Unveiling the chewing lice (Menoponidae and Philopteridae) fauna of the Brazilian Northeast: new records for Maranhão and Piauí States.

Lice (Phthiraptera) are obligate ectoparasites of birds and mammals found worldwide. Chewing lice, belonging to the families Menoponidae and Philopteridae, are particularly diverse in Brazil, although their distribution is unevenly documented across states. This study focused on recent collections from protected areas in Maranhão and Piauí, the sampling involved mist netting and comprehensive ectoparasite examination, with specimens identified using both light microscopy and Scanning Electron Microscopy. A total of 239 birds were collected, 63 (26.35%) of which were infested with chewing lice. Seventeen distinct species were identified, including seven that had not been previously recorded in Brazil. Our findings contribute to the growing knowledge of chewing lice diversity in Brazil, with particular emphasis on the underrepresented states of Maranhão and Piauí.