Brachypodosaurus

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Brachypodosaurus
Temporal range: Late Cretaceous, 66 Ma
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Sauropsida
Superorder: ?Dinosauria
Order: ?Ornithischia
Suborder: ?Thyreophora
Infraorder: ?Ankylosauria
Genus: Brachypodosaurus
Chakravarti, 1934
Species: B. gravis
Chakravarti, 1934
Binomial name
Brachypodosaurus gravis

Brachypodosaurus (meaning "short-footed lizard") is a dubious genus of possibly thyreophoran dinosaur from the Late Cretaceous Lameta Formation (Maastrichtian) in India.

The only remains discovered so far for this animal consist of a single fossil bone, excavated at the Chota Simla Hill near Jabalpur. In 1934, geologist Dhirendra Kishore Chakravarti, of the Geological Museum of the Banaras Hindu University, considered it a humerus, of a stegosaurian. He named it as the type species Brachypodosaurus gravis. The generic name is derived from Greek βραχύς, brachys, "short", and πούς, pous, "foot". The specific name gravis means "heavy" in Latin.[1] Chakravarti hereby became the first local scientist to name a dinosaur.

The holotype is IM V9. The bone is over a foot long. Chakravarti based his identification of the element as a humerus on the presence of a large crest on the shaft, which he took for the deltopectoral crest. The status as a (dinosaurian) humerus is problematic. The bone is flat, has a crest on the other side of the shaft also, is not twisted around its longitudinal axis, is strongly constricted above and below the crests and lacks a clear caput or condyles. In any case, it lacks stegosaurian synapomorphies.[2] On the assumption it might at least be some member of the Thyreophora, it has been considered a possible ankylosaurian, the ankylosaurs being a sister group of the Stegosauria that survived into the Late Cretaceous. Even then, however, it was considered a nomen dubium as so few remains of the animal have been found.[3] In 2004, Matthew Lamanna e.a. considered it unlikely that any Ornithischia were present in the Maastrichtian of India.[4] The other Late Cretaceous genus from India originally described as a stegosaur, Dravidosaurus, is also a nomen dubium based on plesiosaurian remains.

References[edit]

  1. ^ Chakravarti, D. K., 1934, "On a stegosaurian humerus from the Lameta beds of Jubbulpore", Quarterly Journal of the Geological, Mining, and Metallurgical Society of India, 30; 75-79
  2. ^ Wilson, J. A., P. C. Sereno, S. Srivastava, D. K. Bhatt, A. Khosla, and A. Sahni. 2003. "A new abelisaurid (Dinosauria, Theropoda) from the Lameta Formation (Cretaceous, Maastrichtian) of India", Contributions from the Museum of Paleontology of the University of Michigan, 31:1–42
  3. ^ Maryanska T., 1977. "Ankylosauridae (Dinosauria) from Mongolia", Palaeontologia Polonica 37:85-151
  4. ^ Lamanna, M.C., J.B. Smith, Y.S. Attia, and P. Dodson, 2004, "From dinosaurs to dyrosaurids (Crocodyliformes): removal of the post-Cenomanian (Late Cretaceous) record of Ornithischia from Africa", Journal of Vertebrate Paleontology 24: 764-768