Desmoxytes variabilis, Liu, Weixin, Golovatch, Sergei & Tian, Mingyi, 2016

Liu, Weixin, Golovatch, Sergei & Tian, Mingyi, 2016, Six new species of dragon millipedes, genus Desmoxytes Chamberlin, 1923, mostly from caves in China (Diplopoda, Polydesmida, Paradoxosomatidae), ZooKeys 577, pp. 1-24 : 10-14

Taxon classification Animalia Polydesmida Paradoxosomatidae

Desmoxytes variabilis sp. n. Figs 1H, 12, 13, 14

Holotype

♂ (SCAU), China, Guangxi, Hechi, Fengshan Xian, Fengcheng Zhen, Cave Huoji Dong, 24°28'32"N, 107°03'28"E, ca 500 m a.s.l., 2015-VIII-3, leg. Jujian Chen, Xinhui Wang & Mingruo Tang.

Paratypes.

2 ♂, 3 ♀ (SCAU), same locality and collecting data as the holotype. 2 ♂, 1 ♀ (SCAU), 1 ♂, 1 ♀ (ZFMK), same County, Zhaiya Xiang, Laying Cun, Cave II Dong, 2015-VIII-4, leg. Jujian Chen, Xinhui Wang & Mingruo Tang. 3 ♂, 2 ♀ (SCAU), same County, Jinya Xiang, Hangdong Cun, Cave I Dong, 2014-VI-14, leg. Mingyi Tian, Weixin Liu, Haomin Yin & Xiaozhu Luo. 3 ♂, 2 ♀ (SCAU), Lingyun Xian, Sicheng Zhen, Wuzhishan, Cave Qianlongya, 2015-VI-10, leg. Mingyi Tian, Weixin Liu, Xinhui Wang & Mingruo Tang. 1 ♂, 1 ♀ (SCAU), Bama Xian, Yandong Xiang, Namen Cun, Cave Baiyan Dong, 2015-VIII-3; 3 ♂, 2 ♀ (SCAU), Tian’e Xian, Bala Xiang, Gandong Cun, Cave number VIII Dong, 2015-VIII-8. leg. Jujian Chen, Xinhui Wang & Mingruo Tang. 3 ♂, 3 ♀ (SCAU), China, Guangxi, Hechi, Huanjiang Xian, Mulun, way to Mashan Dong, 2007-V-21, leg. Louis Deharveng & Anne Bedos (CHIgx07-21-02). 2 ♂, 1 ♀ (SCAU), China, Guangxi, Hechi, Huanjiang Xian, near Midong Cun, 2007-V-23, leg. Louis Deharveng & Anne Bedos (CHIgx07-23-05).

Name.

To emphasize the metaterga showing a variable pattern of setigerous spines; adjective.

Diagnosis.

This species seems to be especially similar to Desmoxytes nodulosa Liu, Golovatch & Tian, 2014, from Cave II, Xiao’ao Xiang, Du’an Xian, Hechi, Guangxi, because both share very close patterns of metatergal ornamentation and particularly stout gonopods, but differs by the metaterga showing a variable pattern of setigerous spines, and the particularly complex gonopod solenophore.

Description.

All characters as in Desmoxytes laticollis sp. n., except as follows.

Length ca 17-21 (♂) or 20-24 mm (♀), width of midbody pro- and metazonae 1.0-1.2 and 2.8-3.8 (♂) or 1.5-1.8 and 3.0-4.0 mm (♀), respectively. Holotype 19 mm long, 1.0 and 2.8 mm wide on midbody pro- and metazonae, respectively. In width, head <collum <segment 2-4 <segment 5-16. Coloration (Figs 1H, 12, 14-15) varying from dark to light brownish; paraterga and posterior parts of metaterga finely yellow-brownish. Antennae long and slender, reaching back until posterior margin of segment 5 (♂) or segment 4 (♀) when stretched dorsally (Fig. 12 A–B).

Prozonae faintly microalveolate; metazonae rather microgranulate and shagreened. Collum (Figs 12B, 13B) with 4+4 (or 5+5) anterior and 2+2 (or 3+3) posterior setigerous spines. Metaterga 2-18 (Figs 12-13) each with 2+2 (or 3+3) anterior and 2+2 (or 3+3) posterior setigerous spines, lateral spine of posterior row being much larger than others; metatergum 19 with 3+3 anterior and 2+2 posterior, similar, small, setigerous tubercles. Paraterga very strongly developed, antler-shaped, usually three-branched, each tip with an evident lateral seta (Figs 12-13). Paraterga of collum stout, two-branched; paraterga 2-5 directed more dorsad than laterad; paraterga 19 directed cau dad, horizontal, lying level to dorsum; paraterga 6-18 directed obliquely upwards at ca 45°, in ♂ ending up clearly above dorsum (Figs 12-13), but paraterga slightly lower, shorter, subhorizontal and lying level to dorsum in ♀. Ozopores conspicuous, located at last incision of poriferous paraterga (Fig. 14A). Transverse sulcus obscure on collum and metaterga 2-4; more evident, but incomplete on metaterga 5-17 (Figs 12-13).

Sterna sparsely setose, cross-impressions very shallow (Figs 12-13). A paramedian pair of separated, short, rounded, poorly setose processes between ♂ coxae 4 (Fig. 14B). Legs long and slender, ca 2.5-2.8 (♂) or 2.0-2.2 (♀) times as long as body height; ♂ femora 5-7 each with a conspicuously densely pilose apophysis ventrally at about midlength (Figs 12C, 13 A–B, 14 C–E).

Gonopods (Fig. 14 F–G) very short. Coxite less than 1/3 as long as telopodite. Prefemur less than half the length of acropodite. Femorite stout, apically with a distinct sulcus. Solenophore quite complex and compact, divided into two well differentiated lobes, a higher, bipartite and apically acuminate lamina medialis, plus a lower and curved lamina lateralis; solenomere short and flagelliform.

Remark.

This obviously troglophilic species is rather eurytopic, occurring both outside and inside caves. It shows a remarkably variable pattern of spination on collum and metaterga (Figs 12-13), but the gonopod structure remains stable.