School of Earth and Environmental Sciences, Seoul National University, Seoul, 08826, South Korea.
Department of Biological Sciences, CW 405 Biological Sciences Building, University of Alberta, Edmonton, AB, T6G 2E9, Canada.
Sci Rep. 2021 Mar 18;11(1):4101. doi: 10.1038/s41598-021-83568-4.
A new articulated postcranial specimen of an indeterminate ankylosaurid dinosaur from the Upper Cretaceous (middle-upper Campanian) Baruungoyot Formation from Hermiin Tsav, southern Gobi Desert, Mongolia includes twelve dorsal vertebrae, ribs, pectoral girdles, forelimbs, pelvic girdles, hind limbs, and free osteoderms. The new specimen shows that Asian ankylosaurids evolved rigid bodies with a decreased number of pedal phalanges. It also implies that there were at least two forms of flank armor within Ankylosauridae, one with spine-like osteoderms and the other with keeled rhomboidal osteoderms. Unique anatomical features related to digging are present in Ankylosauridae, such as dorsoventrally flattened and fusiform body shapes, extensively fused series of vertebrae, anteroposteriorly broadened dorsal ribs, a robust humerus with a well-developed deltopectoral crest, a short robust ulna with a well-developed olecranon process, a trowel-like manus, and decreased numbers of pedal phalanges. Although not fossorial, ankylosaurids were likely able to dig the substrate, taking advantage of it for self-defence and survival.
来自蒙古南部戈壁沙漠 Hermiin Tsav 的上白垩统（中上部坎潘期） Baruungoyot 组的一个不确定的甲龙类恐龙的新关节后体标本，包括十二个背椎、肋骨、肩带、前肢、腰带、后肢和游离的骨板。新标本表明亚洲甲龙类进化出了具有减少的跖骨数量的刚性身体。它还表明，在甲龙科中至少有两种形式的侧甲，一种具有脊椎状的骨板，另一种具有龙骨状的菱形骨板。与挖掘有关的独特解剖特征存在于甲龙科中，例如背腹扁平的和梭形的身体形状、广泛融合的一系列脊椎、前后方向变宽的背肋骨、肱骨粗壮并有发达的肩峰嵴、短而粗壮的尺骨有发达的鹰嘴突、类似抹刀的手和减少的跖骨数量。尽管不是穴居动物，但甲龙类可能能够挖掘基质，利用它进行自我防御和生存。
