Stygotorrenticola coniseta sp. nov.

(Figs. 4A–E, 5A–G, 6A–B, 6A–D, 9A–B)

Type series. Holotype male, dissected and slide mounted, Vietnam CO4, QBTS 0 3, Ha Giang, Quan Ba, Tam Son, Grotta passante, 23º02'44.7''N, 104º59'23.9''E, 980 m asl., 29.i.2010, gours of dripping water – internal canyon, Tomasin. Paratypes: 2 males, one female (dorsal shield crushed) and one deutonymph, same data as holotype, one male, one female and one deutonymph dissected and slide mounted; one deutonymph, Vietnam CO6, WGS 84, Ha Giang, Quan Ba: near Tom Sai, Waste cave in village near the road, 23º04'53.9''N, 104º54'16.6''E, 985 m asl., 30.i.2010, Karaman-Chappuis in River bed, Tomasin.

Diagnosis. As for genus.

Description. Both sexes: After fixation, without remarkable colour patches. Idiosoma broadly rounded. Dorsal plate with traces of sutures indicating the fusion of shoulder plates. Distal edge of Cx-I flanking gnathosomal bay smooth, lacking any denticles or knob-shaped protrusions; Cxgl-4 well developed. Genital field elongated, with rounded anterior margin, lateral margins posteriorly slightly converging. P-2 ventral margin concave; P-3 anterior and posterior to ventral projection concave; P-4 ventral setae associated with short, pointed denticles.

Male (holotype, in parentheses some measurements of paratype)—Idiosoma (ventral view: Fig. 4C) L 442 (453), W 429 (375); dorsal shield (Figs. 4B, 9A–B) L 403 (403), W 311 (309), L/W ratio 1.3 (1.3); dorsal plate L (388); fused frontal platelets W 172 (172). Gnathosomal bay L 125 (132), Cx-I total L 209 (217), Cx-I mL 85 (85), ratio Cx-I L/Cx-I mL 2.5 (2.55). Genital field L/W 103 (108)/73 (74), ratio 1.40 (1.46); distance genital fieldexcretory pore 129 (126). Gnathosoma (Figs. 5C–D) vL 153 (155); chelicera (Fig. 5E) total L 197 (186), basal segment L 166 (154), claw L 44 (38), L basal segment/claw ratio 3.8 (4.1); palp (Figs. 5A–B) total L 299 (299), dL: P-1, 34 (35); P-2, 88 (85); P-3, 71 (72); P-4, 86 (86); P-5, 20 (21); P-2/P-4 ratio 1.02 (0.99). Legs: dL of I-L-4–6 (Fig. 5F): 78, 85, 89; I-L-6 H 29, I-L-6 L/H ratio 3.1.

Female—Ventral shield (Fig. 4D) L 484, W 402. Gnathosomal bay L 145, Cx-I total L 231, Cx-I mL 82, ratio Cx-I L/Cx-I mL 2.8. Genital field with subparallel lateral margins, L/W 142/92, ratio 1.54; distance genital fieldexcretory pore 109. Gnathosoma vL 160; palp (Fig. 4E) total L 321–326, dL: P-1, 37; P-2, 95; P-3, 77; P-4, 89–94; P-5, 23; P-2/P-4 ratio 1.01–1.07. Legs: dL of I-L-4–6: 83, 91, 95; I-L-6 H 31, I-L-6 L/H ratio 3.1; dL of IV-L-5–6: 135, 140.

Deutonymph—Idiosoma (ventral view: Fig. 6A) L 400, W 320; dorsally with a pair of small frontal platelets and a large dorsal plate (Fig. 6B), dorsal plate L/W 288/222, ratio 1.3. Coxal field: L 288, W 263, gnathosomal bay L 114. Provisional genital field with two pairs of acetabula, L/W 113/135, ratio 0.84. Gnathosoma vL 118; chelicera total L 156; palp: total L 223, dL: P-1, 25; P-2, 67; P-3, 49; P-4, 63; P-5, 19; P-2/P-4 ratio 1.06; palp without ventral setae on P-2 and P-3, P-4 ventral tubercles close to each other (Figs. 6C–D).

Etymology. The name of the new species refers to the conus-shaped ventral setae of P-2/-3.

Distribution. Vietnam.