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.
Largest organisms
The Permian era "Cotylorhynchus", from what is now the southern United States, probably was the largest of all synapsids (most of which became extinct 250 million years ago), at and 2 tonnes. The largest carnivorous synapsid was "Anteosaurus" from what is now South Africa during Middle Permian era. "Anteosaurus" was long, and weighed about .The largest living reptile, a representative of the order Crocodilia, is the saltwater crocodile ("Crocodylus porosus") of Southern Asia and Australia, with adult males being typically long. The largest confirmed saltwater crocodile on record was long, and weighed about . Unconfirmed reports of much larger crocodiles exist, but examinations of incomplete remains have never suggested a length greater than . Also, a living specimen estimated at and has been accepted by the Guinness Book of World Records. However, due to the difficulty of trapping and measuring a very large living crocodile, the accuracy of these dimensions has yet to be verified. A specimen named Lolong caught alive in the Philippines in 2011 (died February 2013) was found to have measured in length.