Species That Don't Get Enough Publicity #5: Anchiceratops

Triceratops is my favorite dinosaur. I don’t know why. Maybe it’s because it’s both a plant eater and intimidating. Maybe because it’s like a rhino or a bull. Maybe because it can stand up and defeat the greatest monster dinosaur in media.  It’s been my favorite dinosaur for a while, actually, although I’ve grown to know and love the rest of the horned dinosaurs.  Triceratops is by far the best known, but others have appeared in media.  The sister species Torosaurus managed to get a supporting role in Walking With Dinosaurs, while the spiky-frilled Styracosaurus has become second to only Triceratops in popularity due to its unique look and made its film debut in the 1933 Kong movies (albeit the scene was cut from the first).  Pachyrhinosaurus has surprisingly been popular-being a background dinosaur with Styracosaurus in Disney’s Dinosaur, playing a supporting role in documentaries like The Dinosaurs, March of the Dinosaurs, and Jurassic Fight Club, and finally being the star of the movie Walking With Dinosaurs. 

There’s several that have slipped under the radar, but are well known from science books and dinosaur encyclopedias, but have made occasional appearances. Chasmosaurus (or should I say Mojoceratops) was the only dinosaur in When Dinosaurs Ruled the Earth. Centrosaurus has appeared in the documentary Dinosaur!, the short Prehistoric Beast, and has been popular in dinosaur art (sometimes as Monoclonius). A lot of the most recent ceratopsians such as Xenoceratops, Diabloceratops, Medusaceratops and so forth are too new to become engrained in media and culture. 

However, one dinosaur has really had a short shrift, and poor Anchiceratops deserves its due.

Anchiceratops was discovered by Barnum Brown, the same American Museum scientist who discovered Tyrannosaurus and Ankylosaurus. The specimen, parts of a skull, are now at American museum.  Charles Sternberg, the great Canadian paleontologist, found a headless body and a bodiless skull, and so mounted them together in the Canadian Museum of Nature.  The Royal Tyrell Museum and University of Michigan Museum have complete skulls, and the Field Museum and Royal Ontario museums have frill fragments. It’s actually better known that most ceratopsians along with  Styracosaurus, Centrosaurus, Chasmosaurus, (along with Vagaceratops and Mojoceratops), Torosaurus, Pentaceratops, and Triceratops.  However, it’s still rarer than most of the other animals in the fauna.

 Anchiceratops has only been found in appreciable quantities in the Horseshoe Canyon Formation, 72 million year old Canadian rock.  Other unique species include the ankylosaur Andontosaurus, the alvarezsaur Albertonykus, the dromeosaur Atrociraptor, the even rarer ceratopsians odd Arrhinoceratops and giant Eotriceratops, the small ornithopod Parksosaurus, the big hadrosaur Saurolophus, and the tyrannosaur Albertosaurus.  These species have only appeared in fragmentary form at best in other formations, but are well-represented here.  The environment appears to be a temperate swamp not unlike Louisiana today. W.J. Langston and Jordon Mallon have both argued that the long snout and stout build was an adaptation for amphibious habits, and that it is better represented at the Horseshoe Canyon because of the swampy environment that the animal would have preferred.   This theory is supported by Anchiceratops being rare in other contemporary formations, like the floodplains of the Oldman Formation and the poorly preserved St. Mary River Formation. There is a similar, unnamed genus at the Dinosaur Park and Almond formations that only recently has been considered distinct from Anchiceratops.  

The fact that the species, along with Albertosaurus and Saurolophus, has been restricted to the formation may explain their extinction. At around 70 million years ago, the recession of the Western Interior Seaway dried the adjoining deltas and river systems, eliminating the habitat. So Eotriceratops, Anchiceratops, Albertosaurus, and Saurolophus were replaced by the new, gigantic upland genera  Triceratops, Torosaurus, Tyrannosaurus, and Albertosaurus respectively.  Faunal turnover is a fascination of mine, and it’s interesting to speculate on how and why it occurred in the fossil record.

The animal was medium-sized as ceratopsians went-about 16 feet according to the Ottawa specimen, but if I was a lightly-built Albertosaurus, I’d still approach with caution.  The distinguishing features are the long snout, a pair of forward-facing epoccipitals (the triangular ornamental spikes on the frills of all ceratopsians), small parietal fenestrae (holes in the frills of all ceratopsians but Triceratops), square frill, short tail, and long neck. 

 Art by DinoHunter000 from DeviantArt

I think it’s this rarity that keeps it obscure.  Albertosaurus is also unique to the formation, but has been fleshed out by a dozen incomplete individuals of various ages as well as the close relative Gorgosaurus.  Another obscurity is simply because it didn’t live in the climactic days of the Maastrichtian age-Torosaurus and Ankylosaurus are similarly uncommon, but share the sites with the well-represented and famous Edmontosaurus, Tyrannosaurus and Triceratops.  It’s just bad luck, and as a luckless underdog, I can easily relate.  Here’s hoping we find more of Anchiceratops (along with the Dinosaur Park and Almond formation ceratopsian that may or may not be the same genus).

So anyway, Hollywood, give this guy a break. Museums, keep him on display. Toy companies, here’s a new fresh face. Authors, think about the crap you’re writing and how this genus could perk up the place. And remember, shop Anchiceratops where you work or play.

For another brief overview, here’s a post from the far superior Tetrapod Zoology blog by the incomparable Darren Naish http://scienceblogs.com/tetrapodzoology/2009/04/20/anchiceratops/