Xystodesmus nikkoensis ( Chamberlin & Wang, 1953 )

Korsós, Zoltán & Nakamura, Yasuyuki, 2025, Review of the millipede genus Xystodesmus (Diplopoda, Polydesmida), with seven new species from the southwestern part of Japan, ZooKeys 1231, pp. 191-232 : 191-232

Xystodesmus nikkoensis ( Chamberlin & Wang, 1953)

Fig. 17 E, F

Nikkonus nikkoensis Chamberlin & Wang, 1953: 9, fig. 3

Xystodesmus nikkoensis : Tanabe and Shinohara 1996: 1484, figs 3–7, 11 J – K, 13 A, 16 A, 17 L, M

Material examined.

• 4 males, Japan, Northern Ryukyus, Kagoshima Pref., Osumi Group, Yaku-shima Isl., Anbo forest road , Cryptomeria japonica forest, 30°18'42.0"N, 130°37'54.0"E, 190 m a. s. l., 5 July 2010, leg. Z. Korsós ( HNHM diplo-04551 ) .

Descriptive notes.

Tanabe and Shinohara (1996) gave a short redescription and showed relatively small variability in the male gonopod structure. Our specimens, collected exactly on the original type locality (“ Anbo Rindo ”, Yaku-shima Island) are in complete agreement. Tanabe and Shinohara (1996, p. 1484) also said X. nikkoensis is “ the smallest species of xystodesmid in Japan ”. This statement, however, in light of the present discovery of the new species X. parvus sp. nov. and X. sesokoensis sp. nov., is not true anymore.

Colour of living specimens

(Fig. 17 E, F ). According to Tanabe and Shinohara (1996: 1484) Yaku-shima specimens have on “ collum and metatergites with yellowish white paranotal spots ”. Based on our freshly photographed animals also from Yaku-shima Isl., we can support this observation and can add that those paranotal spots are even more conspicuous next to the entirely dark brown body colour.

Figures

Figure 17. Live habitus of Xystodesmus millipedes A, B X. variatus (Pocock, 1895) males, Kouri-jima Isl., Okinawa Pref. C, D X. martensii (Peters, 1864) males C Eno-shima Isl., Kanagawa Pref. D Mt. Oyama, Kanagawa Pref. E, F X. nikkoensis (Chamberlin & Wang, 1953) males, Yaku-shima Isl., Kagoshima Pref. Not to scale.