The Inca is the most aberrant member of its family and is placed in its own monotypic genus. Its body is charcoal grey, with dark black primaries and black cap, and bright red bill and legs. The most distinctive feature of this species are its prominent white moustaches which, starting at the base of the bill, are quite long and curl down around the cheek. The Inca Tern is primarily coastal occurring from north central Chile to Ecuador. It is quite common along near shore waters where it forages for anchovetta but are most easily found along rocky coasts where they breed on sea cliffs and guano islands. Though highly distinctive at close range, from a distance, this species can easily be confused with the Grey Gull, especially juveniles, but note structure and especially on the adult, the bright red bill.