Xystodesmus martensii (Peters, 1864)

Fig. 17 C, D

Polydesmus (Fontaria) martensii Peters, 1864: 531, no fig.

Xystodesmus martensii: Cook 1895: 5, no fig.

Material examined.

• 4 males, 3 females, Japan, Honshu, Kanagawa Pref., Fujisawa City, Eno-shima Isl., Kodama Shrine, 35°18'03"N, 139°28'52"E, 20 m a. s. l., oak grove, 11 October 2010, leg. Z. Korsós and Y. Nakamura (HNHM diplo-04549) ; • 3 males, 4 females, Japan, Honshu, Kanagawa Pref., Isehara City, Mt. Oyama, Yabitsu Pass, 760 m a. s. l., 35°25'36"N, 139°14'05"E, Cryptomeria japonica forest, 11 October 2010, leg. Z. Korsós and Y. Nakamura (HNHM diplo-04550) ; 1 male, Japan, Honshu, Kanagawa Pref., Yamakita Town, Yuzuku, Myojin Pass, 12 October 2010, leg. Y. Nakamura (RUMF -ZD-00935)

Descriptive notes.

Tanabe and Shinohara (1996) gave an extensive redescription of the species based on their new material and have shown great variation in the shape of male gonopods. The gonopods of the eight males we studied here fit within the range of variation described by Tanabe and Shinohara (1996). We also noticed the conspicuous metatergal tubercles, which are much more developed than in other Xystodesmus species.

Colour of living specimens

(Fig. 17 C, D). The Kanagawa samples represent two slightly different colour morphs: one pale greyish, the other one dark brown, but both have the typical and strong, reddish orange spots on paranota.