Lebertia (Lebertia) himalayaensis, Gerecke & Smit, 2022

Gerecke, Reinhard & Smit, Harry, 2022, Water mites of the genusLebertia Neuman, 1880 from the eastern Himalayas (Acari: Hydrachnidia: Lebertiidae), Acarologia 62 (2), pp. 302-316 : 303-305

Lebertia (Lebertia) himalayaensis n. sp.

Zoobank: 0CD2F98A-2373-4871-97DF-FF4DFFACFA71

( Figures 1 A-E, 6A)

Type series — Holotype ♂, Bhutan 03, Dumcho , Haa river, pool 3 ( Figure 6A ), 27°21.883′

N, 89°17.738′ E, 2675 m a.s.l., 07 Aug. 2016, leg. W. Klein, slide mounted ( NBC). Paratype

♀, Nepal 03, stream at Jorsalle, 27°46.998′ N, 86°43.062′ E, alt 3101 m, 10 Apr. 2016 leg P.W.

Veel, slide mounted ( NBC).

Other material examined – Nepal 03, 1 dn slide mounted.

Diagnosis — Integument smooth or with a fine striation; small in dimensions (total L genital field ♂ 123, ♀ 130; total L palp ♂ 234, ♀ 227; L IV-L-4-6, 145; 155-165; 150-155);

legs without swimming setae; P-3 mediodistal seta close to dorsodistal seta (A/B 3.4-3.6); P-4 maximum H in distal part, insertions of setae dividing ventral margin into short proximal and distal, and a large central sector(s) (21-24/47-52/28-29 %).

Description — Integument thin and smooth, a fine striation locally visible. Cx-I/-II nearly equal in medial L (ratio 0.9-1.1), posterior margin rather wide (33). Glandularia V3 and setae

V1 not fused to coxal shield, V-3 far away from posterolateral margin Cx-IV ( Figure 1A ). Proportions and setation of distal segments of fourth leg as in Figure 1D ; IV-L-6 slightly bowed, with 2-3 fine and short ventral setae; IV-L claw L 35-40. Genital field ( Figure 1E ) with lateral margins of genital flaps strongly diverging from anterior to posterior end, medial setae (♂: 20, ♀: 9) in a single row. Excretory pore smooth. Gnathosoma with an equally rounded ventral margin ( Figure 1B ). P-2 relatively slender (L/H 1.49-1.57), ventral seta basally strong, slightly shorter than L of segment ( Figure 1C ); P-3 rather slender, in basal part not strongly narrowed, dorsal and ventral margin equally diverging from base to tip, with 5 medial setae (2 side by side dorsocentrally, medio-and dorsodistal setae close to each other near distal edge, distoventral seta near segment edge); P-4 club shaped, with dorsal and ventral margins distinctly diverging from base to distal quarter, mediodistal peg seta strong, pointed, ventral setae separated by a wide gap (nearly 50 % segment L), proximoventral setae near proximal, distoventral seta near distal segment end. Measurements: see Table 1.

Etymology — Named for its occurrence in the Himalayas.

Discussion — Lebertia himalayaensis n. sp. differs from many Asian Lebertia s. str. species in the complete absence of swimming setae. Among the four species with the same diagnostic character state, only L. sutschanica Sokolow, 1934 agrees in a smooth integument, for the other three, an integument sculpturation is reported: L. acuta Sokolow, 1934 (reticulation),

L. cylindrica Wang & Guo, 2016 and L. pseudomaglioi Wang et al., 2020 (long, resp. short lines). All these species are distinctly major in dimensions (e.g., coxal shield L> 500, genital flap L> 150, P-4 L> 100), and none of these has the ventral setae on P-4 as widely separated as L. himalayaensis n. sp. Among the species known from Europe ( Gerecke 2009), in the combination of a smooth integument, legs without swimming setae and a clavate P-4, L.

himalayaensis n. sp. is most similar to L. castalia K. Viets, 1925 . This species differs from L. himalayaensis n. sp. in the position of P-4 ventral setae (closer to each other, proportions of ventral sectors 2:3:2) and general major dimensions (e.g., palp total L> 320, IV-L-4-6

L> 180). Lebertia fimbriata Thor, 1899 a further European species combining a smooth integument and clavate P-4, differs in the presence of two long distal swimming setae at the penultimate segments of III-L and IV-L. New molecular data indicate that this taxon represents a species group with several so far cryptic species in Europe (unpubl. data). As to judge from the published figures and data, a male from China recently attributed to this species ( Wang et al. 2016) is similar to L. fimbriata in shape of idiosoma and palp, but differs from European specimens in proportions and setation of IV-L (stouter, L/H IV-L-4-6, 4.2, 4.7, 4.6, IV-L-5).

Thus, it is obviously a representative of a different species.

Figures

Figure 1 Lebertia(Lebertia) himalayaensisn. sp., type series. A-D, ♂; A – venter; B – gnathosoma with left palp and chelicera in situ; C – right palp medial; D – IV-L-3-6; E – ♀ genital field. Scale bars: 100 µm.

Figure 6 Collection sites. A – Haa River (Bhutan 03); B – Sertu Khola, Nunthala (Nepal 06); C – Garden stream, Nunthala (Nepal 05); D – Surke Khola (Nepal 04); E – stream S of Gokyo (Nepal 01); F – stream Dudh Kosi Nadi (Nepal 02). Authors: W. Klein (A), P.V. Veel (B-F).