Nasutoceratops: the big-nosed horned dinosaur

Nasutoceratops was a horned dinosaur from the southern part of Laramidia, the western landmass of North America during the Late Cretaceous. Its name, often rendered as “big-nosed horned face”, points to the unusually deep and broad nasal region of its skull. The animal is also recognizable by long brow horns that curve outward and forward. Its head brings together features that make it unlike the better-known Triceratops: the skull has no large nasal horn, while the brow horns are long and sweeping rather than short and upright.

Quick facts

Discovery in the Kaiparowits Formation

The principal specimen, UMNH VP 16800, was collected in 2006 by a field team working in the Kaiparowits Formation of southern Utah. The locality lies within the Grand Staircase region, where Late Cretaceous rocks preserve a rich record of dinosaurs, other vertebrates, plants and ancient soils. Field collecting and preparation took years; the fossils were first described as a new genus and species in 2013 by Eric Lund, Scott Sampson, Mark Loewen and colleagues. A fuller account of the anatomy and variation in the preserved bones followed in 2016.

The holotype is not a complete skeleton. It preserves much of the skull, including the distinctive facial and frill bones, together with parts of the postcranial skeleton. As with many ceratopsid specimens, some elements are incomplete, displaced or reconstructed for display. The scientific diagnosis therefore rests on a combination of actual bone surfaces and anatomical relationships, not on every detail visible in a mounted skeleton. The specimen is curated in the collections of the Natural History Museum of Utah.

The genus name combines a reference to the large nose with the Greek keras, horn, and ops, face. The species name titusi honours Alan Titus, a paleontologist whose work in the monument contributed to the discovery and study of the fossil. The name is not a claim that the animal had a particularly strong sense of smell: the function of the expanded nasal region remains uncertain.

Age and the world of Laramidia

The fossil comes from the Kaiparowits Formation, a thick sequence of river, floodplain and coastal-plain deposits laid down during the Campanian stage of the Late Cretaceous. Radiometric dates and stratigraphic relationships place the formation broadly around 76 to 74 million years ago, though individual beds have narrower age ranges. The formation was part of a lowland landscape on Laramidia, west of the inland seaway that divided North America for much of this interval.

Kaiparowits rocks record shifting rivers, muddy floodplains, ponds and vegetated wetlands under a warm climate. Fossils from the formation include other horned dinosaurs, duck-billed dinosaurs, tyrannosaurs, ankylosaurs, turtles, crocodile relatives, fish and plants. These remains do not all come from precisely the same place or moment, so a species list is not a photograph of one community. It does show that the region supported a diverse terrestrial ecosystem with many large herbivores.

The broader western North American record contains several ceratopsid lineages whose distributions changed through time. Comparing Utah fossils with animals from Alberta and Montana helps test whether ceratopsids formed distinct northern and southern faunas, how long those differences persisted, and how sea-level and habitat shifts affected dispersal. Nasutoceratops is one data point in that larger pattern, not proof on its own of a geographic barrier or a single migration event.

A skull built around the nose and horns

The skull has a robust, expanded narial region and a relatively short face in front of the eye. The paired brow horns are among its most conspicuous features: they project laterally and sweep forward, with curved, twisted tips. Their orientation is inferred from the preserved horn cores, the bony bases that once supported a keratin covering. Soft keratin is not preserved, so the precise outline and length of the living horns cannot be read directly from the fossil.

The large nasal region includes internal cavities and openings. These spaces are part of the bony anatomy, but their function is not known. A large external nose does not automatically mean an exceptional sense of smell, because olfactory tissues sit within the head and the size of the visible nasal bones is not a direct measurement of receptor area. Airflow, display, structural support and other functions have been considered in ceratopsids, but the available Nasutoceratops material does not settle the question.

Behind the horns, the parietal and squamosal bones form a broad neck frill. Its outline is comparatively simple: the edge is scalloped and does not carry the long spikes or hooked projections seen in some relatives. The frill was a substantial bony structure, but it should not be treated as a rigid shield over the entire neck. Muscle attachments, skin and a possible keratinous margin are only partly accessible from the skeleton.

The jaws carried a ceratopsid dental battery: tightly packed tooth rows that formed shearing surfaces as individual teeth were replaced. This system suited the repeated processing of fibrous plant material. The beak at the front of the mouth is inferred from the premaxillae and related ceratopsid anatomy; no preserved fossil records the exact soft-tissue edge of the beak or the plant species eaten by this individual.

Classification and relationships

Nasutoceratops belongs to Ceratopsidae, the family of large, beaked horned dinosaurs, and is generally placed among centrosaurine ceratopsids. The 2013 description identified it as a distinctive early-branching centrosaurine. Later analyses have varied in the exact arrangement of centrosaurines, but the combination of a short, deep face, enlarged nasal region, long brow horns and frill anatomy remains useful for recognizing the genus.

A named subgroup, Nasutoceratopsini, has been proposed for Nasutoceratops and close relatives. Its membership and position depend on the character sample and phylogenetic method used. A cladogram is an evidence-based hypothesis about shared ancestry, not a ladder of progress. New fossils, revised descriptions and different ways of coding damaged or incomplete bones can change where branches appear.

Its horns invite comparisons with Centrosaurus, Styracosaurus and other centrosaurines, but resemblance in one feature does not establish the closest relationship. The frill, nasal bones, skull openings and details of the braincase and jaws all contribute to classification. This is why a carefully described partial skull can be more informative than an attractive reconstruction alone.

Body size, feeding and movement

Published reconstructions place the animal at roughly four to five metres in length. The estimate depends on how missing portions are restored and which complete relatives are used for comparison. A mass near a few tonnes has been suggested, but mass is especially sensitive to body volume, posture and the amount of soft tissue assumed. These values describe a reasonable range, not a direct measurement from a complete skeleton.

As a large quadrupedal herbivore, Nasutoceratops would have supported its weight on four limbs. Ceratopsid forelimbs were not identical to those of a modern mammal: the feet and limb joints show a distinctive posture, while the exact angle of the hands and shoulders is reconstructed from bones, trackways and biomechanical comparisons. Its teeth and beak indicate plant processing, but fossils do not identify a precise menu.

The Kaiparowits landscape offered low vegetation as well as shrubs and taller plants along rivers. The broad snout and dental battery are consistent with cropping and processing vegetation, although they cannot tell us whether an individual selected particular plant parts, fed at a particular height, or shifted its diet seasonally. Wear on teeth and the sedimentary setting provide context, but direct food remains associated with the holotype are not known.

What the ornaments can and cannot tell us

Long horns and a conspicuous frill could have been visible signals. They may have helped animals recognize members of their own species, display condition, compete with rivals or deter attackers. These possibilities are not mutually exclusive. The shape of a horn core can constrain the direction and strength of a keratin-covered horn, but it does not reveal a specific social ritual.

Functional interpretations should be separated from observations. The forward-curving horn cores and enlarged nasal bones are observable features. The suggestion that the horns were used in contests is a behavioral hypothesis; there is no preserved encounter that demonstrates how Nasutoceratops fought. Similarly, a frill may have contributed to display, but its size alone cannot establish that display was its primary role.

Growth also complicates comparisons. Ceratopsid skull ornament changed during development in several species, and a single individual cannot show the full range from juvenile to adult. The maturity of the holotype is estimated from skeletal features, yet the limited sample means that a complete growth series for this genus is not available. Future fossils could reveal whether horn length, nasal shape or frill proportions varied with age or between individuals.

Why Nasutoceratops matters

The animal adds a distinctive combination of anatomy to the Campanian record of southern Laramidia. It shows that centrosaurines were not all variations on one familiar horn-and-frill pattern: some had enlarged nasal regions and long, forward-sweeping brow horns while retaining a relatively plain frill edge. Its discovery also improved comparisons among ceratopsids from different parts of western North America.

At the same time, the limits of the specimen matter. We know the genus from a small number of remains compared with animals represented by many skeletons. Estimates of body mass, the function of its nose, the exact color or covering of its horns, and the details of its social behavior remain uncertain. A sound account keeps the unusual bones in view while resisting the temptation to turn every feature into a settled story.

For readers comparing horned dinosaurs, the dinosaur catalogue places Nasutoceratops alongside other profiles and lets the differences in skull shape and classification be explored across the group.