Segisaurus (meaning "Segi canyon lizard") is a genus of small coelophysid theropod dinosaur, that measured approximately 1 metre (3.3 feet) in length. The only known specimen was discovered in early Jurassic strata in Tsegi Canyon, Arizona, for which it was named. Segisaurus is the only dinosaur to have ever been excavated from the area. Description Segisaurus lived about 183 million years ago during the Jurassic period. It was a primitive bipedal theropod roughly around the size of a goose. Segisaurus was 1 meter (3.3 feet) long, half a meter (1.65 feet) tall and weighed about 4-7 kilograms. It was nimble and insectivorous, although it may have scavenged meat also. It was bird-like in structure, with a flexible, elongated neck and stout body. Segisaurus was three-toed and had powerful legs that were long compared to its body length. Like its legs, Segisaurus had a long tail and long forearms. Its furcula bone was not unlike a bird's, thus strengthening scientists' arguments that dinosaurs were related to avians. Segisaurus is described from the only specimen ever found, the holotype UCMP 32101, which was a sub-adult. The full size of Segisaurus as an adult may never be known. Furcula were found in the Segisaurus specimen, making it one of the first known non-avian dinosaurs to preserve furcula found. These furculae were initially thought to be clavicles, which led Charles Lewis Camp to speculate that the "splint-like" neck ribs supported a Draco-like patagium along the neck, to improve the animal's ability to move quickly. Segisaurus is significant because it demonstrates that the clavicle was primitively present in early theropods. Classification Segisaurus was described in 1936 by the paleontologist Charles Lewis Camp, based on specimen UCMP 32101, a fragmentary fossil skeleton which consisted of portions of the limbs, pelvis, and vertebrae. Cranial material was not recovered. Segisaurus went relatively ignored for the next half century. When the specimen was examined during this period, all who viewed it commented on the supposed presence of clavicles and the apparently "solid" bones that the dinosaur had. Segisaurus appeared to be closely related to the better-known Coelophysis, but unlike the hollow bones of Coelophysis, Segisaurus had solid bones. This caused some scientists question whether Segisaurus was a theropod at all. In 2005, a re-examination of the Segisaurus holotype revealed that contrary to reports it did in fact have hollow bones and that the clavicles were instead fragmented furculae. In