Nanosaurus agilis

Nanosaurus is a small (2 m / 6 foot long) neornithischian dinosaur from the Late Jurassic Morrison Formation of the western United States. Lightly built, with powerfully muscled legs, Nanosaurus was a fast-moving plant-eater, and probably represents the smallest-bodied ornithischians of that fauna.

The naming history of Nanosaurus has followed a long and winding road. At various times several small Morrison Formation ornithopods have been named, including Nanosaurus, Othnielia, Drinker, and Othnielosaurus. Without diving into the nitty-gritty, at this point there seems to be a weak consensus to consider them all Nanosaurus, although a recent paper by paleontologists Paul Barrett and Susie Maidment has once again called this into question. In reality these debates tend to move slowly in the sciences, and consensus can take its sweet time to shift, so for now we will go with Nanosaurus agilis, and see what happens.