Sinosauropteryx
"Sinosauropteryx" was a small bipedal theropod, noted for its short arms, large first finger (thumbs), and long tail. The taxon includes some of the smallest known adult non-avian theropod specimens, with the holotype specimen measuring only in length, including the tail. However, this individual was relatively young. The longest known specimen reaches up to in length, with an estimated weight of .
Sacisaurus
"Sacisaurus" was approximately long and high. Its long and strong legs indicate that it was a fast animal. According to Jorge Ferigolo, paleontologist of Zoobothanic Foundation of Rio Grande do Sul state, the biggest teeth of the genus were just long.