Sinosauropteryx
"Sinosauropteryx" was a small theropod with an unusually long tail and short arms. The longest known specimen reaches up to in length, with an estimated weight of It was a close relative of the similar but older genus "Compsognathus", both genera belonging to the family Compsognathidae. Only one species of "Sinosauropteryx" has been named: "S. prima", meaning "first" in reference to its status as the first feathered non-avialian dinosaur species discovered. Three specimens have been described. The third specimen previously assigned to this genus represents either a second, as-yet unnamed species or a distinct, related genus.
Sinosaurus
"Dilophosaurus sinensis" was shown to be a junior synonym of "Sinosaurus" in 2003. It is possibly closer to the Antarctic theropod "Cryolophosaurus", based on the fact that the anterior end of the jugal does not participate in the internal antorbital fenestra and that the maxillary tooth row is completely in front of the eye socket. "D. sinensis" was exhibited in 1998 at Dinofest in Philadelphia. Although the skull of "D. sinensis" sports large nasolacrimal crests superficially like those reconstructed in "D. wetherilli", features elsewhere in the skeleton suggest it is closer to tetanuran theropods. Rauhut (2003) regarded "D. sinensis" as a basal tetanuran most closely related to "Sinosaurus" and "Cryolophosaurus". Lamanna "et al." (1998b) examined the material ascribed to "D. sinensis" and found it to be synonymous with "Sinosaurus triassicus". This cladistic finding was confirmed in 2003 by Dong.