Hallopus victor

Hallopus is an extinct genus of small "sphenosuchian" crocodylomorph, known from the Late Jurassic Morrison Formation of North America. The only known species Hallopus victor was originally named in 1877 as a species of the dinosaur Nanosaurus, and was moved into its own genus by Othniel Charles Marsh in 1881. It was a quite small animal, reaching a length of 1 m (3.3ft) with long and slender limbs. Macelognathus, a similarly slender-proportioned crocodylomorph to Hallopus, may be synonymous with it.

==History and naming== thumb|Front and hind limb of Hallopus victor|left The holotype specimen of Hallopus was discovered by near Canyon City, Colorado and acquired by a collector named Baldwin for three dollars in a local curiosity shop in Colorado Springs. According to letters later chronicled by Schuchert (1939), he found out about the fossil after hearing about the discovery of a supposed fossil bird, before later traveling to the type locality himself in search of additional remains.