Named By: C. M. Brown, D. C. Evans, M. J. Ryan, A. P. Russel - 2013.
Classification: Chordata, Reptilia, Dinosauria, Ornithischia, Ornithopoda, Thescelosauridae, Orodrominae.
Species: A. syntarsus (type).
Size: Roughly estimated about 1.5-1.6 meters long.
Known locations: Canada, Alberta - Oldman Formation.
Time period: Campanian of the Cretaceous.
Fossil representation: Incomplete post cranial remains including left tibia and fibula, right fibula, fragmentary metatarsal and ungual, caudal (tail) vertebrae and two dorsal (back) vertebrae, cervical ribs, and ossified tendons.
only described from very incomplete remains, the relatively good
state of preservation of them has allowed for the description of a new
genus, Albertadromeus. Albertadromeus
is believed to have been a
small cursorial (ground dwelling) ornithopod that roamed around on
just its two rear legs. The preserved limb elements known show that
the distal ends of the tibia and fibula (the lower leg bones) of
Albertadromeus were fused. This is the inspiration
for the type
species name ‘syntarsus’. At the time of its
Albertadromeus has been considered to be closely
related to the
The description Albertadromeus has also been used to support the increasingly popular idea that small dinosaurs like Albertadromeus were far more common in the late Cretaceous that previously thought. The simple reasoning is that smaller animals have smaller and more delicate bones which are less likely to survive the ravages of environmental conditions and the mouths of hungry carnivores. Also in 2013 another small dinosaur discovery, the early pachycephalosaur Acrotholus, was used to support this theory.
The Albertadromeus holotype remains were discovered in the Oldman formation of Canada, indicating that Albertadromeus may have spent its time foraging amongst other herbivores such as the hadrosaurs Parasaurolophus and Corythosaurus, and ceratopsians such as Chasmosaurus and Albertaceratops. Danger however would come from small dromaeosaurs and troodonts such as Saurornitholestes, Troodon and Hesperonychus. Bigger threats would have been tyrannosaurs such as Daspletosaurus, and while a large adult would have likely had a very difficult time catching a small and nimble dinosaur like Albertadromeus, younger juvenile tyrannosaurs are noted for their potential speed. It may be that juvenile Daspletosaurus hunted small dinosaurs like Albertadromeus before graduating to larger hadrosaurs and ceratopsians in later adult life.
- New data on the diversity and abundance of small-bodied ornithopods (Dinosauria, Ornithischia) from the Belly River Group (Campanian) of Alberta, C. M. Brown, D. C. Evans, M. J. Ryan, A. P. Russel - 2013.