Caddisflies (Trichoptera) checklist and a new species of von Siebold, 1856, from the Brejo de Altitude de Triunfo, a relict rainforest within the Caatinga domain, Northeast Brazil.

Brejos de Altitude are evergreen seasonal forests, associated with plateau regions in the middle of the Caatinga domain in Northeast Brazil, which possibly acted as biological corridors between the Atlantic Forest and the Amazon rainforest during the Pleistocene. The first entomological survey in the highest point in the state of Pernambuco, Brazil, the Brejo de Altitude de Triunfo, was implemented and resulted in a checklist of caddisflies with six families, nine genera, and eleven species, including a new species. is described and illustrated, based on all semaphoronts. A key to Brazilian Helicopsyche (Feropsyche) Johanson, 1998 species is also provided. In addition to the caddisfly survey in the Brejos de Altitude, the results include new records for the state, region, and also for the country. Thus, this study updates the number of species in the Brazilian Northeast region and Pernambuco state to 169 species and 43 species, respectively.