Lebertia (Mixolebertia) gibberipalpis Sokolow, 1948

Tuzovskij, Petr V., ., .., ., .,., .,., ., ., -, -, -, ..., -, L, -, -, P-, -, W & -, I-, 2023, On the the systematics of the water mite Lebertia gibberipalpis Sokolow, 1948 (Acari, Hydrachnidia, Lebertiidae), Ecologica Montenegrina 64, pp. 203-206 : 203-206

Lebertia (Mixolebertia) gibberipalpis Sokolow, 1948

( Figures 1-9 )

Material examined. Female , slide 9932, Asia , Kazakhstan, Turkestan Province , Tyulkubassky District , Aksu-Zhabagly Nature Reserve, Kshi-Kainda stream, 42°23'43.6"N 70°35'02.6"E, 1845 m a.s.l., depth 30-40 cm, bottom: large stones, mosses, 14.08.2019, leg. V. Stolbov .

Diagnosis. Both sexes. Integument lineated, medial length of coxal plates I longer than medial suture line of coxal plates II; P-2 strong expanded dorsally dorsal margin strongly curved, ventral margin weakly concave; P-3 with six long setae in three groups, each side by side: two dorsally in proximal portion, two distodorsally and two distoventrally; P-4 relatively short (L/H 2.6), P-2 and P-4 subequal in length, P-4 mediodistal peg-like seta very large; coxal plates II posterior margin narrow; legs without swimming setae, IV-Leg-6 with concave ventral margin.

Description. Female. Integument lineated ( Fig. 1 ). Setae Fch ( Fig. 2 ) longer and thicker than other idiosomal setae. Medial suture line of coxal plates I longer than medial suture line of coxal plates II (mL coxal plates I/coxal plates II ratio 1.27, Fig. 3 ). Coxal plates II with two narrow pointed apodemes directed posterolaterally, posterior margin narrow and straight. Coxal shield embracing the genital field for about 3/4 with acute posteromedial corners. Seta Pi and posteromedial corner of coxal plate IV well separated on each side. Genital field ( Fig. 5 ) with 23-25 medial and two posterolateral setae on each side, anterior acetabula longer than the two posterior acetabula; flaps elongate, L/W ratio 2.4. Excretory pore not sclerotized. Gnathosoma ( Fig. 6 ) with a short rostrum, ventral margin convex. Basal segment of chelicera large with equally convex dorsal margin, chela small, sickle-shaped (L basal segment/chela 5.0).

Pedipalp moderately long ( Fig. 4 ): P-1 short, with single dorsodistal setae; P-2 strongly expanded dorso-ventrally, the height larger than ventral margin length, with three short unequal dorsoproximal and two relatively long subequal dorsodistal setae, ventral margin concave, ventrodistal seta long, inserted a little distanced from ventrodistal segment edge; P-3 rather large with six long setae in three groups, each side by side: two proximdorsally, two distodorsally and two distoventrally; P-4 a little longer than P-3 (P-3/P-4 L ratio 0.95), proximal and distal margins of the segment nearly equal in height, ventral margin straight, ventral sectors 2:3:3, mediodistal peg-like seta very large and pointed, its length> than ½ the length of P-5, one fine dorsal seta placed near the centre of segment.

Legs without swimming setae, tarsi of first legs with subparallel dorsal and ventral margins ( Fig. 7 ). Fourth legs slender, IV-Leg-1 with one to two dorsodistal peg-like setae, IV-Leg-6 ventral margin concave, with five short, thin setae ( Fig. 8 ). Claws with short interior and long exterior clawlets, claw blade with slightly concave ventral margin ( Fig. 9 ).

Measurements (n=1). Idiosoma L about 1000; seta Fch L 125; coxal shield L 700; coxal plate I mL 175; coxal plate II mL 135, posterior margin W 62; distance between the insertions of IV-Legs 550; genital flap L 210, W 85; genital acetabula (ac-1-3) L/W: 87/37, 60/37, 50/42; gnathosomal bay L 200; genital bay L175; cheliceral segments L: base 240, chela 42; pedipalp segments (P–1–5) L/H, L/H ratio: 36/72, 0.5,120/102, 1.17, 115/72, 1.62, 123/48, 2.58, 30/18, 1.66, P-4 mediodistal peg-like seta: L/H 25/10; leg segments I-III L: I-Leg-1–6: 85, 110, 120, 175, 175, 160; II–Leg-1–6: 90, 125, 125, 185, 210, 200; III-Leg-1–6: 90, 160, 135, 225, 260, 220; IV–Leg-1–6 L/H, L/H ratio: 175/87, 2.0; 160/62, 2.6; 220/75, 2.9; 285/62, 4.6; 310/50, 6.2; 260/50, 5.25.

Remarks. The female Lebertia gibberipalpis is very similar to male except in the shape of the pregenital sclerite. The male differs in a smaller dimensions, genital field with numerous (>30) medial setae ( Sokolow 1948). This species is similar to L. longissima Sokolow, 1935 from Altai, L. noshaquensis Imamura, 1966 from Afghanistan, L. xuanensis Wang et al., 2020 from Central China, and L. altomontana Gerecke & Smit, 2022 from Nepal in the setation of third pedipalp segment (with six medial setae arranged in three groups, each side by side, two proximodorsally, two distodorsally, and two distoventrally). Lebertia gibberipalpis differs from these species by the following characters: P-2 strong expanded dorsoventrally, height of segment> than ventral margin length; P-4 with very large peg-like seta ( Fig. 4 ).

Habibitat. Running waters.

Distribution. Asia: Tadjikistan ( Sokolow 1948), Kazakhstan: Turkestan Province (present study).

Figures

Figures 1-4. Lebertia (Mixolebertia) gibberipalpis, female: 1 - fragment of dorsal surface; 2 - seta Fch; 3 - coxal plates and genital field; 4 - pedipalp; Scale bars: 1-2 = 100 μm, 3 = 200 μm, 4 = 50 μm.

Figures 5-9. Lebertia (Mixolebertia) gibberipalpis, female: 5 - genital field; 6 - gnathosoma and chelicera, lateral view; 7- I-Leg-4-6; 8 - IV-Leg-4-6; 9 - claw of leg IV. Scale bars: 5-7, 8 = 100 μm, 9 = 50 μm.