[D] Majungatholus atopus [Su] [jG]
Sues & Taquet, 1979
Cretaceous Late Campanian
Saurischia Theropoda Abelisauridae
Gres de Maevarano, Majunga, Madagascar
Genus - Skull
Majungasaurus (Lavocat, 1955) > Majungasaurus crenatissimus (Deperet, 1896) >> Megalosaurus crenatissimus (Deperet, 1896)
Majungasaurus > Majungatholus atopus (Sues & Taquet, 1979)
O\\\\\\\'Connor and Claessens , (2005) reported on the basis of a comparative analysis of region-specific pneumaticity with extant birds, evidence for cervical and abdominal air-sac systems in non-avian theropods, along with thoracic skeletal prerequisites of an avian-style aspiration pump.The authors demonstrated by examination of an exceptional new specimen of Majungatholus atopus, (Majungasaurus), documenting these features in a taxon only distantly related to birds. Taken together, these specializations imply the existence of the basic avian pulmonary Bauplan in basal neotheropods, indicating that flow-through ventilation of the lung is not restricted to birds but is probably a general theropod characteristic.\\\\\\\"
Majungatholus closely resembles Carnotaurus sastrei found in Argentina that most experts had considered a strange South American\\\\\\\' offshoot of the dinosaur clan. Majungatholus atopus provides important clues about how the continents broke up and driftedd during the 150-million-year reign of the dinosaurs, the Madagascar discovery suggests that South America, India and Madagascar were all connected by a land bridge, probably Antarctica, when the animal species developed. Because no such specimens have been found in Africa Majungatholus supports, but does not prove, that Africa was an \\\\\\\"island continent\\\\\\\" 70 million years ago.
With a total body length of almost 30 feet, Majungatholus was the top predator of the time on Madagascar. For more than a century theropod dinosaurs are known from Madagascar but almost solely on the basis of isolated teeth -- hundreds of them, each with tiny serrations indicating the predatory habits of the animal.
Majungatholus was originally named for an isolated skull fragment thought to belong to a pachycephalosaur, or dome-headed dinosaur. Sampson et. al. proved the new skull, with an equivalent bony bump above the eye sockets, was not a \\\\\\\"bone-head\\\\\\\" at all, but that it is actually a bone-headed an abelisaur. Two abelisaurs are already known to have thickened cranial elements - Carnotaurus sastrei and Indosaurus matleyi. In Carnotaurus sastrei the frontal elements were developed as pointy horns; in Indosaurus, the bulging frontals may represent the bases of horn cores.