Xystodesmus Cook 1895

Genus Xystodesmus Cook, 1895 Takakuwaia Verhoeff, 1936a: 152–153 (with type species T. furculigera Verhoeff, 1936), synonymized by Hoffman (1956: 96). Cyphonaria Verhoeff, 1936a: 160–161 (with type species Fontaria (Cyphonaria) scabra Verhoeff, 1936, originally as a subgenus), synonymized by Hoffman (1980: 156). Koreoaria Verhoeff, 1937: 319 (with type species of K. palllida Verhoeff, 1937), synonymized by Korsós & Nakamura (2025: 193). Phrurodesmus Takakuwa, 1943: 604 (with type species P. gracilipes Takakuwa, 1943), synonymized by Tanabe & Shinohara (1996: 1472). Nikkonus Chamberlin & Wang, 1953: 9 (with type species N. nikkoensis Chamberlin & Wang, 1953), synonymized by Tanabe & Shinohara (1996: 1472). Type species Polydesmus (Fontaria) Martensii Peters, 1864, by original designation. Diagnosis A typical xystodesmid which differs from the closely related Riukiaria Attems, 1938 by a smaller body size (usually under 30 mm), brownish or greyish tergites with conspicuous red, orange or yellow paranotal spots, and the gonopod conformation, especially the two well-developed processes (prefemoral and acropodite) with various additional appendages (Korsós & Nakamura 2025). Species included The genus includes 20 species: Xystodesmus amoenus (Takakuwa, 1942), X. bazanensis (Takakuwa, 1942) comb. nov., X. bifurcus sp. nov., X. fasciatus Korsós & Nakamura, 2025, X. gracilipes (Takakuwa, 1943), X. keramae Korsós & Nakamura, 2025, X. kumamotoensis Korsós & Nakamura, 2025, X. kumeensis Korsós & Nakamura, 2025, X. martensii (Peters, 1864), X. nikkoensis (Chamberlin & Wang, 1953), X. pallidus (Verhoeff, 1937), X. parvus Korsós & Nakamura, 2025, X. rebekae Korsós & Nakamura, 2025, X. saltuosus (Haga 1968), X. serrulatus (Miyosi, 1952), X. sesokoensis Korsós & Nakamura, 2025, X. shirozui (Takakuwa, 1942), X. tokaiensis Tanabe & Shinohara, 1996, X. variatus (Pocock, 1895), X. yamamiensis Masuda, 2001. Distribution The genus Xystodesmus is distributed predominantly on the Japanese islands of Honshu, Shikoku, and Kyushu, and in the northern and central Ryukyu Islands (Kagoshima and Okinawa Prefectures). Two species of Koreoaria (Koreoaria amoena and K. pallida) have recently been allocated to Xystodesmus (Korsós & Nakamura 2025), and with the present paper, three more (Xystodesmus bazanensis comb. nov., X. bifurcus sp. nov., X. shirozui) are confirmed for the Korean Peninsula, increasing the number of species occurring there to five.