Pipistrellus hesperus (H. Allen, 1864) . Smithson. Mise. Coll., 7:43.

TYPE LOCALITY: USA, California, Imperial Co., Old Fort Yuma .

DISTRIBUTION: Washington to SW Oklahoma (USA), and Baja California, south to Hidalgo and Guerrero (Mexico).

SYNONYMS: apus, australis, maximus, merriami, oklahomae, potosinus, santarosae.

COMMENTS: Subgenus Hypsugo .