Species: Glyptops plicatulus (glip-tops plee-cat-you-lus)
What it means: Grooved face
Other Species: G. utahensis?
Where I live: Western U.S.A.- The Morrison Formation
When to find me: The Late Jurassic period, about 155 million years ago.
My favorite food: All sorts of grubs, fish, snails, and plants! I’m an omnivore.
My neighborhood: The Morrison Formation covers a huge expanse of land with a variety of different habitats teaming with life. Most of it was very much like the Serengeti of modern day Africa, only with prairies of drought-tolerant ferns and cycad relatives instead of grass. Dense woodlands of tall conifers like the modern araucaria, ginkgoes, and tree ferns would only lie in places of plentiful water such as the few permanent rivers. Other areas had far more sparse and shrubbier vegetation like the open woodlands of acacia trees in the Serengetti.
Life in this environment would’ve adapted to long months of harsh drought, followed by a few months of monsoon that flooded the rivers. Many of the larger herbivores may have migrated like the herds in Africa do today, while most carnivores stayed behind to feast on the dead and dying, or else become opportunistic hunters of less traditional diets for lean times, such as fish or turtles in the rivers.
A few of my neighbors: First let me share the plant-eating giants…
- Long-necked sauropods like Brachiosaurus, Camarasaurus, Diplodocus, Barosaurus, Apatosaurus, Suuwassea, Supersaurus, Haplocanthosaurus, and Dystrophaeus.
- Armored dinosaurs like Stegosaurus, Hesperosaurus, Mymoorapelta, and Gargoyleosaurus.
- Two-legged ornithopods like Dryosaurus, Camptosaurus, and Nanosaurus
There are also giant, meat-eating monsters to worry about, including dinosaurs like Allosaurus, Torvosaurus, Ceratosaurus, Saurophaganax, Marshosaurus, Stokesosaurus, Ornitholestes, Coelurus, Tanycolagreus, Elaphrosaurus, and Koparion.
Not to mention the countless lizards, crocodile relatives on land and water, mammals, frogs, turtles, fish, and all the pterosaurs flying in the sky!
- A partial skull of Glyptops was originally named by famous paleontologist Othniel Charles Marsh, who named the fossils Glyptops ornatus. The type species, and the fossils upon which all other Glyptops fossils are compared with, was described by his equally famous rival, Edward Drinker Cope, who found a partial shell around the same time and named it Compsemys plicatulus. The fossils were later determined to be the same animal, and so the names were combined into Glyptops plicatulus.
- Glyptops is a type of turtle known as a cryptodire, or arch-necked turtle. They fold their necks vertically to tuck their heads inside their shell like modern box turtles and tortoises. Side-necked turtles fold the neck sideways to tuck their heads under the rim of their shells.
- Glyptops turtles have ridges on the surface of the shell that makes them easy to tell apart from the other three turtles of the Morrison Formation. The ridges are more pronounced in juveniles.
- The shells of these turtles can grow to about a foot long, or about 30 centimeters.
Fossil Finds: One or two nearly complete skulls, and one or two complete and nearly complete shells from adults and juveniles. Plus lots, and lots, and lots of shell pieces. This turtle was everywhere, and was by far the most common.
“Glyptops plicatulus.” National Park Service, https://www.nps.gov/dino/learn/nature/glyptops-plicatulus.htm
JAMES M. CLARK, A new shartegosuchid crocodyliform from the Upper Jurassic Morrison Formation of western Colorado, Zoological Journal of the Linnean Society, Volume 163, Issue suppl_1, December 2011, Pages S152–S172, https://doi.org/10.1111/j.1096-3642.2011.00719.x
Foster, John. Jurassic West: The Dinosaurs of the Morrison Formation and Their World. Indiana University Press, 2007
“Glyptops.” Wikipedia, https://en.wikipedia.org/wiki/Glyptops
Foster, J.R. and Lucas, S.G., eds., 2006, Paleontology and Geology of the Upper Jurassic Morrison Formation: Glyptops (testudines, pleurosternidae)from the upper Jurassic Morrison formation, New Mexico. New Mexico Museum of Natural History and Science Bulletin 36. https://libres.uncg.edu/ir/asu/f/Heckert_A_2006_36_Glyptops.pdf