Africasia purpurea, Pešic & Smit, 2016

Pešic, V. & Smit, H., 2016, New records of water mites from Southeast Asia (Acari: Hydrachnidia) with the description of two new genera and 12 new species, Acarologia 56 (3), pp. 393-433 : 427-432

Africasia purpurea n. sp.

( Figures 22-23 )

Type series — Holotype female, dissected and slide mounted, Laos, 15-33-1 Kouangxi Waterfall , lentic bay within a pool behind a travertine barrier within the main brook, 19°44’55.9"N, 101°59’33.4"E, alt. ca. 490 m a.s.l., water depth 0.5 m, substrate: travertine mud covered by some leaves.

Diagnosis — (Male unknown). Dorsal colour pattern consisting of anterior and two posterolateral deep purple patches; Cx-IV with a short longitudinal ridge posterior to IV-L insertions; IV-L-4/5 each with one strong distal pennate seta.

Description — Female: Dorsal and ventral shields present; dorsal shield colour pattern as shown in Figure 23A (due to treatment with lactic acid in mounted specimens reddish); eye pigment well developed; ventral shield with steep lateral margins; tips of Cx-I extending beyond frontal margin; Cx-IV posterior to IV-L insertion with a longitudinal ridge; genital plates lightly defined, with numerous pairs of acetabula ( Figure 22B ); palp segments rotated, distal end of the uncate P-4 with a long antagonistic bristle ( Figures 22 C-D). Legs: number of swimming setae: II-L-4, 2; II-L-5, 2; III- L-4, 2; III-L-5, 5; IV-L-4, 2; IV-L-5, 2; IV-L-4/5 each with one dorsodistal pennate seta ( Figure 22F ).

Measurements — Dorsal shield L/W 356/327, ratio 1.09; ventral shield L/W 434/364; gnathosomal bay L 72; distance between most lateral pair of Ac 195, gonopore L/W 92/74, ratio 1.24. Palp total L 173, dL/H, dL/H ratio: P-1, 25/20, 1.27; P-2, 48/35, 1.38; P-3, 31/32, 0.95; P-4, 58/32, 1.85; P-5, 11/-; L P-2/P-4 ratio 0.82; gnathosoma vL 88; dL of I-L-2-6: 36, 34, 43, 63, 77; dL of IV-L: 65, 57, 50, 74, 86, 86.

Male: Unknown.

Etymology — The name refers to the characteristic colour of the new species.

Remarks — The characteristic colour pattern on the dorsal shield easily separates the new species from all other members of the genus. Other diagnostic features of the new species include Cx-IV with lateral ridges posterior to IV-L insertion, and the presence of one strong pennate seta on IV-L-4/5 each.

Distribution — Laos; only known from the locus typicus ( Figure 25A ).

Figures

FIGURE 22: Africasia purpurea n. sp., male, Kauangxi Waterfall, Laos: A – dorsal shield; B – ventral shield; C – gnathosoma and palp, medial view; D – palp, lateral view; E – I-L-2-6; F – IV-L. Scale bars – 100 µm.

FIGURE 23: Photoghraphs of Africasia purpurea n. sp., male, Kauangxi Waterfall, Laos: A – idiosoma, dorsal view (photographed before dissection); B – ventral shield; C-D – dorsal shield (specimen mounted in Hoyer’s medium).

FIGURE 25: Photoghraphs of sampling sites: A – Laos, Kauangxi Waterfall (locus typicus of Monatractides laosensis n. sp., Hexaxonopsis laosensis n. sp., Sinaxonopsis laosensis n. sp. and Africasia purpurea n. sp.); B – Laos, Kouangxi Waterfall, pond behind artifical barrier (sampling site of Hygrobates hamatus K. Viets, 1935, H. henni Wiles, 2004 and locus typicus of Forelia gereckei n. sp.); C – Vietnam, Bach MAE National Park, brook with a pool (sampling site of Monatarctides sp. and locus typicus of Limnesia scharfi n. sp., Schwoerbelia pioniformis n. sp. and Arrenurus contortus n. sp.; D – Cambodia, moat around the main Angkor temple (locus typicus of Hexaxonopsis