Tonkinosoma flexipes Jeekel, 1953

Liu, Weixin & Golovatch, Sergei, 2018, Occurrence of the millipede genus Tonkinosoma Jeekel, 1953 in China, with the description of the first presumed troglobitic species of this genus (Diplopoda, Polydesmida, Paradoxosomatidae), ZooKeys 742, pp. 23-34 : 24-25

Tonkinosoma flexipes Jeekel, 1953 Figs 1, 2, 3

Tonkinosoma flexipes Jeekel, 1953: 1, figs 1-4.

Tonkinosoma flexipes - Nguyen 2011: 68.

Material examined.

9 ♂, 1 ♀ (SCAU), 2 ♂ (ZMUM), China, Guangxi, Hechi City, Fengshan County, Jinya Town, Hangdong Village, 24°37'44"N, 106°51'26"E, 500 m a.s.l., 14.VI.2014, leg. Mingyi Tian, Weixin Liu, Haomin Yin & Xiaozhu Luo.

Remarks.

This is the type species of Tonkinosoma hitherto known only from a highly detailed original description, based on the male holotype and two paratypes, one male and one female, all from Mt Manson, Langson Province, northern Vietnam ( Jeekel 1953). Above is only the second record of T. flexipes , a species new to the fauna of China, but this is hardly too surprising because it comes from a place quite close to the border with northern Vietnam. The new samples almost fully agree with the original description ( Jeekel 1953), but our material is remarkably smaller (19-28 mm vs. 37-47 mm). The habitus and gonopod structure (Figs 1-3) are illustrated to document the species’ identity. Among the main diagnostic characters of T. flexipes , the following seem to be especially noteworthy to complement the only available description: integument strongly shining; metazonae with several longitudinal striae above paraterga (Fig. 2C); pleurosternal carinae present on segments 2-4 in both sexes (Fig. 2C); a large, median, subquadrate process between ♂ coxae 4 and two small, independent tuberculations between ♂ coxae 5 (Fig. 2F); legs ca 1.6 (♂) or 1.2 (♀) times as long as midbody height, tarsal brushes present on all ♂ legs (Fig. 2I); gonopodal postfemoral part only indistinctly demarcated, lamina lateralis well-developed only in the proximal part of the solenophore (Fig. 3).