Gillirhynchops has a number of sharp teeth in its mouth that partially serve to filter plankton.

Gillirhynchops swallows small stones to act as Gastroliths to help break down fish that it swallows whole.

Gillirhynchops sucks fish into its mouth with a vacuum-like suction. The second function of its hooked teeth is to prevent escape.

This dinosaur was created by dna samples taken from a single source: a Dolichorynchops fossil with a juvenile Gillicus preserved in its stomach.