Glyphiulus scutatus Zhao & Liu, 2022

Zhao, Yi, Guo, Wan-Ru, Golovatch, Sergei I. & Liu, Wei-Xin, 2022, Revision of the javanicus species group of the millipede genus Glyphiulus Gervais, 1847, with descriptions of five new species from China (Diplopoda, Spirostreptida, Cambalopsidae), ZooKeys 1108, pp. 89-118 : 89

Glyphiulus scutatus Zhao & Liu sp. nov.

Figs 5B , 12 , 13

Type material.

Holotype ♂ (SCAU WL30), China, Guangxi Zhuang Autonomous Region, Hechi City, Du’an Yao Autonomous County, Napang Dong, 24°08'22"N, 107°51'07"E, 650 m alt., 2015-VII-26, leg. Chen Jujian, Wang Xinhui & Tang Mingruo. Paratypes: 2 ♂, 12 ♀ (SCAU WL30), same data as the holotype. 3 ♂, 4 ♀ (SCAU G72), same County, Cave Bianfu Dong, 24°01'55"N, 108°20'12"E, 550 m alt., 2017-VIII-18, leg. Tian Mingyi, Huang Sunbin, Wang Dianmei & Chen Mengzhen.

Etymology.

To emphasise the anterior gonopod showing a scalloped and shield-shaped coxosternum.

Diagnosis.

Differs from congeners of the Glyphiulus formosus -group by both ♂ femora 6 and 7 being slightly inflated and the anterior gonopod without apicomesal process, as well as the posterior gonopod with less than ten microspinules. Based on molecular evidence, G. scutatus Zhao & Liu, sp. nov. differs from all other Glyphiulus species analysed in a> 15.8% uncorrected p-distance of the COI barcoding gene.

Description.

Length of both sexes ca. 25.0-41.0 mm, mid-body rings round in cross-section, their width and height similar, 1.3-1.8 (♂) or 1.8-2.0 mm (♀). Body with 55-68 podous + 1-4 apodous rings + telson. Colouration purple-brownish to dark brownish, legs light brownish to almost transparent (Fig. 5B ).

Head surface smooth. Labrum with four teeth anteromedially (Fig. 13A ). Ocellaria blackish, with 8-12 ommatidia arranged in two irregular linear rows (Fig. 12B ). Antennae short, slightly clavate, reaching back to ring 3; in length, antennomeres 5> 3> 4> 2> 6> 1> 7. Antennomeres 5-7 each with a distodorsal field or corolla of bacilliform sensilla (sensory bacilli). Antennomere 7 with four sensory cones (Fig. 13B ). Gnathochilarium with a separate promentum, setae variable in number, polytrichous or smooth on promentum and mentum, lamellae linguales each with 4-6 setae (Fig. 13A ). Mandible not dissected.

Collum: crests complete and evident; carinotaxy formula I-III+P+M (Figs 11A, B ). Following metaterga strongly crested and extremely sharp; carinotaxy formula 2/2+I/i+3/3 (Fig. 12 ). Ozoporiferous tubercles very large, subcylindrical. Prozonae delicately alveolate-areolate, fine longitudinal striations in front of stricture. Metazonae with an obvious, corrugate, carved texture (Fig. 12 ). Rings 2 and 3 with long pleural flaps.

Epiproct simple, very narrow, caudal edge uneven, with a clear central tubercle dorsally (Fig. 12E ). Paraprocts regularly convex, each with several irregular rows of setae. Hypoproct transversely bean-shaped, with 3+3 small setae (Fig. 12F ).

Legs slender, about 1.1-1.3 times as long as mid-body height; claw with a small accessory spine at base, about ¼ as long as claw (Fig. 13H ). ♂ legs 1 very strongly reduced, represented by a sternum showing a pair of small, fused, paramedian, subunciform prongs directed forward, with 3+3 long setae at base; flanked by strongly separated, rudimentary, 2-segmented leg vestiges, with either a few or no setae (Fig. 13D ). ♂ legs 2 slightly hypertrophied, coxae large; penes small, much shorter than coxae, oblong-subtrapeziform, each with 1-4 strong setae distolaterally (Fig. 13F ). ♂ legs 3 modified through coxae being especially slender and elongate (Fig. 13C ). Both ♂ femora 6 and 7 slightly inflated.

Anterior gonopods (Fig. 13I ) with a scalloped and shield-shaped coxosternum with about 6-8 microsetae near lateral corner of coxite. Telopodite very large and coiled, 1-segmented, lateral in position, much higher than lateral corner of coxite, with a field of 5-7 microspinules at base and 4-5 strong setae apically.

Posterior gonopods (Figs 13G, J ) compact. Coxite subquadrate, with a field of about 8-10 basolateral microspinules in frontal view and with a field of ten median microspinules in caudal view; apical and mesal parts of coxite with dense, strong and curved setae. Lamelliform lobe membranous, with a short, broad, distally spike-like flagellum.

Vulvae very simple, bare, rather faintly emarginate medially (Fig. 13E ).

Remark.

In the absence of direct troglomorphic traits, this species can only be considered as troglophilic at most.

Figures

Figure 5. Pictures of live animals A G. sinuatoprocessus Zhao & Liu, sp. nov. from Cave Niubi Yan B G. scutatus Zhao & Liu, sp. nov. from Cave Bianfu Dong C G. portaliformis Zhao & Liu, sp. nov. from Cave Baiyan Dong D G. xiniudong Zhao & Liu, sp. nov. from Cave Xiniu Dong E G. conuliformis Zhao & Liu, sp. nov. from Cave Yanzi Dong.

Figure 11. Glyphiulus xiniudong Zhao & Liu, sp. nov., ♂ paratype A head and collum B gnathochilarium and left antenna C mid-body leg and claw D leg 1, frontal view E penes F ♀ paratype, vulvae G anterior gonopods, caudal view H, J posterior gonopod, frontal view I, K posterior gonopod, caudal view. Scale bars: 0.5 mm (A, B), 0.2 mm (C-I), 0.1 mm (J, K).

Figure 12. Glyphiulus scutatus Zhao & Liu, sp. nov., ♂ paratype from Cave Napang Dong A, B anterior body rings, dorsal and lateral views C, D mid-body rings, dorsal and lateral views, respectively E, F posterior body rings, dorsal and ventral views, respectively. Scale bars: 1 mm.

Figure 13. Glyphiulus scutatus Zhao & Liu, sp. nov., ♂ paratype from Cave Napang Dong A gnathochilarium and right antenna B antenna tip C leg 3, frontal view D leg 1, frontal view E ♀ paratype, vulvae F penes G, J posterior gonopod, frontal and caudal views, respectively H mid-body leg and claw I anterior gonopods, caudal view. Scale bars: 0.5 mm (A, H), 0.2 mm (B-E), 0.1 mm (F, G, I, J).