Giraffatitan

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iGiraffatitan Fossil range: Late Jurassic
Giraffatitan brancai
Conservation status
Extinct (fossil)
Scientific classification
Kingdom: Animalia Phylum: Chordata Class: Sauropsida Superorder: Dinosauria Order: Saurischia Suborder: Sauropodomorpha Superfamily: Titanosauriformes Family: Brachiosauridae Genus: Giraffatitan
Binomial name
Giraffatitan brancai Paul, 1988

Giraffatitan ("giraffe titan") was a sauropod dinosaur of the family Brachiosauridae from Jurassic Africa, originally named as an African species of Brachiosaurus (B. brancai). In 1988, Gregory S. Paul noted that the African form (on which most popular depictions of Brachiosaurus are based) showed significant differences from the North American form (B. altithorax), especially in the proportions of its trunk vertebrae and in its more gracile build. Paul used these differences to create a sub-genus he named Brachiosaurus (Giraffatitan) brancai. In 1991, George Olshevsky asserted that these differences are enough to place the African brachiosaur in its own genus, simply Giraffatitan. Although this name has frequently appeared on the Internet, it has rarely been used in the scientific literature outside of Paul (1988) and Olshevsky (1991).

Possibly adding further differences between the two species was the description in 1998 of a North American brachiosaur skull (Carpenter & Tidwell, 1998). This skull, which had been found nearly a century earlier (it is the skull Marsh used on his early reconstructions of Brontosaurus), is identified as Brachiosaurus sp. and may well belong to B. altithorax. The skull is more camarasaur-like than the distinctive high-crested skull of B. brancai/Giraffatitan, so if it does belong to Brachiosaurus, it would lend a great deal of support to the existence of Giraffatitan as a distinct genus.

[edit] References

• Kenneth Carpenter and Virginia Tidwell. (1998). "Preliminary description of a Brachiosaurus skull from Felch Quarry 1, Garden Park, Colorado." In: The Upper Jurassic Morrison Formation: An Interdisciplinary Study. Kenneth Carpenter, Danial Chure and James Kirkland eds. Modern Geology Vol. 23 No 1-4. pp. 69-84.

• Olshevsky, George. 1991. A Revision of the Parainfraclass Archosauria Cope, 1869, Excluding the Advanced Crocodylia. Mesozoic Meanderings #2 (1st printing): iv + 196 pp.

• Paul, G. S. 1988. The brachiosaur giants of the Morrison Tendaguru with a description of a new subgenus, Giraffatitan, and a comparison of the world's largest dinosaurs. Hunteria 2 (3): 1-14.