[D] Allosaurus fragilis [Su] [T]
Jurassic Late Kimmeridgian Tithonian
Saurischia Theropoda Tetanurae Carnosauria Allosauridae
Morrison Formation, Colorado, Montana, New Mexico, Oklahoma, South Dakota; Cleveland-Lloyd Dinosaur Quarry, Utah, Wyoming, US; Lourinha Formation, near Andres, about 135 km NNE of Lisbon, District of Leiria, west-central Portugal
Typespecies - Skull
Allosaurus (Marsh, 1877) = Creosaurus (Marsh, 1878) Epanterias (Cope, 1878) Labrosaurus (Marsh, 1879) ?Saurophagus (Ray, 1941)
Allosaurus > Allosaurus fragilis (Marsh, 1877) Laelaps trihedrodon (Cope, 1877) Creosaurus atrox (Marsh, 1878) Epanteris amplexus (Cope, 1878) Hypsirhophus discurus (1) [partim] (Cope, 1878) Allosaurus lucaris (Marsh, 1878) Allosaurus ferox (Marsh, 1896) ?Saurophagus maximus (Ray, 1941) ?Labrosaurus ferox (Marsh, 1884) Camptosaurus amplus (Marsh, 1879) = Camptonotus amplus (Marsh, 1879) Allosaurus whitei (Pickering, 1995)
Allosaurus > ?Allosaurus tendagurensis (Janensch, 1925)
Allosaurus > Allosaurus europaeus (Mateus, Walen and Antunes 2006)
3 complete skulls, many partial skull and skull elements, many partial and complete skeletons representing at least 60 individuals.
(AMNH 680) (9.7 m; 2.3 tons) dorsals 5-7, four proximal caudal vertebrae, ilium, pubes, ischia, femur (1.008 m), tibiae, fibulae, astragali, calcaneum, metatarsus, pedal phalanges (Chure, 2001) (AMNH 5767; holotype of Epanterias amplexus) (12.1 m; 4.5 tons) axis, sixth or seventh cervical centrum, first dorsal neural arch, coracoid (328 mm long), distal metatarsal IV The largest \\\\\\\"traditional\\\\\\\" Allosaurus specimen is AMNH 680, while the Epanterias holotype is even larger. The fact a 12.1 meter specimen of a taxon normally 7-9 meters exists just shows us how much variation can uccur within a single species, and how little to trust any of our specimens as being representative of their species. [M.Mortimer]
PEREZ-MORENO, CHURE, PIRES, MARQUES DA SILVA, DOS SANTOS, DANTAS, POVOAS, CACHAO, SANZ & GALOPIM DE CARVALHO, 1999 Museu Nacional de Historia Natural, Universidade de Lisboa, Andres collection, MNHNUL/AND.001 Horizon: Lourinha Formation, Upper Kimmeridgian-Tithonian, Late Jurassic.Material: Part of the right quadrage, several vertebrae and chevrons, several dorsal ribs, and gastralia, a partial pelvis, parts of the hind limbs and several indeterminate fragments.
The holotype cannot be identified as A. fragilis or A. sp. nov., although it is definitely Allosaurus. The nearly complete specimen USNM 4734 is designated the topotype, as it comes from the same quarry as the holotype.
Allosaurus jimmadseni, is present at Dry Mesa Quarry , where Allosaurus fragilis is the only identified species at Cleveland Lloyd Dinosaur Quarry. Although these two quarries represent an impressive Allosaurus sample, neither quarry contains both species, suggesting an ecological or temporal separation.