Albertonykus Albertonykus

Albertonykus (meaning “Alberta claw”) is an extinct genus of alvarezsaurid dinosaur from the Maastrichtian-age (Upper Cretaceous) rocks of the Horseshoe Canyon Formation of Alberta, Canada. It is known from forelimb and hindlimb remains from multiple individuals. All but two of the specimens come from a bonebed dominated by Albertosaurus, located at the top of Unit 4 of the Horseshoe Canyon Formation, dating to ~68.5 million years ago.

Albertonykus is interpreted as having fed on wood-nesting termites because the forelimbs appear specialized for digging but are too short for burrowing. Albertonykus is the earliest known North American alvarezsaurid. Isolated bones of alvarezsaurids are known from late Maastrichtian rocks in Montana and Wyoming (USA). The bones now belonged to a new genus, Trierarchuncus.