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''Balaur bondoc'' is a species of theropod dinosaurs which lived in what is now Romania during the late Cretaceous period. It is the type species of the monotypic genus ''Balaur'' which was described by scientists in August 2010, and was named after the ''balaur'' ((:baˈla.ur)), a dragon of Romanian folklore. The specific name ''bondoc'' means "stocky", so ''Balaur bondoc'' means "Stocky dragon" in Romanian. This name refers to the greater musculature that ''Balaur'' had compared to its relatives. The genus is known from two partial skeletons including the type specimen. Seventy million years ago, world sea levels were higher, and the location where its fossils are found was a part of the European Archipelago called Hațeg Island which is also referred to as the "Island of the Dwarf Dinosaurs". Unlike other early members of the group Paraves, which includes ''Velociraptor'', ''Troodon'', and ''Archaeopteryx'', this theropod had not just one but two large, retractable, sickle-shaped claws on each foot, and its limbs were proportionally shorter and heavier than those of its relatives. As with other dinosaurs from Hațeg, such as ''Magyarosaurus'', a dwarf sauropod,〔 its strange features have been argued to show the effects of its island habitat on its evolution. == Description == ''Balaur'' is a genus of theropod dinosaurs estimated to have lived about years ago in the late Cretaceous (Maastrichtian), and contains the single species ''B. bondoc''.〔 The bones of this species were shorter and heavier than those of other basal paravians. While the feet of most early paravians bore a single, large "sickle claw" on the second toe which was held retracted off the ground, ''Balaur'' had large retractable sickle claws on both the first and second toes of each foot.〔 In addition to its strange feet, the type specimen of ''Balaur'' is unique for its status of being the most complete theropod fossil from the late Cretaceous of Europe. It also possesses a great number of additional autapomorphies, including a reduced and presumably nonfunctional third finger, consisting of only one rudimentary phalanx.〔 The partial skeleton was collected from the red floodplain mudstone of the Sebeș Formation of Romania. It consists of a variety of vertebrae, as well as much of pectoral and pelvic girdles, and a large part of the limbs. It is the first reasonably complete and well-preserved theropod from the Late Cretaceous of Europe.〔 It is similar in size to ''Velociraptor'', with ''Balaurs recovered skeletal elements suggesting an overall length of around . ''Balaur'' had re-evolved a functional first toe used to support its weight, which bore a large claw that could be hyperextended. It had short and stocky feet and legs, and large muscle attachment areas on the pelvis which indicate that it was adapted for strength rather than speed.〔〔 Csiki ''et al.'' describe this "novel body plan" as "a dramatic example of aberrant morphology developed in island-dwelling taxa."〔 The stocky feet are exemplified by the length of the metatarsus being only two times its width. It is 1.5 times wider than the lower leg. Both traits are unique in the Theropoda. The skeleton of ''Balaur'' also shows extensive fusion of limb bones. Wrist bones and the metacarpals are fused into a carpometacarpus. The pelvic bones are fused. The shinbone, calf bone and the upper ankle bones have been fused into a tibiotarsus and the lower ankle bones and the metatarsals into a tarsometatarsus. The degree of fusion is typical for the Avialae, the evolutionary branch of the birds and their direct relatives.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Balaur bondoc」の詳細全文を読む スポンサード リンク
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