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 .
Sillosuchus
However, other remains indicate that it could grow much larger. Most notable among additional remains was PVL 2267, an isolated cervical (neck vertebra) initially misidentified as belonging to the giant quadrupedal predator "Saurosuchus," a distant relative of "Sillosuchus". This bone was 20 centimeters (8 inches) long, while cervicals from the holotype were only 8 centimeters (3 inches) long. Using its more complete relatives to estimate length, this bone likely belonged to a "Sillosuchus" that was 9-10 meters (30-33 feet) in length. This would indicate that "Sillosuchus" was among the largest terrestrial pseudosuchians (crocodilian-line archosaurs).