Species: Stokesosaurus clevelandi (Stoke-so-sore-us kleev-land-eye)
Tanycolagreus topwilsoni (Ta-nee-koe-la-grr-eh-us top-will-son-eye)
What it means: Stokesosaurus = Stokes’ lizard
Tanycolagreus = Long-limbed hunter
Other Species: None
Where I live: Western U.S.A.- The Morrison Formation
When to find me: The Late Jurassic period, about 152 million years ago.
My favorite food: Meat! We’re carnivores.
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 and smaller friends who sometimes join us for lunch…
- Long-necked sauropods like Apatosaurus, Brachiosaurus, Camarasaurus, Diplodocus, Barosaurus, Suuwassea, Supersaurus, Haplocanthosaurus, and Dystrophaeus.
- Armored dinosaurs like Stegosaurus, Hesperosaurus, Mymoorapelta, and Gargoyleosaurus.
- Two-legged ornithopods like Dryosaurus, Camptosaurus, and Nanosaurus
Fellow predators in the neighborhood include dinosaurs like Allosaurus, Torvosaurus, Ceratosaurus, Saurophaganax, Marshosaurus, Ornitholestes, Coelurus, Elaphrosaurus, and Koparion.
Plus there are all the small snacks scurrying around…countless lizards, crocodile relatives on land and water, mammals, frogs, turtles, fish. Pterosaurs fly in the sky after bugs.
- Stokesosaurus is named after Utah geologist William Lee Stokes, who excavated thousands of Allosaurus bones with his assistant James H. Madsen. When Madsen catalogued these bones in the early 1970s, he discovered that some of the remains were of species new to science. He named it Sokesosaurus. The town of Cleveland, Utah gives the animal its species name.
- Tanycolagreus is named so because its arms are longer than those of Coelurus, a similar animal from the same formation. It is from the Greek- tany (long/stretched out) + kolon (limb. Not to be confused with colon) + agreus (hunter. The r has a slight roll to it) = long-limbed hunter. The species name honors George Eugene “Top” Wilson, retired, United States Marine Corps.
- It’s been suggested that Tanycolagreus and Stokesosaurus are synonymous. They are of similar estimated size, come from the same time and place, and all fossils known for Tanycolagreus are indistinguishable from fragmentary remains attributed to Stokesosaurus. Stokesosaurus only has a single hip bone confirmed to be identifiable from that genus, and Tanycolagreus does not have any fossil ilium preserved thus far, so it is impossible to know for sure. It’s a classic case of “we need more fossils.”
- If more complete remains of Stokesosaurus of Tanycolagreus are discovered and confirm they are the same genus, then the older name of Stokesosaurus will be used.
Stokesosaurus- A single left ilium, or hip bone, from a young individual. Other fragmentary remains have been assigned to Stokesosaurus, but not confirmed.
Tanycolagreus- Fragmentary and/or partial remains of several individuals. These fossils preserved most of the post-cranial bones (anything behind the head), but two preserve some fragmentary remains of the skull. No ilium preserved thus far, which causes controversy concerning Stokesosaurus.
Foster, John. Jurassic West: The Dinosaurs of the Morrison Formation and Their World. Indiana University Press, 2007
Carpenter, Kenneth & Miles, C. & Cloward, K.. (2005). New small theropod from the Upper Jurassic Morrison Formation of Wyoming. The Carnivorous Dinosaurs. 23-48. https://www.researchgate.net/publication/313050250_New_small_theropod_from_the_Upper_Jurassic_Morrison_Formation_of_Wyoming
“Stokesosaurus.” Wikipedia, https://en.wikipedia.org/wiki/Stokesosaurus
“Tanycolagreus.” Wikipedia, https://en.wikipedia.org/wiki/Tanycolagreus