Nasutoceratops is a genus of ceratopsid dinosaur that lived in North America during the Late Cretaceous period, about 76.0–75.5 million years ago. The first known specimens were discovered in Utah in the Kaiparowits Formation of the Grand Staircase–Escalante National Monument (GSENM) from 2006 onwards, including a subadult skull with both a partial postcranial skeleton and rare skin impressions, and two other partial skulls. In 2013, the subadult was made the holotype of the new genus and species Nasutoceratops titusi; the generic name means "large-nosed horned face", and the specific name honors the paleontologist Alan L. Titus for his work at the GSENM. The dinosaur was noted for its large nose in news reports, and later featured in Jurassic World films.
The holotype skull of Nasutoceratops is approximately long; its body length has been estimated at , and its weight at . Nasutoceratops is distinct in features such as the snout region being unusually deep but short from front to back, with the external nostril forming 75% of the skull length in front of the eye sockets. The nasal bones were possibly pneumatized (air-filled), which is unknown in other ceratopsids. Its nasal horn is low and blade-like while the brow horns point forward and are approximately 40% of the total skull length; they are up to , the longest known of any centrosaurine, and have been likened to those of a Texas Longhorn bull. The is almost circular with its widest point at the middle. The on the margins of the frill are shaped like low crescents, and there is one at the midline at the top of the frill, unlike in other centrosaurines. Nasutoceratops was a basal (early diverging) member of Centrosaurinae, and may have formed a distinct clade within this group, Nasutoceratopsini, with its closest relatives.
The function of the deep front of the skull of Nasutoceratops is unknown, but may have been related to mastication. The functions of ceratopsian frills and horns have been debated, and include signalling, combat, and species recognition. The forward oriented brow horns of Nasutoceratops may have enabled interlocking with opponents, as in modern bovids. The Kaiparowits Formation dates to the late Campanian age and was deposited on Laramidia, an island continent, when North America was divided at the center by the Western Interior Seaway. This environment was dominated by wetlands and supported a diverse fauna, including other ceratopsians. Based in part on the relationship between Nasutoceratops and other centrosaurines from around the same time, it has been proposed that Laramidia was divided into dinosaur "provinces" with separate endemic species, but this has been contested.
Discovery and naming
Since 2000, the Natural History Museum of Utah (UMNH) and the Bureau of Land Management have been conducting paleontological surveys of the Kaiparowits Formation at the Grand Staircase–Escalante National Monument (GSENM) in southern Utah. This national monument was established in 1996 in part for the preservation and study of its fossils, and the surveys there have yielded a wide array of unique dinosaur fossils. Field crews from other institutions have also participated, and the collaborative effort is known as the Kaiparowits Basin Project. Among the discoveries that have been made are three new ceratopsian (horned dinosaur) taxa, one of which was identified from UMNH Locality VP 940 discovered by the then graduate student and technician Eric K. Lund during the 2006 field season. Prior to this project, the only ceratopsian remains found in the formation were uninformative, isolated teeth, and centrosaurines were known almost exclusively from the northern part of western North America.
Excavated fossils of the new ceratopsian were transported to the UMNH, where the blocks were prepared by volunteers with pneumatic air scribes and needles and subsequently reassembled; it took a few years for the team to assemble the skull of this dinosaur. It was preliminarily referred to as "Kaiparowits new taxon C" and identified as a centrosaurine (the first member of this ceratopsid group known from the formation) in 2010, and as "Kaiparowits centrosaurine A" in 2013. Three specimens of this dinosaur were collected; UMNH VP 16800 in 2006, and UMNH VP 19469 and UMNH VP 19466 in subsequent years.
The paleontologists Scott D. Sampson, Lund, Mark A. Loewen, Andrew A. Farke, and Katherine E. Clayton briefly described and scientifically named the new genus and species Nasutoceratops titusi in 2013, with specimen UMNH VP 16800 as the holotype (on which the scientific name is based). The generic name is derived from the Latin word nasutus meaning "large-nosed", and ceratops, which means "horned face" in Latinized Greek. The specific name titusi is an eponym that honors the paleontologist Alan L. Titus for his important efforts in recovering fossils from the GSENM. Lund had informally used the spelling Nasutuceratops for this dinosaur in his 2010 thesis wherein he also described it. In 2016, Lund, Sampson, and Loewen published a more detailed description of the preserved fossil material.
The holotype specimen UMNH VP 16800 consists of a partial, associated, and nearly complete skull that preserves most of the . The specimen has been interpreted as being a subadult, based on the degree of fusion of skull elements and bone surface texture. It was collected with an articulated and almost complete left forelimb, an associated yet very fragmentary right forelimb (both lacking hand bones), much of the pectoral girdle, an almost complete (the three first neck vertebrae fused together), three associated but fragmentary (of the back), as well as three patches of skin impressions associated with the left forelimb (the only ceratopsid skin impressions known from the GSENM and some of the few known worldwide). Two specimens from other quarries were assigned due to shared features with the holotype: specimen UMNH VP 19466, a disarticulated adult skull consisting of the partial right and left (which form much of the upper jaw), a right (tooth-bearing bone of the upper jaw) and right (the largest bone at the top of the snout), and specimen UMNH VP 19469, an isolated (which formed part of the side of the at the back of the skull) of a subadult. Taken together, these specimens represent about 80% of the skull and about 10% of the postcranial skeleton.
A spate of ceratopsian discoveries were made in the early 21st century, when many new taxa were named; a 2013 study stated that half of all valid genera were named since 2003, and the decade has been called a "ceratopsid renaissance". Sampson and colleagues stated that understanding of centrosaurine evolution had greatly increased in the years leading up to 2013, with 12 out of 17 known taxa having been described in the prior decade alone. In the UMNH press release accompanying the description of Nasutoceratops, the large nose of the dinosaur was emphasized, with Sampson calling it a "jumbo-sized schnoz". This was reflected in news outlets, with one article titled "paleontologists discover, mock, new dinosaur species", and another including humorous poems about the dinosaur by columnist Alexandra Petri, such as: "Higgledy piggledy, Nasutoceratops, Long-nosed horned just-unearthed dino du jour, Probably used its horns, For showing dominance, During its courtship (although we're not sure)". Nasutoceratops was featured in the 2019 Jurassic World short film Battle at Big Rock and the 2022 feature film Jurassic World Dominion, in what a UMNH article called a "pivotal role". Colin Trevorrow, the director of the former film, called Nasutoceratops "a beautiful herbivore that feels like a Texas Longhorn" (a breed of cattle).
Description
The subadult holotype skull of Nasutoceratops is approximately long. Nasutoceratops is estimated to have been long and to have weighed . As a centrosaurine ceratopsid, it would have been a large bodied, quadrupedal dinosaur with a huge skull, a hooked upper beak, a heavily constructed skeleton, a shortened, down-swept tail, a large pelvis indicating powerful muscles, and short digits. Nasutoceratops had three horns; the nasal horn above the nasal opening and the brow horns above the eye sockets. As is general for ceratopsians, it had (accessory ossifications) on the margins of the neck frill (episquamosals and epiparietals) and on the cheeks (epijugals). Their external texture was very vascularized and rugose, and they were most likely covered by a keratinous sheath when the dinosaur was alive.
Skull
The front part of the skull of Nasutoceratops is unusually deep from top to bottom, especially around the nostril area, similar to that of Diabloceratops. The external nostril forms 75% of the skull length in front of the eye sockets, more than in other ceratopsians. The snout region is almost circular overall, which is typical of centrosaurines, but it differs from more derived (or "advanced") centrosaurines and is more similar to the basal (early diverging) Diabloceratops in that it expands upwards, giving the snout region a bulbous appearance. The shortness of the snout is a result of the abbreviated nasal and maxilla bones, and it may be the shortest of any centrosaurine. The (a bone unique to ceratopsians, which forms the upper beak and contacts the front part of the premaxilla) is not preserved in Nasutoceratops, but by inferring from the contact area of the premaxilla behind it, it has been interpreted as triangular in side view, similar to centrosaurines and unlike chasmosaurines (the other main group of ceratopsids). The deep, thin, and rounded septum at the front of the premaxilla appears to be more extensive than in any other ceratopsid, and extends hindwards to underlie the horn core of the nasal.
A short hard palate is present on the premaxilla, a feature otherwise only seen in Pachyrhinosaurus among centrosaurines. Nasutoceratops differs from other ceratopsids in that the dorsal ascending ramus (upwards directed portion of bone) of the maxilla has a thin-walled contact surface for the hindwards projecting process of the premaxilla. The contact surface of the maxilla for the premaxilla is very expanded (forming a contact shelf), and has a deeply excavated sulcus (groove), unlike in other ceratopsids. Each maxilla is estimated to have contained 29 teeth, but it has not been determined whether they were double-rooted as in other ceratopsids or single-rooted as in neoceratopsians. The maxillary teeth have nearly vertical wear facets on their inwards surfaces, as is typical of ceratopsids. The tooth row is displaced downward in relation to the front part of the maxilla where it contacts the premaxilla, unlike in most ceratopsids, but similar to Diabloceratops, Avaceratops, and more basal neoceratopsians. The maxillary flange at the front of the maxilla, which contributes to the hard palate by slotting into the premaxilla, is double-socketed, a unique feature of Nasutoceratops. The back of the maxilla has a somewhat well-developed excavation on the side towards the "cheek", which seems to be less defined than in other ceratopsids.