Hexaxonopsis laosensis, 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 : 414

Hexaxonopsis laosensis n. sp.

( Figures 13-14 , 15 A-B)

Type material — Holotype male, dissected and slide mounted, Laos, 15-33-1, Kouangxi Waterfall , lentic bay within a pond 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 . Paratypes: 4/5/0, same data as holotype, one female dissected and slide mounted .

Diagnosis — Dorsal shield colour pattern consisting of a light-reddish elongated central patch; lateral margins posterior to IV-L insertions with developed triangular projection on each side of ventral shield.

Description — Dorsal and ventral shields anteriorly lightly fused; dorsal shield with seven pairs of glandularia (the seventh pair inconspicuous, flanking the excretory pore); postocularia well distanced from anterior margin; excretory pore projecting, located at the posterior end of dorsal shield; anterior portion of dorsal shield with 14-15 pairs of triangular, posteriorly-directed (hyaline?) denticles ( Figures 13A , 14A ); dorsal shield colour as shown in Figures 15 A-B; eye pigment well developed. Ventral shield oval, slightly truncate at anterior end, lateral margins rounded, with well developed triangular projection on each side ( Figures 13B , 14B ), posterior to the insertions of IV-L. Lateral margins of Cx-I/II with 1-3 strong, hook-like, posteriorly-directed projections; two pairs of glandularia in region between genital field and opening for insertion of IV-L, these relatively close together; a relatively long longitudinal ridge posterior to IV-L insertions. Genital field with three pairs of Ac, arranged in an arc. Palp: ventral margin of P-2 convex, distal margin of P- 3 with well developed hyaline extensions, ventral margin of P-4 convexly protruding in the centre, here with two seta (one long and heavy, another long and slender) on small elevated ridges ( Figures 13 C-D,14C). Legs: number of swimming setae: II-

Figures

FIGURE 13: Hexaxonopsis (Hexaxonopsis) laosensis n. sp., male, Kauangxi Waterfall, Laos: A – dorsal shield; B – ventral shield (arrow showing the projection on the lateral margin of the ventral shield); C-D – palp; E – gnathosoma; F – ejaculatory complex; G – I-L. Scale bars – 100 µm.

FIGURE 14: Hexaxonopsis (Hexaxonopsis) laosensis n. sp., female, Kauangxi Waterfall, Laos: A – dorsal shield; B – ventral shield; C – palp. Scale bars – 100 µm.

FIGURE 15: Photoghraphs of dorsal shield. A-B Hexaxonopsis laosensis n. sp.: A – male holotype; B – female paratype. C-D H. cambodiensis n. sp.: A – male holotype; B – female paratype. E – H. angkoriensis n. sp., female holotype.