Gargoyleosaurus
From Wikipedia, the free encyclopedia
| iGargoyleosaurus | ||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
 |
||||||||||||||||||||||
|
|
||||||||||||||||||||||
|
Extinct (fossil)
|
||||||||||||||||||||||
| Scientific classification | ||||||||||||||||||||||
|
||||||||||||||||||||||
|
|
||||||||||||||||||||||
| Gargoyleosaurus parkpinorum Carpenter et al., 1998 |
Contents |
[edit] Overview
Gargoyleosaurus parkpinorum is both the smallest and earliest known ankylosaur. It was discovered at the Bone Cabin Quarry West locality, in Albany County, Wyoming, in exposures of the Upper Jurassic (Kimmeridgian-Tithonian) Morrison Formation. Its skull measures only 29 cm. in length, and the total body length of Gargoyleosaurus ("gargoyle lizard") is estimated to have been between three and four meters. It may have weighed as much as a ton. Much of the skull and skeleton has been recovered, and the taxon displays cranial sculpturing, including pronounced deltoid quadratojugal and squamosal bosses. The taxon is further characterized by a narrow rostrum (in dorsal view), the presence of seven conical teeth in each premaxilla, an incomplete osseous nasal septum, a linerarly arranged nasal cavity, the absence of an osseus secondary palate, and, as regards osteoderms, two sets of co-ossified cervical plates and a number of elongate conical spines. The next earliest known ankylosaur is Minmi paravertebrata from the Aptian of Queensland, Australia. A mounted skeletal reconstruction of Gargoyleosaurus parkpinorum can be seen at the Denver Museum of Natural History.
[edit] Holotype
The holotype specimen of Gargoyleosaurus parkpinorum was collected by Western Paleontology Labs in 1996 and is currently held in the collections of the Denver Museum of Natural History, Denver, Colorado. Only the holotype is known and consists of most of the skull and a partial postcranial skeleton. The specimen was originally described as Gargoyleosaurus parkpini by Carpenter et. al. (1998), then renamed G. parkpinorum by Carpenter et. al. 2001, in accordance with ICZN art. 31.1.2A.
[edit] Phylogenetics
Vickaryous et. al. (2004) place Gargoyleosaurus parkpinorum within the Family Ankylosauridae of the Ankylosauria and are in agreement with most previous phylogenetic hypotheses, which place the genus as the sister group to all other ankylosaurids (i.e., members of the Ankylosauridae).
[edit] References
- Carpenter, K., Miles, C. and Cloward, K.. 1998. Skull of a Jurassic ankylosaur (Dinosauria). Nature 393: 782-783.
- Carpenter, K. (ed.) The Armored Dinosaurs. pp. 454-483. Indiana University Press, Bloomington.
- Vickaryous, Maryanska, and Weishampel 2004. Chapter Seventeen: Ankylosauria. in The Dinosauria (2nd edition), Weishampel, D. B., Dodson, P., and Osmólska, H., editors. University of California Press.
