Genus Grandilithus Liu & Li, 2022

Type species. Grandilithus anyuan Liu & Li, 2022

Comments. This genus includes 28 species recorded from China (28 records) and Japan (2 records), mainly from Jiangxi, Fujian, Hunan, Hainan, Guangxi Zhuang Autonomous Region, and Taiwan regions (Liu et al. 2022); five species are known only from males and six are known only from females. However, the species of Otacilia pinglong Liang, Li, Yin, Li & Xu, 2021 and O. pseudofabiformis Liang, Li, Yin, Li & Xu, 2021 are only known from the female, and their unknown males may have palpal modifications like palpal femur with a strong, gloveshaped ventral extension on the subdistal part, the tegulum with only one apophysis and the thin embolus curved into a semicircle.