A review of the Neotropical microcaddisfly genus Acostatrichia Mosely, 1939 with description of a new species from Brazil (Trichoptera: Hydroptilidae: Leucotrichiinae)
The microcaddisfly genus Acostatrichia Mosely (Leucotrichiinae, Leucotrichiini) is revised. Based on morphological features of the adult male, species assigned to the genus are here divided into three species groups: A. plaumanni Group, A. brevipenis Group, and A. cerna Group. After examination of type specimens, the subjective synonymy of Acostatrichia darda Oláh & Flint, A. hosulaba Oláh & Flint, and A. pika Oláh & Flint is proposed, with the first name being chosen to have priority over the other two. Acostatrichia ketvilla Oláh & Flint is considered a junior synonym of Costatrichia nelsonferreirai Santos & Nessimian, and another 3 species are removed from Acostatrichia: A. tapada Oláh & Flint and A. rovidka Oláh & Flint are transferred to Costatrichia; and A. topora Oláh & Flint is transferred to Leucotrichia Mosely. A new species, Acostatrichia araca sp. nov. is described and illustrated from northern Brazil; descriptions and illustrations are also provided for the other 11 Acostatrichia species. After these nomenclatural acts, the genus Acostatrichia includes 15 species restricted to South America.