AbstractBackgroundIschnothyreusSimon, 1893 is one of the most speciose genera ofOonopidae, with 124 extant species mainly distributed in the Old World. Currently, 27 species are known in China.New informationA new species,IschnothyreusruyuanensisTong, sp. n., is described from Guangdong Province, China. Morphological description and illustrations are provided.