Apsaros

Apsaros is a genus of extinct birds that lived during the Eocene epoch. These birds are known from fossil remains found in North America, primarily in the Green River Formation of Wyoming. Apsaros belongs to the family Pelagornithidae, a group of large, extinct seabirds characterized by their tooth-like projections on their beaks, although Apsaros is considered a basal member and these projections are less developed than in some of its relatives.

The fossils of Apsaros indicate a bird that was likely a marine or coastal predator. Its skeletal structure suggests adaptations for flight, and its beak morphology points to a diet of fish and squid. The Green River Formation is known for preserving a wide array of fossilized life, and the presence of Apsaros there provides insights into the ancient ecosystems of the Eocene.

The genus Apsaros currently includes at least one described species, Apsaros gallicus. The discovery of Apsaros contributes to our understanding of the evolution and diversification of birds, particularly the specialized lineage of pelagornithids. These ancient birds occupied a niche in marine environments that is now filled by various modern seabirds. Research on Apsaros continues to shed light on the paleoecology and evolutionary history of avian life.