Data from tails of coelurosaurian theropods.

2× = mid-caudal centra at least twice as long as proximal caudal centra. E = cranialmost caudal centrum with suddenly marked elongation (length/height) as compared to more proximal caudal centra. NC = number of caudal vertebrae. PZ = cranialmost caudal contributing to caudotheca. C = cranialmost caudal contacted by caudotheca. TP = distalmost caudal with transverse process as a distinct process (not just a low ridge). TrPt = Abrupt transition point present. Numbers in parentheses under “NC” indicate estimated number of additional vertebrae beyond those preserved in the specimen. Hyphens indicate inapplicability. For cases in which data were collected directly from a specimen or cast, the specimen number is given. Institutional abbreviations: AMNH = American Museum of Natural History, New York City, New York, United States of America. IGM = Mongolian Institute of Geology, Ulaan Baatar, Mongolia. IVPP = Institute of Vertebrate Paleontology and Paleoanthropology, Beijing, People’s Republic of China. MPCA = Museo Carlos Ameghino, Cipolletti, Rio Negro Province, Argentina. UA = Université d’Antananarivo, Antananarivo, Madagascar. UMNH = Utah Museum of Natural History, Salt Lake City, Utah, United States.