Abstract. Larvae of the staphylinid subfamily Trichophyinae are described for the first time based on larvae of a new species of Trichophya from the southwestern United States. Adults and larvae of the new species, Trichophya texana Ashe & Newton (type locality Texas, Brewster Co., Big Bend National Park), are described and illustrations of both provided. Also given are a key for separation of the Nearctic species of Trichophya, a checklist of the known World fauna of the Trichophyinae (including first report of the genus from Mexico and Guatemala), and a characterization of the subfamily Trichophyinae based on both larvae and adults. The relationships of major genera and higher taxa in the tachyporine group of staphylinid subfamilies are analysed cladistically using larval characters. No larval characters were found that provide evidence for the monophyly of the tachyporine group; no evidence was found for the monophyly of the Tachyporinae; Charhyphus, Olisthaerus and Phloeocharis (Phloeocharinae + Olisthaerinae) form a monophyletic group; the Trichophyinae and Habrocerinae are sister groups and together probably are the sister group to the Aleocharinae; the Aleocharinae are confirmed to be monophyletic based on larval characters; and Gymnusa + Deinopsis form the sister group to the remainder of the Aleocharinae.