Horned, Frilled Dinosaur Profiles and Pictures

Meet the Horned, Frilled Dinosaurs of the Mesozoic Era

Ceratopsians—the horned, frilled dinosaurs—were some of the most common plant-eaters of the later Mesozoic Era. Explore pictures and detailed profiles of over 60 ceratopsian dinosaurs, ranging from A (Achelousaurus) to Z (Zuniceratops).

Achelousaurus

Name:

Achelousaurus (Greek for "Achelous lizard"); pronounced AH-kell-oo-SORE-us

Habitat:

Woodlands of North America

Historical Period:

Late Cretaceous (80-65 million years ago)

Size and Weight:

About 20 feet long and one ton

Diet:

Plants

Distinguishing Characteristics:

Medium size; large frill; bony knobs above eyes

Numerous bones of this horned dinosaur have been unearthed in Montana's Two Medicine Formation, but it's still not clear if this ceratopsian merits its own genus. The main thing that distinguishes Achelousaurus from its close relative, Pachyrhinosaurus, is the smaller, bony knobs over its eyes and nose; this gentle herbivore also bore a close resemblance to another ceratopsian, Einiosaurus. It remains a possibility that Achelousaurus was actually a growth stage of either Pachyrhinosaurus or Einiosaurus (or vice-versa), much as specimens of Torosaurus may actually have been superannuated Triceratops individuals.

The name Achelousaurus (pronounced with a hard "k," not like a sneeze) merits some explanation. Achelous was an obscure, shape-shifting river god of Greek mythology who had one of his horns torn off during a fight with Hercules. The name Achelousaurus refers both to this dinosaur's supposedly "missing" horns and its weird, shape-shifting mix of frills and bony knobs, compared to its fellow ceratopsians.

Agujaceratops

Name

Agujaceratops (Greek for "Aguja horned face"); pronounced ah-GOO-hah-SEH-rah-tops

Habitat

Woodlands of southern North America

Historical Period

Late Cretaceous (77 million years ago)

Size and Weight

About 15 feet long and 2 tons

Diet

Plants

Distinguishing Characteristics

Large, two-lobed frill; horns over eyes

Agujaceratops was classified as a Chasmosaurus species (C. mariscalensis) until 2006 when a re-analysis of its fragmented remains revealed some distinctive characteristics. Despite its elevation to genus status, Agujaceratops is still considered to be a close relative of Chasmosaurus, and it also had a lot in common with another ceratopsian of late Cretaceous North America, Pentaceratops.

Ajkaceratops

Name

Ajkaceratops (Greek for "Ajka horned face"); pronounced EYE-kah-SEH-rah-tops

Habitat

Woodlands of central Europe

Historical Period

Late Cretaceous (85 million years ago)

Size and Weight

About 3 feet long and 30-40 pounds

Diet

Plants

Distinguishing Characteristics

Small size; short frill

Like many dinosaurs of the Mesozoic Era, ceratopsians were restricted to two continents: North America and Eurasia. More remarkably, until the recent discovery of Ajkaceratops, the only known Eurasian ceratopsians hailed from the eastern part of the continent (one of the westernmost examples being Protoceratops, from what is now present-day Mongolia). The three-foot-long Ajkaceratops lived about 85 million years ago, fairly early in ceratopsian terms, and it seems to have been most closely related to the central Asian Bagaceratops. Some paleontologists speculate that Ajkaceratops lived on one of the numerous small islands dotting late Cretaceous Europe, which would account for its stunted size (given the relative lack of available resources).

Albalophosaurus

Name

Albalophosaurus (Greek for "white-crested lizard"); pronounced AL-bah-LOW-foe-SORE-us

Habitat

Woodlands of eastern Asia

Historical Period

Early Cretaceous (140-130 million years ago)

Size and Weight

Undisclosed

Diet

Plants

Distinguishing Characteristics

Small size; bipedal posture; thickened skull

The scattered, fragmented remains of Albalophosaurus (only a few pieces of the skull) reveal something extraordinary: a small, early Cretaceous ornithopod dinosaur "caught in the act" of evolving into one of the first basal ceratopsians. Unfortunately, pending additional fossil discoveries, there's not much else we can say about Albalophosaurus or its exact relationship to the early ceratopsians of the Asian mainland.

Albertaceratops

Name:

Albertaceratops (Greek for "Alberta horned face"); pronounced al-BERT-ah-SEH-rah-tops

Habitat:

Woodlands of North America

Historical Period:

Late Cretaceous (80-75 million years ago)

Size and Weight:

About 10 feet long and 2-3 tons

Diet:

Plants

Distinguishing Characteristics:

Long brow horns; Centrosaurus-like skull

As a result of their bizarre head ornamentation, the skulls of ceratopsians tend to preserve better in the fossil record than the rest of their skeletons. A case in point is Albertaceratops, which is represented by a single complete skull discovered in Alberta, Canada in 2001. For all intents and purposes, Albertaceratops wasn't much different from other horned, frilled dinosaurs of the late Cretaceous period, with the exception of its unusually long brow horns combined with a Centrosaurus-like skull. Based on this feature, one paleontologist has concluded that Albertaceratops is the most "basal" (earliest, simplest) ceratopsian in the Centrosaurus lineage.

Anchiceratops

Name:

Anchiceratops (Greek for "near the horned face"); pronounced ANN-chi-SEH-rah-tops

Habitat:

Woodlands of North America

Historical Period:

Late Cretaceous (70 million years ago)

Size and Weight:

About 12 feet long and 1-2 tons

Diet:

Plants

Distinguishing Characteristics:

Moderate size; paired brow horns; notched frill

At first glance, this ceratopsian (horned, frilled dinosaur) looks indistinguishable from its better-known cousin Triceratops, until you notice the small, triangular projections on the top of Anchiceratops' massive frill (which, like most such anatomical features, were probably a sexually selected characteristic).

Ever since it was named in 1914 by the famous paleontologist Barnum Brown, Anchiceratops has proven difficult to classify. Barnum himself concluded that this dinosaur was intermediate between Triceratops and the relatively obscure Monoclonius, but more recent analyses have placed it (somewhat surprisingly) closer to Chasmosaurus and another lesser known ceratopsian, Arrhinoceratops. It has even been suggested that Anchiceratops was an accomplished swimmer that enjoyed a hippopotamus-like lifestyle, a theory that has since fallen by the wayside.

Aquilops

Name

Aquilops (Greek for "eagle face"); pronounced ACK-will-ops

Habitat

Woodlands of North America

Historical Period

Middle Cretaceous (110-105 million years ago)

Size and Weight

About two feet long and 3-5 pounds

Diet

Plants

Distinguishing Characteristics

Small size; beaked snout

Ceratopsians, or horned, frilled dinosaurs, followed a unique evolutionary pattern. Tiny, cat-sized members of the breed (like Psittacosaurus) originated over 100 million years ago in Asia, during the early to middle Cretaceous period, and grew to Triceratops-like sizes by the time they reached North America in the late Cretaceous. What makes Aquilops important is that it's the first small, "Asian" ceratopsian ever to be discovered in North America, and thus represents an important link between the eastern and western branches of this populous dinosaur family. (By the way, for over a decade the type fossil of Aquilops was identified as Zephyrosaurus, a non-ceratopsian ornithopod, until a re-examination of the remains prompted this new assessment.)

Archaeoceratops

Name:

Archaeoceratops (Greek for "ancient horned face"); pronounced AR-kay-oh-SEH-rah-tops

Habitat:

Woodlands of Asia

Historical Period:

Early Cretaceous (125-115 million years ago)

Size and Weight:

About 2-3 feet long and 5-10 pounds

Diet:

Plants

Distinguishing Characteristics:

Small size; relatively large head with small frill

Over the past couple of decades, paleontologists have discovered a bewildering array of "basal" ceratopsians (horned, frilled dinosaurs) in central and eastern Asia, small, possibly bipedal herbivores that were directly ancestral to huge, lumbering beasts like Triceratops and Pentaceratops. Like its close relatives, Liaoceratops and Psittacosaurus, Archaeoceratops looked more like an ornithopod than a ceratopsian, especially considering its lithe build and stiff tail; the only giveaways were the primitive beak and frill on its slightly oversized head, the precursors of the sharp horns and giant awnings of its descendants tens of millions of years down the line.

Arrhinoceratops

Name:

Arrhinoceratops (Greek for "no-nose horned face"); pronounced AY-rye-no-SEH-rah-tops

Habitat:

Woodlands of North America

Historical Period:

Late Cretaceous (70-65 million years ago)

Size and Weight:

About 20 feet long and 2-3 tons

Diet:

Plants

Distinguishing Characteristics:

Large frill; two long horns over eyes

When its type fossil was first discovered, in Utah in 1923, Arrhinoceratops seemed to be missing the small nose horn possessed by most ceratopsians; hence its name, Greek for "no-nose horned face." Wouldn't you know it, Arrhinoceratops had a horn after all, making it a very close cousin of Triceratops and Torosaurus (which may have been the same dinosaur). This small mixup aside, Arrhinoceratops was very much like other ceratopsians of the late Cretaceous period, a four-footed, elephant-sized herbivore that likely used its long horns to battle other males for the right to mate.

Auroraceratops

Name:

Auroraceratops (Greek for "dawn horned face"); pronounced ore-ORE-ah-SEH-rah-tops

Habitat:

Woodlands of Asia

Historical Period:

Early Cretaceous (125-115 million years ago)

Size and Weight:

About 20 feet long and 1,000-2,000 pounds

Diet:

Plants

Distinguishing Characteristics:

Short, wrinkled head; flat snout

Dating to the early Cretaceous period, about 125 million years ago, Auroraceratops resembled a larger version of small, "basal" ceratopsians like Psittacosaurus and Archaeoceratops, with a minimal frill and the barest beginnings of a nasal horn. In its considerable size, however—about 20 feet from head to tail and one ton—Auroraceratops anticipated the larger, "classic" ceratopsians of the late Cretaceous period like Triceratops and Styracosaurus. It's conceivable that this plant-eater occasionally walked on two legs, but definitive evidence for this is lacking.

Avaceratops

Name:

Avaceratops (Greek for "Ava's horned face"); pronounced AY-vah-SEH-rah-tops

Habitat:

Woodlands of North America

Historical Period:

Late Cretaceous (80-70 million years ago)

Size and Weight:

About 13 feet long and one ton

Diet:

Plants

Distinguishing Characteristics:

Short, thick frill; large head with powerful jaws

Named after the wife of the man who discovered its remains, Avaceratops may have been an unusually big-headed ceratopsian. The sole specimen is f a juvenile, and the babies and juveniles of most vertebrates tend to have proportionately bigger heads compared to the rest of their bodies. Because there's a lot paleontologists don't know about the growth stages of ceratopsians, it may yet turn out that Avaceratops was a species of an existing genus; as things stand, it seems to have occupied an intermediate evolutionary stage between the better-known Centrosaurus and Triceratops.

Bagaceratops

Name:

Bagaceratops (Mongolian/Greek for "small horned face"); pronounced BAG-ah-SEH-rah-tops

Habitat:

Plains of central Asia

Historical Period:

Late Cretaceous (80 million years ago)

Size and Weight:

About 3 feet long and 50 pounds

Diet:

Plants

Distinguishing Characteristics:

Small size; beaked, horned snout

Most of the ceratopsians ("horned faces") of the late Cretaceous period were gigantic, multi-ton earth-shakers like Triceratops, but millions of years earlier, in the eastern regions of Asia, these dinosaurs were much more petite. One such smaller dinosaur was Bagaceratops, which only measured about three feet long from snout to tail and weighed just 50 pounds. This fairly obscure, minimally ornamented ceratopsian ancestor is known mostly by the partial remains of various skulls; a complete skeleton has yet to be unearthed, but it's clear that Bagaceratops closely resembled the other primitive ceratopsians of the middle-to-late Cretaceous.

Brachyceratops

Name:

Brachyceratops (Greek for "short-horned face"); pronounced BRACK-ee-SEH-rah-tops

Habitat:

Woodlands of North America

Historical Period:

Late Cretaceous (75 million years ago)

Size and Weight:

About 20 feet long and one ton

Diet:

Plants

Distinguishing Characteristics:

Frilled skull with short horns

Paleontologists have only unearthed the remains of five-foot-long juveniles of this genus, and incomplete ones at that, the "type specimen" hailing from the Two Medicine Formation in Montana. Based on what has been pieced together so far, Brachyceratops appears to have been a fairly typical ceratopsian, with the massive, horned and frilled face characteristic of the breed. However, it's possible that Brachyceratops may one day be assigned as a new species of an existing genus of ceratopsian, especially if it turns out that juveniles changed their appearance as they aged.

Bravoceratops

Name

Bravoceratops (Greek for "wild horned face"); pronounced BRAH-voe-SEH-rah-tops

Habitat

Woodlands of southern North America

Historical Period

Late Cretaceous (70 million years ago)

Size and Weight

Undisclosed

Diet

Plants

Distinguishing Characteristics

Narrow snout; horns above eyes; large frill

A bewildering number of ceratopsians (horned, frilled dinosaurs) occupied North America during the late Cretaceous period, the end stage of a long evolutionary process that began a few million years earlier in eastern Asia. Among the latest to join the ranks is Bravoceratops, which was announced to the world in 2013 as a "chasmosaurine" ceratopsian closely related to Coahuilaceratops (and, of course, to the eponymous member of this breed, Chasmosaurus). As with its cousins, the broad frill of Bravoceratops may have been brightly colored during mating season, and may also have been employed as a means of intra-herd recognition.

Centrosaurus

If Triceratops means "three-horned face" and Pentaceratops means "five-horned face," a better name for Centrosaurus might have been Monoceratops (one-horned face). This otherwise standard ceratopsian was distinguished by the sole horn jutting out from its snout.

Cerasinops

Name:

Cerasinops (Greek for "lesser horned face"); pronounced SEH-rah-SIGH-nops

Habitat:

Woodlands of North America

Historical Period:

Late Cretaceous (85 million years ago)

Size and Weight:

About eight feet long and 400 pounds

Diet:

Plants

Distinguishing Characteristics:

Relatively small size; blunt head with horned beak

A mere 20 million years or so before enormous ceratopsians (horned, frilled dinosaurs) like Triceratops developed, smaller species such as t he 400-pound Cerasinops roamed North America. Although Cerasinops was nowhere near as small as "basal" ceratopsians like Psittacosaurus that preceded it by tens of millions of years, it had many anatomical characteristics in common with these early plant-eaters, including an unobtrusive frill, a prominent beak and, possibly, a bipedal posture. The closest relative of Cerasinops appears to have been Leptoceratops, but otherwise, this ceratopsian is still poorly understood.

Chaoyangsaurus

Name:

Chaoyangsaurus (Greek for "Chaoyang lizard"); pronounced CHOW-yang-SORE-us

Habitat:

Woodlands of Asia

Historical Period:

Middle-Late Jurassic (170-145 million years ago)

Size and Weight:

About three feet long and 20-30 pounds

Diet:

Plants

Distinguishing Characteristics:

Small size; bipedal posture; horned snout

Ceratopsians are often described with reference to late Cretaceous giants like Triceratops and Styracosaurus, but the fact is that these herbivores existed (in less impressive form) as far back as the late Jurassic period. Chaoyangsaurus is one of the earliest ceratopsians yet known, predating the previous record-holder, Psittacosaurus, by tens of millions of years (and just about tied with its fellow Asian horned face, Yinlong). This three-foot-long herbivore looks more like an ornithopod and is only identified as a ceratopsian thanks to the unique structure of its beak.

Chasmosaurus

Sexual selection is one possible explanation for the huge, boxy head frill of Chasmosaurus, which may have changed color to signify either sexual availability or readiness to butt heads with other males for the right to mate.

Coahuilaceratops

Name:

Coahuilaceratops (Greek for "Coahuila horned face"); pronounced CO-ah-HWEE-lah-SEH-rah-tops

Habitat:

Woodlands of North America

Historical Period:

Late Cretaceous (72 million years ago)

Size and Weight:

About 22 feet long and 2-3 tons

Diet:

Plants

Distinguishing Characteristics:

Enormous head with long, paired, curving horns

In most ways, Coahuilaceratops was a typical ceratopsian ("horned face") dinosaur of the late Cretaceous period: a slow-witted, big-headed herbivore that was the approximate size and weight of a small truck. What set this genus apart from more famous relatives like Triceratops were the paired, forward-curving horns set above its eyes, which reached a whopping four feet in length; in fact, Coahuilaceratops is the longest-horned dinosaur yet discovered. The length and shape of these appendages suggest that males of the genus may have literally "locked horns" when competing for females, much as big-horned sheep do today.

Coronosaurus

Name

Coronosaurus (Greek for "crown lizard"); pronounced core-OH-no-SORE-us

Habitat

Woodlands of North America

Historical Period

Late Cretaceous (75 million years ago)

Size and Weight

About 15 feet long and 2 tons

Diet

Plants

Distinguishing Characteristics

Moderate size; prominent horn and frill

Coronosaurus was assigned as a species of the well-known Centrosaurus (C. brinkmani) until a reexamination of its type fossil in 2012 prompted paleontologists to assign it its own genera. Coronosaurus was moderately sized as ceratopsians go, only about 15 feet long and two tons, and it seems to have been most closely related not to Centrosaurus but to Styracosaurus.

Diabloceratops

Name:

Diabloceratops (Greek for "devil horned face"); pronounced dee-AB-low-SEH-rah-tops

Habitat:

Woodlands of North America

Historical Period:

Late Cretaceous (85 million years ago)

Size and Weight:

About 20-25 feet long and 1-2 tons

Diet:

Plants

Distinguishing Characteristics:

No horn on snout; medium-sized frill with two long horns on top

Although Diabloceratops has only recently been announced to the general public, this horned dinosaur has been familiar to paleontologists ever since 2002, when its near-intact skull was discovered in southern Utah. Eight years of analysis and preparation have yielded what may (or may not) be a ceratopsian "missing link": Diabloceratops seems to have evolved from the smaller horned dinosaurs of the early Cretaceous period, yet it predated more advanced genera like Centrosaurus and Triceratops by millions of years. As you might expect given its evolutionary position, the massive head of Diabloceratops was ornamented in a unique way: it lacked a horn on its snout, but had a medium-sized, Centrosaurus-like frill with two sharp horns jutting up from either side. (It's possible that Diabloceratops' frill was covered with a thin layer of skin that changed color during mating season.)

Diceratops

Diceratops was "diagnosed" way back in 1905 on the basis of a single, two-horned skull lacking the characteristic nasal horn of Triceratops; however, some paleontologists believe this specimen was actually a deformed individual of the latter dinosaur.

Einiosaurus

Name:

Einiosaurus (Indigenous/Greek for "buffalo lizard"); pronounced AY-nee-oh-SORE-us

Habitat:

Woodlands of North America

Historical Period:

Late Cretaceous (70 million years ago)

Size and Weight:

About 20 feet long and 2 tons

Diet:

Plants

Distinguishing Characteristics:

Long, curving horn on snout; two horns on frill

Einiosaurus was distinguished from its more famous cousins (like Centrosaurus and Triceratops) by the single, downward-curving horn jutting out from the middle of its snout. The discovery of numerous bones jumbled together (representing at least 15 separate individuals) indicates that this dinosaur may have traveled in herds, at least one of which reached a catastrophic end—possibly when all the members drowned while trying to cross a flooding river.

Eotriceratops

Name:

Eotriceratops (Greek for "dawn three-horned face"); pronounced EE-oh-try-SEH-rah-tops

Habitat:

Woodlands of North America

Historical Period:

Late Cretaceous (70-65 million years ago)

Size and Weight:

About 30 feet long and three tons

Diet:

Plants

Distinguishing Characteristics:

Large size; forward-curving horns

Even as some paleontologists argue that the roster of ceratopsians (horned, frilled dinosaurs) needs to be severely trimmed—on the theory that some of these dinosaurs were actually growth stages of existing dinosaurs—others have persisted in naming new genera. A good example is Eotriceratops, which the average person would find virtually indistinguishable from Triceratops but which merits its own name thanks to some obscure anatomical features (for example, the shape of its jugal horn, epoccipitals, and premaxilla). Interestingly, the "type specimen" of Eotriceratops bears bite marks above the left eye, perhaps remnants of an encounter with a hungry Tyrannosaurus Rex.

Gobiceratops

Name:

Gobiceratops (Greek for "Gobi horned face"); pronounced GO-bee-SEH-rah-tops

Habitat:

Plains of central Asia

Historical Period:

Late Cretaceous (85 million years ago)

Size and Weight:

About three feet long and 50 pounds

Diet:

Plants

Distinguishing Characteristics:

Small size; small but thick skull

Most ceratopsians, or horned, frilled dinosaurs, are represented in the fossil record by truly massive skulls; for example, Triceratops had one of the biggest heads of any land animal that ever lived. That's not the case for Gobiceratops, which was "diagnosed" in 2008 based on the single, tiny skull of a juvenile, less than two inches wide. Not much is known about how this small, herbivorous dinosaur lived, but it seems to have been related to another early ceratopsian of central Asia, Bagaceratops, and eventually gave rise to the giant ceratopsians of North America.

Gryphoceratops

Name:

Gryphoceratops (Greek for "Griffin horned face"); pronounced GRIFF-oh-SEH-rah-tops

Habitat:

Woodlands of North America

Historical Period:

Late Cretaceous (83 million years ago)

Size and Weight:

About two feet long and 20-25 pounds

Diet:

Plants

Distinguishing Characteristics:

Small size; tough, horny jaws

Gryphoceratops, which measured a bare two feet from head to tail, didn't boast any of the elaborate ornamentations of its larger, more famous cousins. What Gryphoceratops did have in common with Triceratops and its ilk was its tough, horny beak, which it used to clip off equally tough vegetation. The smallest ceratopsian yet discovered in North America (it was dug up very close to Canada's Dinosaur Provincial Park), Gryphoceratops was closely related to the equally "basal" Leptoceratops.

Hongshanosaurus

Name:

Hongshanosaurus (Chinese/Greek for "red hill lizard"); pronounced hong-shan-oh-SORE-us

Habitat:

Woodlands of Asia

Historical Period:

Early Cretaceous (125 million years ago)

Size and Weight:

About five feet long and 30-40 pounds

Diet:

Plants

Distinguishing Characteristics:

Small size; bipedal posture; beaked snout

Hongshanosaurus was very similar to Psittacosaurus without actually being a species of Psittacosaurus: this early Cretaceous ceratopsian (horned, frilled dinosaur) was distinguished from its more famous contemporary only by the distinctive shape of its skull. Like Psittacosaurus, Hongshanosaurus didn't bear much of a resemblance to its descendants tens of millions of years down the line like Triceratops and Centrosaurus. In fact, it had many features in common with the small, two-legged ornithopods from which it evolved.

Judiceratops

Name:

Judiceratops (Greek for "Judith River horned face"); pronounced JOO-dee-SEH-rah-tops

Habitat:

Woodlands of North America

Historical Period:

Late Cretaceous (80-75 million years ago)

Size and Weight:

Undisclosed

Diet:

Plants

Distinguishing Characteristics:

Two brow horns; large frill with triangular serrations

Judiceratops was named in 2013 after the Judith River Formation in Montana where its "type fossil" was discovered. Judiceratops' claim to fame is that it's the earliest "chasmosaurine" dinosaur yet identified, ancestral to the better-known Chasmosaurus that lived a few million years later—a kinship you can instantly detect in these two dinosaurs' distinctively ornamented frills.

Koreaceratops

Name:

Koreaceratops (Greek for "Korean horned face"); pronounced core-EE-ah-SEH-rah-tops

Habitat:

Woodlands of eastern Asia

Historical Period:

Middle Cretaceous (100 million years ago)

Size and Weight:

About three feet long and 25-50 pounds

Diet:

Plants

Distinguishing Characteristics:

Small size; broad tail

Ceratopsians spanned the expanse of North America and Eurasia during the Cretaceous period, so the recent discovery of Koreaceratops in South Korea (the first ceratopsian ever to be unearthed in this country) should come as no surprise. Dating from the middle Cretaceous, about 100 million years ago, Koreaceratops was a relatively "basal" member of its breed, closely related to other early ceratopsians like Archaeoceratops and Cerasinops (and not at all resembling ornate, later ceratopsians like Triceratops).

What makes Koreaceratops especially interesting is its broad tail, which—while not an unusual feature in other early ceratopsians—has prompted some speculation about whether or not this dinosaur, and others like it, went for the occasional swim. It's more likely that early ceratopsians would have evolved wide tails as either a sexually selected characteristic (that is, males with bigger tails got to mate with more females) or as a way to dissipate or collect heat, so the aquatic hypothesis will have to remain just that pending further evidence.

Kosmoceratops

The head of the elephant-sized ceratopsian Kosmoceratops was decorated with 15 horns and horn-like structures, including a pair of large horns above the eyes vaguely resembling those of a bull.

Leptoceratops

Name:

Leptoceratops (Greek for "small horned face"); pronounced LEP-toe-SER-ah-tops

Habitat:

Plains of western North America

Historical Period:

Late Cretaceous (70-65 million years ago)

Size and Weight:

About six feet long and 200 pounds

Diet:

Plants

Distinguishing Characteristics:

Slender build; small protuberances on face

Leptoceratops is an object lesson in how "primitive" dinosaurs sometimes lived directly alongside their more evolved cousins. This ceratopsian belonged to the same family as bigger, more florid dinosaurs like Triceratops and Styracosaurus, but its facial ornamentation was on the minimal side (only a short frill and a curved lower jaw), and overall it was significantly smaller, only about six feet long and 200 pounds. In this respect, Leptoceratops was smaller even than the most common "small" ceratopsian of the late Cretaceous period, the pig-sized Protoceratops.

How did Leptoceratops manage to be such a throwback to the distant progenitors of the ceratopsian family, tiny, dog-sized creatures like Psittacosaurus and Archaeoceratops that lived millions of years earlier? Clearly, the ecosystem of late Cretaceous North America had room for at least one genus of small ceratopsian, which presumably stayed well out of the way of its smaller cousins (and may even have done them a favor, by attracting the interest of hungry tyrannosaurs and raptors). Its low position on the food chain also explains another strange attribute of Leptoceratops, its ability to run away on its two hind legs when threatened!

Liaoceratops

Name:

Liaoceratops (Greek for "Liao horned face"); pronounced LEE-ow-SEH-rah-tops

Habitat:

Woodlands of Asia

Historical Period:

Early Cretaceous (130-125 million years ago)

Size and Weight:

About three feet long and 10-15 pounds

Diet:

Plants

Distinguishing Characteristics:

Small size; small frill on head; possible bipedal posture

Voluminous evidence has come forward of early Cretaceous and even late Jurassic ceratopsian precursors, a notable example of which is Liaoceratops. Like other "basal" ceratopsians such as Chaoyangsaurus and Psittacosaurus, Liaoceratops was a pint-sized herbivore with a tiny, almost unnoticeable frill, and unlike later ceratopsians, it may have walked on its two hind legs. Paleontologists are still sorting out the evolutionary relationships among these ancient dinosaurs; all we can say for certain is that the ceratopsians as a whole originated in Asia.

Magnirostris

Name:

Magnirostris (Latin for "large beak"); pronounced MAG-nih-ROSS-triss

Habitat:

Deserts of central Asia

Historical Period:

Late Cretaceous (75-70 million years ago)

Size and Weight:

About eight feet long and 400 pounds

Diet:

Plants

Distinguishing Characteristics:

Moderate size; large, sharp beak

Although it was described and named by the famous Chinese paleontologist Dong Zhiming, Magnirostris may or may not deserve its own genus. Most experts believe this dinosaur was actually a juvenile of a similar ceratopsian of late Cretaceous Mongolia, Bagaceratops, and it may even conceivably have been a species of Protoceratops. However this dinosaur winds up being classified, the skull of Magnirostris is one of the best-preserved in the (small) ceratopsian fossil record, with a sharp, horny, roughly triangular beak that must have come in handy for shearing off tough vegetation.

Medusaceratops

Name:

Medusaceratops (Greek for "Medusa horned face"); pronounced meh-DOO-sah-SEH-rah-tops

Habitat:

Woodlands of North America

Historical Period:

Late Cretaceous (80-75 million years ago)

Size and Weight:

About 20 feet long and 2 tons

Diet:

Plants

Distinguishing Characteristics:

Large head with elaborate frill; two horns on forehead

One of a group of ceratopsian dinosaurs announced in 2010, Medusaceratops looked like a cross between a Triceratops and a Centrosaurus. It had two Triceratops-sized horns jutting out of the top of its head, but also a large, flat, vaguely butterfly-shaped frill reminiscent of the latter dinosaur. The horns and frill were probably sexually selected characteristics, meaning males with bigger such accessories had the opportunity to mate with more females. Alternatively, the horns may also have been used for intra-pack tussling and the frill as a means of communication if it was capable of changing colors. The "Medusa" part of this dinosaur's name, after the ancient Greek monster with snakes instead of hair, refers to the strange, bony, snake-like growths around Medusaceratops' frill.

Mercuriceratops

Name

Mercuriceratops (Greek for "Mercury horned face"); pronounced mer-CURE-ih-SEH-rah-tops

Habitat

Plains of North America

Historical Period

Late Cretaceous (77 million years ago)

Size and Weight

About 15 feet long and 2-3 tons

Diet

Plants

Distinguishing Characteristics

Large frill with "wings" on bottom; two horns above eyes

What made Mercuriceratops stand out from the dozens of other ceratopsians of its habitat were the distinctive, wing-shaped protrusions on the bottom of its frill, which bear some resemblance to the helmet of the winged Greek god Mercury. Notably, almost identical specimens of this dinosaur were recently discovered on either side of the U.S./Canada border, straddling northern Montana and southern Alberta Province (hence this ceratopsian's species name, M. gemini).

Microceratops

The ancestral ceratopsian most people know as Microceratops received a name change in 2008, to the slightly less snazzy Microceratus, because it turned out that "Microceratops" had already been assigned to a genus of insect.

Mojoceratops

Name:

Mojoceratops (Greek for "mojo horned face"); pronounced moe-joe-SEH-rah-tops

Habitat:

Woodlands of North America

Historical Period:

Late Cretaceous (75 million years ago)

Size and Weight:

About 12 feet long and 1-2 tons

Diet:

Plants

Distinguishing Characteristics:

Large, heart-shaped frill on back of head

Fossil hunter Nicholas Longrich certainly had his mojo on when he diagnosed this new ceratopsian dinosaur based on a skull he found in storage at the American Museum of Natural History in New York (along with other partial skulls residing in Canadian museums).

Mojoceratops' claim to fame is that its frill was even more elaborate than that of its closest relative, Centrosaurus: a tall, wide, bone-supported sail of skin that probably changed color with the seasons. To judge by its underlying skeletal structure, Mojoceratops' frill was probably heart-shaped, which was fitting in that males used their frills to broadcast sexual availability (or desire) to the females of the herd.

Monoclonius

Today, many paleontologists believe that the identified fossil specimens of Monoclonius should be assigned to Centrosaurus, which had a strikingly similar head equipped with one big horn on the end of its snout.

Montanoceratops

Name

Montanoceratops (Greek for "Montana horned face"); pronounced mon-TAN-oh-SEH-rah-tops

Habitat

Woodlands of North America

Historical Period

Late Cretaceous (70 million years ago)

Size and Weight

About 10 feet long and 500 pounds

Diet

Plants

Distinguishing Characteristics

Small size; short frill and beak

The famous paleontologist Barnum Brown didn't know quite what to make of Montanoceratops when he unearthed its remains in Montana in 1916; it took him almost 20 years for him to get around to describing the type fossil, which he assigned to another basal ceratopsian, Leptoceratops. A few years later, another naturalist, Charles M. Sternberg, reexamined the bones and erected the new genus Montanoceratops. The important thing about Montanoceratops is that it was a relatively small, "primitive" ceratopsian that shared its habitat with more advanced forms like Centrosaurus and Styracosaurus. Clearly, these differently sized dinosaurs occupied different ecological niches, and did not directly compete with one another for food and other resources.

Nasutoceratops

Name:

Nasutoceratops (Greek for "big-nosed horned face"); pronounced nah-SOO-toe-SEH-rah-tops

Habitat:

Woodlands of North America

Historical Period:

Late Cretaceous (70-65 million years ago)

Size and Weight:

About 15 feet long and 1-2 tons

Diet:

Plants

Distinguishing Characteristics:

Large nose; forward-facing brow horns

Nasutoceratops, first identified in 2013, was distinguished from others of its kind by its unusually large nose and the remarkably steer-like pair of horns jutting out from over its eyes. On the other hand, the frill of Nasutoceratops was nothing special, lacking the elaborate notches, ridges, fringes, and decorations of other ceratopsians. As with other dinosaurs, Nasutoceratops likely evolved its facial characteristics as a means of intra-species recognition and sexual differentiation—(that is, males with bigger noses and straighter horns were more attractive to females.

Ojoceratops

Name:

Ojoceratops (Greek for "Ojo horned face"); pronounced OH-ho-SEH-rah-tops

Habitat:

Woodlands of southern North America

Historical Period:

Late Cretaceous (70 million years ago)

Size and Weight:

About 20 feet long and 2-3 tons

Diet:

Plants

Distinguishing Characteristics:

Two large horns over eyes; distinctive frill

This ceratopsian, the fossils of which were recently discovered in New Mexico's Ojo Alamo Formation, looked an awful lot like its more famous cousin Triceratops, though it did have a somewhat distinctive, roundish frill. Ojoceratops, however, seems to have lived a few million years before Triceratops, which is probably the only thing that will keep it in the official dinosaur record books.

Pachyrhinosaurus

Pachyrhinosaurus ("thick-nosed lizard") was a close relative of Triceratops that had an unusually thick nose, probably an evolutionary adaptation by which males could butt each other (without killing themselves) for the attention of females.

Pentaceratops

The name Pentaceratops ("five-horned face") is a bit of a misnomer: this ceratopsian actually had only three real horns, the other two being outgrowths of its cheekbones. Still, this dinosaur possessed one of the biggest heads (in relation to its size) of any animal that ever lived.

Prenoceratops

Name:

Prenoceratops (Greek for "bent horned face"); pronounced PRE-no-SEH-rah-tops

Habitat:

Woodlands of North America

Historical Period:

Late Cretaceous (85-75 million years ago)

Size and Weight:

About 4-5 feet long and 40-50 pounds

Diet:

Plants

Distinguishing Characteristics:

Small size; blunt head with minimal frill

You'd have to be a trained paleontologist to distinguish Prenoceratops from its more famous relative, Leptoceratops, which lived a few million years later. Both of these ceratopsians (horned, frilled dinosaurs) were small, slender, unobtrusive plant-eaters with minimal frills, a far cry from "classic" members of the breed like Triceratops and Pentaceratops. One among dozens of ceratopsian genera of the late Cretaceous period, Prenoceratops stands out from the pack in at least one way: its fossils were discovered in Montana's famous Two Medicine Formation.

Protoceratops

In late Cretaceous central Asia, the pig-sized Protoceratops seems to have filled roughly the same evolutionary niche as the modern wildebeest—a common, relatively easy-to-kill source of food for hungry carnivorous dinosaurs.

Psittacosaurus

You wouldn't know from looking at it, but Psittacosaurus (Greek for "parrot lizard") was an early member of the ceratopsian family. Numerous fossil specimens of this dinosaur have been discovered in eastern Asia, pointing to its gregarious, herding nature.

Regaliceratops

Name

Regaliceratops (Greek for "regal horned face"); pronounced REE-gah-lih-SEH-rah-tops

Habitat

Woodlands of North America

Historical Period

Late Cretaceous (70-65 million years ago)

Size and Weight

About 16 feet long and two tons

Diet

Plants

Distinguishing Characteristics

Large head with ornate, crown-shaped frill

Discovered in Canada's Alberta province in 2005, but only announced to the world in June of 2015, Regaliceratops had a huge frill unlike any other dinosaur of its breed—a round, upright, bizarrely crenelated structure. As with other ceratopsians, Regaliceratops doubtless evolved its frill as a sexually selected characteristic; it may also have helped with intra-herd recognition, considering how common thick horned, frilled dinosaurs were during the late Cretaceous in North America.

Rubeosaurus

However it winds up being classified, Rubeosaurus was a distinctive-looking ceratopsian of late Cretaceous North America, with its long nose horn and (especially) the two long, converging spikes set atop its voluminous frill. See an in-depth profile of Rubeosaurus

Sinoceratops

Name

Sinoceratops (Greek for "Chinese horned face"); pronounced SIE-no-SEH-rah-tops

Habitat

Woodlands of eastern Asia

Historical Period

Late Cretaceous (70-65 million years ago)

Size and Weight

About 12 feet long and 1-2 tons

Diet

Plants

Distinguishing Characteristics

Single nose horn; short, decorated frill

As a general rule, the dinosaurs of late Cretaceous North America, especially hadrosaurs and tyrannosaurs, had (often larger) counterparts in eastern Asia. A curious exception to this rule is the ceratopsians (horned, frilled dinosaurs), which have yielded extensive fossil remains in North America but virtually nothing in China dating to the last half of the Cretaceous period. That's why the announcement of Sinoceratops in 2010 was such big news: for the first time, paleontologists had unearthed a full-sized, late Cretaceous, Asian ceratopsian that could have given Triceratops a run for its money. A "centrosaurine" ceratopsian, so characterized because of its short frill, Sinoceratops was endowed with a single nasal horn, and its frill was decorated with various knobs and "hornlets." The prevailing theory is that this dinosaur (or more likely one of its ancestors) crossed the Bering land bridge from Alaska to Siberia; perhaps, if the K/T Extinction hadn't intervened, Asia might have fully replenished its stock of ceratopsians.

Spinops

The fragmented bones of Spinops were interred for nearly 100 years before a team of paleontologists finally got around to examining them; the "type fossil" of this dinosaur was discovered in 1916, in Canada, by the famous paleontologist Charles Sternberg. See an in-depth profile of Spinops

Styracosaurus

Styracosaurus had the most rococo, gothic-looking head of any ceratopsian, an imposing potpourri of spikes, horns, frills, and unusually large nostrils. Most likely, Styracosaurus males with more elaborate frills were more attractive to the females of the genus.

Tatankaceratops

Name

Tatankaceratops (Greek for "buffalo horned face"); pronounced tah-TANK-ah-SEH-rah-tops

Habitat

Woodlands of North America

Historical Period

Late Cretaceous (65 million years ago)

Size and Weight

Undisclosed

Diet

Plants

Distinguishing Characteristics

Moderate size; quadrupedal posture; horns and frill

Not to be confused with Tatankacephalus—an armored dinosaur, also named after the modern buffalo, that lived tens of millions of years earlier—Tatankaceratops was diagnosed on the basis of a single, partial skull discovered in South Dakota. However, not everyone agrees that this late Cretaceous ceratopsian deserves its own genus. The more likely scenario is that the type specimen of Tatankacephalus was a young Triceratops with a birth defect that caused it to stop growing since the fossil presents an odd mixture of adult and juvenile traits (especially as pertains to its horns and frill).

Titanoceratops

Name:

Titanoceratops (Greek for "titanic horned face"); pronounced tie-TAN-oh-SEH-rah-tops

Habitat:

Woodlands of North America

Historical Period:

Late Cretaceous (75 million years ago)

Size and Weight:

Up to 25 feet long and five tons

Diet:

Plants

Distinguishing Characteristics:

Large size; ornate frill and horns

After examining an unusually large Pentaceratops noggin on display at the Oklahoma Museum of Natural History, Yale's Nicholas Longrich determined that this fossil should actually be attributed to a brand-new ceratopsian genus, Titanoceratops. This isn't merely a matter of Titanoceratops being slightly different from Pentaceratops; what Longrich is claiming is that his new dinosaur was actually more closely related to Triceratops, and was one of the earliest "triceratopsine" ceratopsians. This would mean that the genus dates to 75 million years ago, about 5 million years before better-known ceratopsians in this family like Triceratops, Chasmosaurus, and Centrosaurus.

Assuming its genus classification is widely accepted, the appropriately named Titanoceratops would have been one of the largest ceratopsians, potentially reaching lengths of 25 feet from head to tail and weights in the neighborhood of five tons.

Torosaurus

Name:

Torosaurus (Greek for "pierced lizard"); pronounced TORE-oh-SORE-us

Habitat:

Woodlands of western North America

Historical Period:

Late Cretaceous (70 million years ago)

Size and Weight:

About 25 feet long and four tons

Diet:

Plants

Distinguishing Characteristics:

Enormous frill; two long horns over eyes

From its name, you might think Torosaurus was named after a bull ("toro" in Spanish), but the truth is a bit less exciting. The "toro" in this case means "perforated" or "pierced," referring to the large holes in this herbivore's skull, beneath its enormous frill.

Names aside, Torosaurus was a typical ceratopsian—a member of the family of horned, frilled, elephant-sized dinosaurs that populated the North American continent during the late Cretaceous period, the most famous examples of which were Triceratops and Centrosaurus. In fact, according to a recent study, Torosaurus may well have been the same dinosaur as Triceratops, since the frills of ceratopsians continued to grow as they aged.

Triceratops

Triceratops had one of the most unmistakable skulls of any creature that ever lived. This may explain be why Triceratops fossils are especially valuable at auction, near-complete specimens commanding prices in the millions of dollars.

Udanoceratops

Name:

Udanoceratops (Greek for "Udan horned face"); pronounced OO-dan-oh-SEH-rah-tops

Habitat:

Deserts of central Asia

Historical Period:

Late Cretaceous (80-75 million years ago)

Size and Weight:

About 13 feet long and 1,500 pounds

Diet:

Plants

Distinguishing Characteristics:

Blunt head with horned beak; possible bipedal posture

Anatomically, this dinosaur shared some characteristics with the much smaller, "basal" ceratopsians that preceded it by millions of years (the most notable example being Psittacosaurus), but it was much bigger than these early plant-eaters, full-grown adults possibly weighing as much as a ton. Even more tantalizingly, the fact that basal ceratopsians were mostly bipedal hints that Udanoceratops may also have spent most of its time on two legs, which would make it by far the largest such ceratopsian.

Unescoceratops

Name:

Unescoceratops (Greek for "UNESCO horned face"); pronounced you-NESS-coe-SEH-rah-tops

Habitat:

Woodlands of North America

Historical Period:

Late Cretaceous (75 million years ago)

Size and Weight:

About five feet long and 200 pounds

Diet:

Plants

Distinguishing Characteristics:

Small size; short frill; tough, horny beak

The newly discovered Unescoceratops wasn't the smallest ceratopsian (horned, frilled dinosaur) that ever lived—that honor belongs to "basal" species like Leptoceratops—but it still didn't have much to brag about. About five feet long from head to tail, Unescoceratops only weighed about as much as a healthy, adult human, and it possessed a short frill and a tough, horny beak reminiscent of a parrot's. The most notable thing about this dinosaur is its name: it was discovered near Canada's Dinosaur Provincial Park, a World Heritage site administered by UNESCO (The United Nations Educational, Scientific and Cultural Organization).

Utahceratops

Name:

Utahceratops (Greek for "Utah horned face"); pronounced YOU-tah-SEH-rah-tops

Habitat:

Woodlands of North America

Historical Period:

Late Cretaceous (75-65 million years ago)

Size and Weight:

About 20 feet long and 3-4 tons

Diet:

Plants

Distinguishing Characteristics:

Rhino-like horn on snout; large head and frill

During the late Cretaceous period, from about 75 to 65 million years ago, the shallow Western Interior Sea carved out an "island continent" in the vicinity of modern-day Utah, which is where the remains of Utahceratops were recently unearthed. This herbivore had a single, rhino-like horn projecting from the top of its snout, as well as a pair of steer-like horns jutting out sideways from the top of its eyes. Most alarmingly, the skull of Utahceratops was huge—about seven feet long—which has prompted one paleontologist to describe this dinosaur as "a giant rhino with a ridiculously supersized head."

The island habitat of Utahceratops may have had something to do with the development of the animal's complex horn and frill structure. As with most such dinosaur appurtenances, it's clear that the oversized horns and frill of this dinosaur were meant to impress the opposite sex and help to propagate the species.

Vagaceratops

Name

Vagaceratops (Greek for "wandering horned face"); pronounced VAY-gah-SEH-rah-tops

Habitat

Woodlands of western North America

Historical Period

Late Cretaceous (75-70 million years ago)

Size and Weight

About 15 feet long and 1-2 tons

Diet

Plants

Distinguishing Characteristics

Large, broad frill; short nasal horn

More ceratopsians have been discovered in Utah than any other type of dinosaur, especially over the last five years. One recent addition to the roster is Vagaceratops, which occupies a place very close to Kosmoceratops on the ceratopsian family tree (both of these "centrosaurine" ceratopsians were themselves closely related to Centrosaurus). Vagaceratops was characterized by its short nasal horn and broad, flat, relatively unadorned frill, which is somewhat odd since Kosmoceratops possessed the most ornate frill of any identified ceratopsian. Reconstructions of Vagaceratops have also been used in simulations of ceratopsian posture, as experts try to figure out whether these dinosaurs' legs were slightly splayed (like those of lizards) or more "locked in" and upright.

Wendiceratops

Name

Wendiceratops (Greek for "Wendy's horned face"); pronounced WEN-dee-SEH-rah-tops

Habitat

Woodlands of North America

Historical Period

Late Cretaceous (80 million years ago)

Size and Weight

About 20 feet long and one ton

Diet

Plants

Distinguishing Characteristics

Ornate frill; horn on snout

Announced to the world in 2015, the horned, frilled dinosaur Wendiceratops is important for three reasons. First, it's the earliest identified ceratopsian dinosaur to sport a horn on its nose; second, it's one of the earliest identified members of the family of ceratopsians that eventually gave rise to Triceratops about 10 million years later; and third, the elaborate ornamentation of its head and frill show that these striking anatomical features evolved millions of years before paleontologists had previously thought. Wendiceratops is also one of the handful of dinosaurs to be named after a female, in this case noted Canadian fossil hunter Wendy Sloboda, who discovered its bonebed in Alberta in 2010.

Xenoceratops

Name:

Xenoceratops (Greek for "alien horned face"); pronounced ZEE-no-SEH-rah-tops

Historical Period:

Late Cretaceous (80 million years ago)

Habitat:

Woodlands of North America

Size and weight:

About 20 feet long and three tons

Diet:

Plants

Distinguishing Characteristics:

Large, two-horned frill; long brow horns

Over the past decade, more ceratopsians (horned, frilled dinosaurs) have been identified than any other type of dinosaur, probably because these plant-eaters' massive skulls tend to persist well in the fossil record. In November of 2012, paleontologists announced yet another ceratopsian genus, Xenoceratops, the fossils of which were discovered in 80-million-year-old sediments in the Belly River Formation of Alberta, Canada.

As is the case with many other dinosaurs, the naming of Xenoceratops came well after its original discovery. The scattered remains of this ceratopsian were actually unearthed way back in 1958 and then consigned to a dusty museum drawer for over half a century. It was only recently that paleontologists from the Royal Ontario Museum reexamined the fossils and determined that they were dealing with a new genus and not an existing ceratopsian species.

This ceratopsian predated more famous relatives like Styracosaurus and Centrosaurus by a few million years (late Cretaceous ceratopsians are relatively common, but most date back 70 to 65 million years, not 80 million years). Oddly enough, though, Xenoceratops already possessed a fairly elaborate, horn-studded frill, an indication that ceratopsians developed these distinctive features earlier than was once thought.

Xuanhuaceratops

Name:

Xuanhaceratops (Greek for "Xuanhua horned face"); pronounced ZHWAN-ha-SEH-rah-tops

Habitat:

Woodlands of Asia

Historical Period:

Late Jurassic (160-150 million years ago)

Size and Weight:

About three feet long and 10-15 pounds

Diet:

Plants

Distinguishing Characteristics:

Small size; beaked snout; bipedal posture

Xuanhuaceratops was one of the earliest ceratopsians, the line of herbivorous dinosaurs that evolved from ornithopods during the late Jurassic period and culminated in giant North American genera like Triceratops and Pentaceratops during the late Cretaceous, tens of millions of years later. Xuanhuaceratops was closely related to another early ceratopsian, Chaoyangsaurus, which may have predated it by a few million years (and thus may have been its direct ancestor).

Yamaceratops

Name:

Yamaceratops (Greek for "Yama horned face"); pronounced YAM-ah-SER-ah-tops

Habitat:

Woodlands of Asia

Historical Period:

Middle Cretaceous (100 million years ago)

Size and Weight:

About six feet long and 50-100 pounds

Diet:

Plants

Distinguishing Characteristics:

Small size; short frill

Although it's a fairly obscure dinosaur, Yamaceratops (it was named after the Buddhist deity Yama) is important for two reasons. First, this ceratopsian—a member of the same family that later gave rise to Triceratops and Centrosaurus—lived in Asia, whereas later ceratopsians were confined to North America. And second, Yamaceratops prospered tens of millions of years before its more famous descendants, during the middle rather than the late Cretaceous period. Considering its early place on the ceratopsian evolutionary tree, it's easy to understand Yamaceratops' unusually short, primitive frill (compared to the huge, elaborate productions of later dinosaurs like Chasmosaurus), not to mention its relatively small size, only about 100 pounds.

Yinlong

Name:

Yinlong (Chinese for "hidden dragon"); pronounced YIN-long

Habitat:

Woodlands of Asia

Historical Period:

Late Jurassic (160-155 million years ago)

Size and Weight:

About four feet long and 20 pounds

Diet:

Plants

Distinguishing Characteristics:

Small size; relatively broad head

The name Yinlong ("hidden dragon") is something of an inside joke: the fossils of this dinosaur were found in the part of China where the epic movie Crouching Tiger, Hidden Dragon was filmed. Yinlong's claim to fame is that it's the oldest ceratopsian dinosaur yet identified, a tiny, late Jurassic precursor of much bigger horned dinosaurs of the late Cretaceous period like Triceratops and Centrosaurus. Tantalizingly, the fossils of Yinlong bear some resemblance to those of Heterodontosaurus, a clue that the first ceratopsians evolved from equally small ornithopods about 160 million years ago. (By the way, Yinlong was portrayed in a National Geographic special as prey for the tiny tyrannosaur Guanlong, though direct evidence for this is lacking.)

Zhuchengceratops

Name

Zhuchengceratops (Greek for "Zhucheng horned face"); pronounced ZHOO-cheng-SEH-rah-tops

Habitat

Woodlands of Asia

Historical Period

Late Cretaceous (75 million years ago)

Size and Weight

About seven feet long and 500 pounds

Diet

Plants

Distinguishing Characteristics

Small size; strong muscles in lower jaw

A close relative of the roughly contemporary Leptoceratops -with which it's technically grouped as a "leptoceratopsian," Zhuchengceratops was a modestly scaled herbivore characterized by its unusually muscular jaws (a hint that it subsisted on particularly tough vegetation.) Whereas the North American Leptoceratops coexisted with the larger, more familiar ceratopsians of its day, like Triceratops, Zhuchengceratops and its pig-sized ilk were the only horned, frilled dinosaurs of late Cretaceous Asia. (Ceratopsians arose in eastern Eurasia in the early Cretaceous period, but only evolved to massive sizes once they had reached North America.) As might be supposed from their names, Zhuchengceratops probably figured on the lunch menu of the contemporary theropod Zhuchengtyrannus.

Zuniceratops

Name:

Zuniceratops (Greek for "Zuni horned face"); pronounced ZOO-nee-SER-ah-tops

Habitat:

Woodlands of western North America

Historical Period:

Late Cretaceous (90 million years ago)

Size and Weight:

About 10 feet long and 200-300 pounds

Diet:

Plants

Distinguishing Characteristics:

Small size; medium-sized frill; short horns over eyes

When eight-year-old Christopher James Wolfe (the son of a paleontologist) happened upon the bones of Zuniceratops in New Mexico in 1996, the discovery was noteworthy for more than just Christopher's age. Subsequent dating of its fossil showed that Zuniceratops lived 10 million years before the bigger ceratopsians of the late Cretaceous period, such as Triceratops and Styracosaurus—making it the earliest known ceratopsian in North America.

Zuniceratops certainly looked like the predecessor of the mighty ceratopsians named above. This herbivore was very small, weighing only about 200 pounds, and its short frill and stunted double horns over its eyes have a distinctly half-evolved appearance. Clearly, later ceratopsians followed this same basic body plan, but elaborated on the details.