Pristichampsus

Taxobox
name = "Pristichampsus"
fossil_range = Paleocene to Eocene
regnum = Animalia
phylum = Chordata
classis = Sauropsida
ordo = Crocodilia
subordo = Eusuchia
familia = Pristichampsidae
genus = "Pristichampsus"
genus_authority = Gervais, 1853
subdivision_ranks = Species
subdivision =
*"P. rollinatii" (Gray, 1831)
*"P. vorax" (Troxell, 1925)
*"P. hengdongensis" (Li 1984)

"Pristichampsus" ("saw crocodile") is an extinct genus of crocodylian that grew to approximately three metres (10 ft) in length.

"Pristichampsus" was heavily armoured, with long limbs indicating a cursorial (i.e. running) lifestyle. Its toes had hoof-like unguls on them. Paleontologists hypothesise that it hunted terrestrial mammals. "Pristichampsus"'s teeth were laterally compressed, sharp and had serrated edges. Due to their similarity to those of certain theropod dinosaurs they were initially mistaken for theropod teeth, leading paleontologists to believe that some dinosaurs survived the Cretaceous-Tertiary extinction event.Fact|date=January 2008

Several remains of "Pristichampsus" have been found around the world: "P. rollinatii", the type species from the Lutetian of France; "P. vorax" from the Middle Eocene of Wyoming and West Texas; "P. hengdongensis" from the Paleocene of the Hengdon Basin in China, "P. birjukovi" and "P. kuznetzovi" from the Middle Eocene of Eastern Kazakhstan; "P. geiseltalensis" and "P. magnifrons" from the Lutetian of Germany.

Terristrial adaptations

The species, "P. rollinatii" displays the range of morphological adaptations to terrestrial carnivory made by this genus.Rossmann T. 2000. Studies on Cenozoic crocodiles: 5. Biomechanical investigation on the postcranial skeleton of the Palaeogene crocodile "Pristichampsus rollinatii" (Eusuchia: Pristichampsidae). "Neues Jahbuch fuer Geologie und Paläontologie Abh." 217 (3) 289-300.] It had extensive armour (osteoderms), and would have been an unlike swimmer, while the tail was more reminiscint of a dinosaur's, being round in cross-section and lacking the osteoderm crest observed in extant species. It also had relativey long limbs with the hoof-like unguals, and was capable of galloping and facultative bipedalism. However, this would only have been possible at high speeds as the centre of gravity moves in front of the pelvis.

References