White Matt A, Bell Phil R, Poropat Stephen F, Pentland Adele H, Rigby Samantha L, Cook Alex G, Sloan Trish, Elliott David A
School of Environmental and Rural Science, University of New England, Armidale, New South Wales 2351, Australia.
Australian Age of Dinosaurs Natural History Museum, The Jump-Up, Winton, Queensland 4735, Australia.
R Soc Open Sci. 2020 Jan 15;7(1):191462. doi: 10.1098/rsos.191462. eCollection 2020 Jan.
The holotype specimen of the megaraptorid , from the Upper Cretaceous Winton Formation (Rolling Downs Group, Eromanga Basin) of central Queensland, is the most complete non-avian theropod found in Australia to date. In fact, the holotype of and isolated megaraptorid teeth (possibly referable to ) constitute the only theropod body fossils reported from the Winton Formation. Herein, we describe a new fragmentary megaraptorid specimen from the Winton Formation, found near the type locality of . The new specimen comprises parts of two vertebrae, two metatarsals, a pedal phalanx and multiple unidentifiable bone fragments. Although the new megaraptorid specimen is poorly preserved, it includes the only megaraptorid vertebrae known from Queensland. The presence of pleurocoels and highly pneumatic caudal centra with camerate and camellate internal structures permit the assignment of these remains to Megaraptora gen. et sp. indet. A morphological comparison revealed that the distal end of metatarsal II and the partial pedal phalanx II-1 of the new specimen are morphologically divergent from . This might indicate the presence of a second megaraptorid taxon in the Winton Formation, or possibly intraspecific variation.
这种巨型盗龙类的正模标本采自昆士兰州中部上白垩统温顿组（埃罗曼加盆地罗林唐斯群），是迄今为止在澳大利亚发现的最完整的非鸟类兽脚亚目恐龙。事实上，该正模标本以及一些孤立的巨型盗龙类牙齿（可能属于该物种）是温顿组报道过的仅有的兽脚亚目恐龙身体化石。在此，我们描述一件来自温顿组、在正模标本产地附近发现的新的巨型盗龙类破碎标本。新标本包括两块脊椎骨碎片、两块跖骨、一块足趾骨以及多个无法辨认的骨骼碎片。尽管新的巨型盗龙类标本保存状况不佳，但它包含了昆士兰州已知的仅有的巨型盗龙类脊椎骨。侧腔以及具有蜂巢状和小室状内部结构的高度充气的尾椎椎体的存在，使得这些遗骸可以归入巨型盗龙类属（未定种）。形态学比较显示，新标本的第二跖骨远端和部分第二趾骨在形态上与（另一标本）不同。这可能表明温顿组存在第二个巨型盗龙类分类单元，或者可能是种内变异。
