Africasia vietnamitica sp. nov.

(Figs. 8A–F, 9D–E)

Type series. Holotype female, dissected and slide mounted, Vietnam C20, DV 0 9, Ha Giang, Dong Van, Sang Tung, Dragon Cave, small lake - siphon in right arm, 23°12'41.8'' N, 105°14'12.9'' E, 1047 m asl., 04.ii.2010 Tomasin.

Diagnosis. Ocular pigment absent; dorsal shield without colour pattern; integument of dorsal shield with eight very lightly developed areas of radiating lines on inner surface; Cx-IV posterior to IV-L insertion without a longitudinal ridge; genital field with 70–75 pairs of acetabula on well-defined genital plates; III/IV-L-4/5 each with one short swimming seta.

Description. Female (male unknown)—Dorsal and ventral shields present; dorsal shield L 533, W 500, with eight very lightly developed areas of radiating lines on inner surface (two pairs laterally, one pair each anteriorly resp. posteriorly, see Fig. 9D); ventral shield L 569, W 538; tips of Cx-I ending posterior to frontal margin; genital field L 238, W 166, gonopore L/W 125/106, ratio 1.18, genital plates well defined, with 70–75 pairs of acetabula (Fig. 8B); palp (Figs. 8C–D) total L 216–223, L/H, L/H ratio: P-1, 32/31, 1.04; P-2, 60–62/45–46, 1.3–1.4; P-3, 39–40/42–43, 0.91–0.93; P-4, 66–70/34–38, 1.86–1.94; P-5, 19/8, 2.4; L P-2/P-4 ratio 0.88–0.91; palpal segments rotated, distal end of the uncate P-4 with one long, thin seta; gnathosoma vL 115; chelicera total L 112; dL of I–L-4–6 (Fig. 8E): 62, 77, 97; dL of IV–L: 75, 69, 71, 95, 110, 110; III/IV–L-4/5 each with one short swimming seta (Fig. 8F).

Etymology. Named after the country where the new species was detected.

Remarks. In addition to probable adaptations to the subterranean habitat (the absence of ocular pigment and of a colour pattern on the dorsal shield), the new species is characteristic in the presence of an increased number of acetabula located on well-defined acetabular plates, the Cx-IV without lateral ridges posterior to leg insertions, and presence of one short swimming seta on III–IV–L each. This species has no close relatives among recent congeners, but a decision about its eventual taxonomic status above species level can be made only when the presently unknown male of A. vietnamitica is described.

Distribution. Vietnam; only known from the locus typicus.