Mononykus

Mononykus olecranus (meaning one claw) was a genus of Alvarezsauridae dinosaur from late cretaceous Mongolia. Only about 1 metre long this nimble two legged diosaur lived in the open desert plains where it could use its high speed to escape from predators. Mononykus probably ate small mammals, lizards and insects. It's large eye sockets suggest that it had very good night vision which meant it could take advantage of the cooler air and the lack of day time predators.

Mononykus was renamed in 1994 after the name it had been given a year earlier had already been taken by a beetle. Known from just a single holotype specimin which lacks a tail Mononykus previously had more remains, but they were reclassified as shuvuuia. Like most other alvarezsaurs mononykus only has one claw on each arm the purpose of these specialist arms still remains a mystery. Although no traces of feathers have been found it is still highly likely that Mononykus had feathers and is usually portraied or reconstructed with a downy layer of feathers covering its body