early Cretaceous migration event, the ancestors of Aquilops invading from Asia. Two later such events would have occurred in the early Late Cretaceous.[1]
^ abcdefFarke, Andrew A.; Maxwell, W. Desmond; Cifelli, Richard L.; Wedel, Mathew J. (2014-12-10). "A Ceratopsian Dinosaur from the Lower Cretaceous of Western North America, and the Biogeography of Neoceratopsia". PLoS ONE. 9 (12): e112055. Bibcode:2014PLoSO...9k2055F. doi:10.1371/journal.pone.0112055. PMC4262212. PMID 25494182.
^Crofts, Natalie (2014-12-12). "Utah paleontologist shares tale of discovering cat-sized dinosaur". KSL.com. Salt Lake City: Deseret Digital Media. Retrieved 2014-12-23.
External linksEdit
- Interactive 3d models of Aquilops skull and dinosaur.
October 21, 2023
aquilops, early, herbivorous, ceratopsian, dinosaur, dating, from, early, cretaceous, north, america, approximately, million, million, years, type, species, americanus, temporal, range, early, cretaceous, preꞒ, skull, seen, from, sides, above, belowscientific,. Aquilops is an early herbivorous ceratopsian dinosaur dating from the Early Cretaceous of North America approximately 109 million to 104 million years ago The type species is A americanus AquilopsTemporal range Early Cretaceous 107 Ma PreꞒ Ꞓ O S D C P T J K Pg N Skull seen from the sides above and belowScientific classificationDomain EukaryotaKingdom AnimaliaPhylum ChordataClade DinosauriaClade OrnithischiaSuborder CeratopsiaInfraorder NeoceratopsiaGenus AquilopsFarke et al 2014Species A americanusBinomial name Aquilops americanusFarke et al 2014 Contents 1 Description 2 Discovery and naming 3 Classification 4 See also 5 References 6 External linksDescription Edit nbsp RestorationThe skull is 84 2 mm long The holotype is possibly not from a full grown individual A comparison with related species indicates it might have been at 60 of its adult length 1 Wedel estimated the total body length of Aquilops at 60 cm and its weight at 1 5 kg 1 The authors established some unique traits The rostral the bone core of the snout beak curves downwards and has an arched keel on its top with a bump on the front In front of the tooth row the upper jaw rim is over its total length concave in side view The skull opening the antorbital fenestra is twice as long as it is tall and has a pointed rear below the eye socket 1 Discovery and naming Edit nbsp Restored skullIn 1997 paleontologist Scott Madsen found the single fossil a partial skull in Carbon County in southern Montana While preparing the specimen at first assumed to be of Zephyrosaurus he discovered that it was a species new to science 2 In 2014 the type species Aquilops americanus was named and described by Andrew Farke W Desmond Maxwell Richard L Cifelli and Matt J Wedel The generic name is derived from Latin aquila eagle and Greek ὤps ops face in reference to the beaked snout The specific name americanus refers to the fact that the species represents the first unequivocal very basal neoceratopsian found in America 1 The holotype OMNH 34557 was found in a layer of the Cloverly Formation dating from the middle late Albian It consists of a skull with lower jaws of a subadult individual The rear of the head and the palate are the main lacking parts 1 The specimen was found during a 1997 expedition supported by the National Geographic Society and directed by Cifelli Classification Edit nbsp Lower jaw nbsp Cloverly formation environment with Gobiconodon pursuing juvenile Aquilops while adults attempt to protect them nbsp 3D scan of the holotype cranium click thumbnail to turn around Aquilops was placed in the Neoceratopsia A cladistic analysis showed that it was positioned rather basal below Leptoceratops in the evolutionary tree with only Liaoceratops being more basal A more derived position e g as a leptoceratopsid or a protoceratopsid was less likely it was improbable that it was a ceratopsoid The fact that the holotype was a subadult might have distorted these results because juvenile individuals often show basal traits However after correcting for traits that might change during ontogeny the resulting tree was basically the same The ceratopsians more derived than psittacosaurids called neoceratopsians evolved in Asia the presence of a basal neoceratopsian in North America was seen as an indication for a late Early Cretaceous migration event the ancestors of Aquilops invading from Asia Two later such events would have occurred in the early Late Cretaceous 1 Marginocephalia Pachycephalosauria StegocerasCeratopsia YinlongXuanhuaceratopsChaoyangsaurusPsittacosaurus P sinensisP mongoliensisNeoceratopsia LiaoceratopsAquilopsAuroraceratopsYamaceratopsHelioceratopsArchaeoceratopsKoreaceratopsLeptoceratopsidaeCoronosauriaSee also Edit2014 in paleontology Neoceratopsia Timeline of ceratopsian researchReferences Edit a b c d e f Farke Andrew A Maxwell W Desmond Cifelli Richard L Wedel Mathew J 2014 12 10 A Ceratopsian Dinosaur from the Lower Cretaceous of Western North America and the Biogeography of Neoceratopsia PLoS ONE 9 12 e112055 Bibcode 2014PLoSO 9k2055F doi 10 1371 journal pone 0112055 PMC 4262212 PMID 25494182 Crofts Natalie 2014 12 12 Utah paleontologist shares tale of discovering cat sized dinosaur KSL com Salt Lake City Deseret Digital Media Retrieved 2014 12 23 External links EditThe Sam Noble Museum Interactive 3d models of Aquilops skull and dinosaur Retrieved from https en wikipedia org w index php title Aquilops amp oldid 1097285611, wikipedia, wiki, book, books, library,
