Hyleoglomeris variabilis, Liu, Weixin & Tian, Mingyi, 2015

Liu, Weixin & Tian, Mingyi, 2015, A checklist of millipede genus Hyleoglomeris Verhoeff, 1910 in mainland China, with descriptions of seven new species (Diplopoda, Glomerida, Glomeridae), Zootaxa 4032 (1), pp. 103-116 : 110-112

Hyleoglomeris variabilis sp. n.

Figs. 7 , 8A & 9–10 .

Material examined: Holotype male ( SCAU), China, Guizhou, Qiandongnan Zizhizhou, Cengong County, Pingzhuang Town, Cave Wanfuchangcheng Dong, 27°24’50.91’’N, 108°35’43.0’’E, 830 m, 29.VI.2014, leg. Tian Mingyi, Liu Weixin, Yin Haomin, Huang Sunbin, Wang Xinhui. Paratypes. 1 male, 1 female ( IZAS), 1 male, 1 female ( ZMUM ρ2650), 6 males, 6 females ( SCAU), same locality, together with holotype.

Etymology. The name of this species refers to the telopod tibia which is supplied with a variably shaped caudomedial process; adjective.

Diagnosis. Using the available key to the Hyleoglomeris species of continental China ( Golovatch et al. 2006, 2012), this new species is unique in showing four transverse striae on the collum ( Fig. 8A ), occasionally one of these being incomplete, while the male telopodite 17 is 4- or 5-segmented, combined with a highly variable caudomedial process on the telopod tibia.

Description. Length of both sexes ca 3.5–6.0 mm, width 2.5–4.0 mm. Coloration of most samples entirely pallid, but four of these light yellow-brown ( Fig. 7 ). Head grey-brown, antennae yellow-brown; antennomere 6 ca 1.8–2.2 times as long as wide ( Fig. 9 A). Ocelli at least 2+1, translucent, barely visible. Tömösváry’s organ transverse-oval, only slightly wider than long. Collum darker, with a central, oval, marbled light brownish spot ( Figs. 7 A–B). Both sides of following terga darker, light brown; other parts light yellow. Caudal and lateral margins of all terga translucent ( Figs. 7 B–C).

Collum with four transverse striae ( Fig. 8A ), occassionally one of these incomplete. Thoracic shield with a narrow hyposchism, the latter not reaching behind caudal tergal margin ( Fig. 11 B); 8–9 transverse striae, 4(5) starting below, one level to, 4(3) above schism, 4–6 striae (never the last from below) crossing the dorsum. Male pygidium sometimes slightly concave medially at caudal margin.

Male leg 1 ( Fig. 9 B) with a small caudomedial cone on coxa, the latter with two spines on top; claw unusually prominent.

Male leg 2 ( Fig. 9 C) with a small caudomedial gonopore on a small rounded coxa, without a gonapophysis; claw unusually prominent.

Male leg 17 ( Fig. 10 A) with a low and rather irregularly shaped outer coxal lobe; telopodite 4-segmented, sometimes 5-segmented, tarsus with two subapical spine.

Male leg 18 ( Fig. 10 B) with a very narrowly arch-shaped syncoxital notch; telopodite 4-segmented.

Telopods ( Fig. 10 C) with a high, rounded, linguiform, sparsely setose, central syncoxital lobe flanked by two setose horns, each latter crowned with a small lobe and a pointed tip ( Fig. 10 D). Prefemur faintly micropapillate laterally, with a well-developed frontomedial trichostele. Femur with a smaller frontomedial trichostele. Caudomedial femoral process prominent, tip with a membranous sac, subapically with an evident lobe on caudal face. Tibia with a strong distomedial seta, caudomedial process rather variable, occasionally conspicuous, rounded, apically with a small lobe, sometimes not particularly evident; a distinct, papillate tubercle at base on caudal face. Tarsus rather strongly sigmoid, narrowly subacuminate apically.

Remark. Although a few samples of this species have retained a faint pigment in the tegument, it seems to be a troglobite.

Figures

FIGURE 7. Hyleoglomeris variabilis sp. n., male paratype. A – C. body, ventral, lateral and dorsal view, respectively. Photographed not to scale.

FIGURE 9. Hyleoglomeris variabilis sp. n., male paratype. A. antenna, front view. B. leg 1, front view. C. leg 2, caudal view. Scale bar: 0.5 mm.

FIGURE 10. Hyleoglomeris variabilis sp. n., male paratype. A. leg 17, front view. B. leg 18, front view. C. right half of telopods, front view. D. tip of syncoxital horn, front view. Scale bar: 0.5 mm.

FIGURE 11. Hyleoglomeris multistriata sp. n., male paratype. A – C. body, ventral, lateral and dorsal view, respectively. Photographed not to scale.

FIGURE 8. A. collum of Hyleoglomeris variablis sp. n., male paratype. B. collum of Hyleoglomeris multistriata sp. n., male paratype. Scale bar: 0.5 mm.