Hyleoglomeris cavicola, Likhitrakarn, Natdanai, Golovatch, Sergei I. & Panha, Somsak, 2015

Likhitrakarn, Natdanai, Golovatch, Sergei I. & Panha, Somsak, 2015, Three new species of the pill millipede genus Hyleoglomeris Verhoeff, 1910, from northern Thailand (Diplopoda, Glomerida, Glomeridae), Zootaxa 4044 (1), pp. 130-140 : 135-137

Hyleoglomeris cavicola sp. n.

Figs 3 D–F & 5.

Holotype male ( CUMZ), Thailand, Chiang Mai Province, Chom Thong District, Cave Barijainda, 417 m a.s.l., 18°29'57"N 98°40'19"E, 13/10/2009, leg. N. Likhitrakarn, H. Enghoff, C. Sutcharit and S. Panha.

Paratypes. 13 males, 39 females ( CUMZ), 2 males, 2 females ( ZMUC), 2 males, 2 females ( ZMUM ƿ2714), 2 males, 2 females ( NHMW), same locality, together with holotype.

Name. ‘Cavicola’, a compound Latin noun, derived from ‘caverna’ meaning cave, ending in ‘-cola’ meaning inhabitant. The specific epithet refers to the habitat where this new species occurs.

Diagnosis. Differs in the unusual, strongly contrasting colour pattern, in which the head, antennae and collum are brown, while the following terga each with a pair of large, paramedian, dark triangles at their caudal margins and an evident light brown to dark axial stripe.

Description. Length of non-stretched, but unrolled specimens ca 7.2–8.9 mm (males), 7.4–11.2 mm (females), width 3.4–4.5 (males), 3.8–5.4 mm (females).

Coloration very vivid, colour pattern strongly contrasting ( Fig. 3 D–F); background light yellowish to pallid. Collum light to dark brown. Thoracic shield with a small, paramedian, dark triangle at caudal margin. Terga 3–11 each with a contrasting pair of large, paramedian, dark triangles at caudal margin and an evident light brown to dark axial stripe. Lateral sides of these terga also with a pair of small, sublateral, dark to marbled light brownish spots beside the triangles ( Fig. 3 D & E). Pygidium with as pair of large, paramedian, dark, inverted triangles at dorsal margin. Antenna and distal podomeres rusty brown to blackish. Ocelli blackish. Labrum and venter light yellowish to pallid.

Labrum sparsely setose. Gnathochilarium with 2+2 palps of subequal length. Ocellaria blackish, ocelli 8(7)+1, cornea very convex, translucent. Antennae with four evident apical cones, segment 6 ca 1.9–2.2 times as long as high. Organ of Tömösváry oblong-oval, elongate, ca 1.3–1.5 times as long as broad.

Collum as usual, with two transverse striae. Thoracic shield with a small hyposchism field not projecting caudad behind tergal margin. Striae 7–8, mostly superficial, only lower 2–3 lying above schism, one level to schism, remaining 4–5 below schism, with 3–4 complete, crossing the dorsum. Terga 3 and 4 broadly rounded laterally. Following terga in front of pygidium rather clearly concave medially at caudal edge and with two striae starting above lateral edge. Male pygidium clearly concave medially at caudal edge.

Male legs 17 ( Fig. 5 A & B) particularly strongly reduced, with a rather low to medium-sized, often irregularly rounded coxal lobe and a 4-segmented telopodite. Male legs 18 ( Fig. 5 C) less strongly reduced, with a more or less narrowly ogival syncoxital notch and a 4-segmented telopodite; femur with a small, setose, caudomedial tubercle (k) near apex.

Telopods ( Fig. 5 D–F) as usual, strongly incrassate, with a high, subquadrate, roundly emarginated syncoxital lobe flanked by two setose horns, each latter crowned by a subapical setoid filament ( Fig. 5 F). Prefemur micropapillate laterally ( Fig. 5 D & E). Caudomedial femoral process prominent, subapically with a rounded subtriangular lobe on caudal face, modest granulations at base ( Fig. 5 E & E). Caudomedial process of tibia evident, directed mesad. Tarsus rather moderately sigmoid, narrowly rounded apically, with a strong terminal seta.

Remarks. This species was found inside Cave Barijainda and in the surrounding dry dipterocarp forest. This large cave in Doi Inthanon Mountain is located near the Mae Klang River.

Figures

FIGURE 3. Hyleoglomeris aurea sp. n., (A – C) male holotype; Hyleoglomeris cavicola sp. n., (D – F), D male paratype, E & F male holotype, habitus in dorsal, ventral, lateral, dorsal, dorsal and ventral views, respectively. Scale bar: 0.2 mm.

FIGURE 5. Hyleoglomeris cavicola sp. n., (A & C – F) male holotype, (B) male paratype. A & B leg 17 C leg 18 D & E telopod, front and caudal views, respectively. F tip of syncoxital horn. Scale bar: A – E 0.2 mm; F drawn not to scale.