What is Troodontidae?

Troodontidae is a group of bipedal, probably feathered, lightly built, deinonychosaurian theropod dinosaurs that are notable for their small body size but large relative brain size and keen senses, and are widely hypothesized to be among the closest extinct relatives of birds.

Like dromaeosaurids, most troodontids (members of Troodontidae) were "didactyl", meaning they walked on only two toes. They had a third toe (which, funnily enough, was the "second" toe or digit II) that was adorned with a large curved claw indicative of a predatory lifestyle. But it was held clear of the ground to keep it in tip-top shape.

Click here to search Dinochecker for troodontids. Troodontidae is derived from the Greek "troo" (wound, injure, pierce) and "odon" (tooth), and the Latin "idae" (family), named for the group anchor Troodon who was named for its curved teeth with jagged, upwards-pointing serrations. Funnily enough, that kind of teeth are common in herbivores, and the teeth of some troodontids lack serrations altogether.