RESUMEN
A new species of Trichobius Gervais, 1844 (Diptera: Streblidae) is described from specimens collected in Jalisco, Mexico, from host bat Choeronycteris mexicana Tschudi. We place the new species within the "dugesii" group, because it shares certain characteristics with Trichobius urodermae Wenzel, 1966 T. angulatus Wenzel, 1976 and T. tiptoni Wenzel, 1976. However, it is easy to differentiate from all known species due to the chaetotaxy of the thorax, in which the prescutal and lateral setae are very long, while the discal setae are abruptly smaller and denser. It also possesses the metasternal lobe, which is very broad and translucent. We found a male of Paratrichobius americanus Peterson & Ross, 1972 on the same host individual, which expands the distribution area of P. americanus into Mexico because the unique holotype was collected in Arizona.