[D] Megapnosaurus sp. cf.
Describer
Irmis, 2004
Time
Jurassic Early
Classification
Saurischia Theropoda Ceratosauria Podokesauridae
Diet
Carnivore
Fossilsite
Dark Red Beds (Zhangjiawa Member) of the Lower Lufeng Formation [= Fengjiahe Formation], Ta Ti, Yunnan, China
Fall Under
Megapnosaurus
Info
Megapnosaurus (Ivie, Slipinski, and Wegrzynowicz, 2001) > Syntarsus (Raath, 1969) > Megapnosaurus rhodesiensis (Raath, 1969) >> Syntarsus rhodesiensis (Raath, 1969) Megapnosaurus kayentakatae (Rowe, 1989) > Syntarsus kayentakatae (Rowe, 1989)
Megapnosaurus > cf. Megapnosaurus sp. (Irmis, 2004)
FMNH CUP 2089, distal humerus, proximal radius and ulna, fragments of metacarpals and phalanges; FMNH CUP 2090, right distal tarsals II and III and proximal
metatarsals II and III.
Systematic paleontology
Dinosauria Owen 1842 Owen 1842
Theropoda Marsh 1881
Coelophysoidae Holtz 1994
Megapnosaurus Ivie, Slipinski and Wegrzynowicz 2001
cf. Megapnosaurus sp.
[Podokesauridae Simmons 1965]
Simmons (1965) noted that both specimens (FMNH CUP 2089 and 2090) were found in association with the holotype of the crocodylomorph Dibothrosuchus elaphros Simmons 1965 (FMNH CUP 2081). FMNH CUP 2089 and 2090 are much too large to pertain to Dibothrosuchus, differ differ Dibothrosuchus greatly from the morphology described for Dibothrosuchus (Simmons, 1965, Wu and Chatterjee, 1993), and would also duplicate elements found in FMNH CUP 2081.
No other dinosaur remains were found with the holotype of Dibothrosuchus, so it is plausible to assume that both specimens belong chus, so it is plausible to assume that both specimens belong chus to the same individual. Furthermore, the proportions of each specimen suggest that they both belonged to an animal of the same size. It should be noted that the specimens are generally poorly preserved, and they were further damaged by preparation, presumably in the 1950s or 1960s.
FMNH CUP 2089 and 2090 represent the fi rst record of Megapnosaurus from China, and the whole of Asia. Besides from China, and the whole of Asia. Besides being some of the only well-understood theropod material from the Lufeng Formation, these specimens also increase the known diversity of the Lufeng fauna.
Megapnosaurus is known from three continents during the Early Jurassic Period, its wide geographic range makes it a possible index taxon for Early Jurassic biochronology, and strengthens the evidence for an Early Jurassic age for the Lufeng Formation.
Finally, the fact that Megapnosaurus and other terrestrial tet- and other terrestrial tet- rapods were pancontinental during the Early Jurassic suggests that the breakup of Pangaea did not present serious barriers to dispersal of terrestrial vertebrates.