South Hills crossbill

The South Hills crossbill (Loxia curvirostra sinesciuris) is a passerine bird in the family Fringillidae. It is endemic to the South Hills and Albion Mountains in southern Idaho. South Hills crossbill rarely interbreeds with other call types that move into the South Hills of Idaho yearly, and can be considered to represent a distinct species via ecological speciation.

It has been proposed as a separate species, but the American Ornithologists' Union failed to find consensus on the issue in 2009 and thus the South Hills crossbill is still considered a subspecies of the red crossbill.