The Curve-winged Sabrewing occurs in the eastern Sierra Madre Oriental of Mexico. An 1887 regional account describes the male with a blue crown, bronze-green upperparts and iron-grey underparts.
An 1887 Mexican account describes a male with a metallic ultramarine crown, bronze-green upperparts, iron-grey throat, breast and belly, and chestnut-tinged undertail coverts. It says the female is similar but slightly smaller and less blue on the crown.
A historical report says the bird occurred occasionally near Jalapa and more often around Coatepec, where it used forest in winter and fed at flowers on tall shrubs. Few were seen there in summer; the author had not seen or heard of a nest in that locality.
An extinction-risk assessment has not been added yet.