Dinosaurs A to Z
Alvarezsauridae

Trierarchuncus

"captain hook,"

Generic theropod body-plan outline
You 1.8 m (5.9 ft) tall
Trierarchuncus 5 m (16.4 ft) long
as long as 3 people standing fingertip to fingertip
generic theropod body plan, scaled to length — not a silhouette of Trierarchuncus
Length
5 m (16.4 ft)
Period
Late Cretaceous (66.2–66 Mya)
Place
Montana, USA
Food
Carnivore
Clade
Alvarezsauridae

Trierarchuncus (meaning “captain hook,” after its single-clawed hands) is a monotypic genus of alvarezsaurid theropod which includes a single species, Trierarchuncus prairiensis, mainly known from fossils found in deposits of the Hell Creek Formation in Montana. It is the youngest known alvarezsaurid and one of the last non-avian dinosaurs, going extinct during the Cretaceous–Paleogene extinction event, which occurred approximately 66 million years ago.

What we know

  • Named by Fowler et al., 2020.
  • Fossils found in Montana, USA.

What we guess

The reconstruction notes for Trierarchuncus — soft tissue, color, behavior — haven't been written up yet. Only the recorded basics above are filled in so far.