Abstract
The genus Sinotrisus Yin & Li, comprising four species, is redefined and revised. Members of Sinotrisus are often found with ants of the subfamily Formicinae, or in humid forest habitats. The type speciesand three new species are (re-)described and illustrated: Sinotrisus kishimotoi Yin & Nomura, sp. n. (China: Sichuan), Sinotrisus nomurai Yin, Li & Zhao (type species) (China: Zhejing), Sinotrisus sinensis Yin & Nomura, sp. n. (China: Sichuan) and Sinotrisus vietnamensis Yin & Nomura, sp. n. (Vietnam: Lai Chau). A key is included as an aid to distinguishing these species.