Atractides (Atractides) ivanae, Pešić & Smit, 2021

Pešić, Vladimir & Smit, Harry, 2021, Water mites of the genus Atractides Koch, 1837 from Kyrgyzstan (Acari: Hydrachnidia: Hygrobatidae) with the description of six new species, Acarologia 61 (2), pp. 332-355 : 347-350

Atractides (Atractides) ivanae n. sp.

Zoobank: EB704886-6D27-4A4B-965A-16679CEF8999

Figures 11-12

Type material — Kyrgyzstan: Holotype ♂, dissected and slide mounted ( RMNH), KR27 river along the road to Son Kol Lake , 41°56.487 ′ N, 75°35.272 ′ E, 2428 m a.s.l., 15 Aug. 2013,

leg. Pešić & Smit; 1♀, KR14 Karakal region, road to May Saz pass, stream, 42°25.033 ′ N, 79°02.657 ′ E, 3348 m a.s.l., 12 Aug. 2013, leg. Pešić & Smit, dissected and slide mounted ( RMNH); KR15 Karakal region, road to May Saz pass, fast flowing river, 42°25.004 ′ N,

78°58.100 ′ E, 2981 m a.s.l., 12 Aug. 2013, leg. Pešić & Smit, 2♀.

Diagnosis — Integument striated; genital field with acetabula in a weakly curved line,

Ac subtriangular in shape; excretory pore smooth; Vgl-1 not fused to Vgl-2; seta S-1 bluntly pointed, not apically truncated; I-L-6 stout (L/H <5.0 in ♂, <6.0 in ♀) and relatively short, L I-L-5/6 ratio 1.5-1.9. Males: P-2 and P-3 ventrally each with a distinct protrusion; P-4 ventral setae very long, exceeding length of the segment. Genital plate anterior margin slightly convex or straight, not indented, Ac-3 subtriangular, not elongated. Female: P-3 without central thickening of its ventral margin.

Description — General features — Integument striated, muscle insertions unsclerotized; mediocaudal margin Cx-I convex, apodemes of Cx-II in in an acute angle with the median line; posterior margin of Cx-IV with short posterior extension ( Figure 11A ). Ac in an weakly curved line, subtriangular in shape. Excretory pore smooth; Vgl-1 not fused to Vgl-2. Palp with strong sexual dimorphism, P-4 sword seta near distoventral hair. I-L-5 setae S-1 and S-2 distally narrowed, bluntly pointed, S-1 longish, S-2 proximally enlarged, distance S-1-2 short; I-L-6 stout, slightly curved, proximally thickened ( Figure 12 C-D). Male — Genital plate anterior margin slightly convex or straight, posterior margin indented ( Figure 11A ); P-2 and P-3 each with a strong lamellar ventral extension, P-4 slightly protruding near proximoventral seta, ventral setae very long, exceeding the length of the segment ( Figure 12A ). Female — P-2 without projection, ventral margin slightly protruding distally, P-3/4 nearly straight ( Figure 12B ).

Measurements. Male (holotype) — Idiosoma L 697, W 494; maximum diameter Dgl-4, 23. Coxal shield L 353; Cx-III W 413; Cx-I+II mL 125, Cx-I+II lL 266. Genital field L/W 123/145, ratio 0.85, L Ac-1-3: 43-45, 47-50, 42. Ejaculatory complex ( Figure 11B ) L 139.

Gnathosoma — Palp total L 335; dL/H, dL/H ratio: P-1, 38/34; 1.1; P-2, 71/58, 1.23; P-3,

80/48, 1.65; P-4, 110/41, 2.7; P-5, 36/16, 2.3; length ratio P-2/P-4 0.65. Gnathosoma vL 134;

chelicera total L 259.

Legs — I-L-5 dL 225, vL 169, dL/vL ratio 1.33, maximum H 59, dL/maximum H 3.8, S-1

L 77, L/W ratio 7.0, S-2 L 70, L/W ratio 5.6, distance S-1-2, 14, dL ratio S-1/2 1.1; I-L-6 dL

119, central H 28, dL/central H ratio 4.2; L I-L-5/6 ratio 1.89.

Female (specimen from KR14, n = 1) — Idiosoma L 481, W 318; maximum diameter Dgl-4, 32. Coxal shield L 331; Cx-III W 359; Cx-I+II mL 95, Cx-I+II lL 203. Genital field

L/W 178/172, genital plates L 114-116, pregenital sclerite W 109, gonopore L 148, L Ac-1-3:

40-41, 38-39, 34-36. Egg maximum diameter (n =1) 184.

Gnathosoma — Palp total L 348; dL/H, dL/H ratio: P-1, 34/28, 1.2; P-2, 75/49, 1.52; P-3,

92/39, 2.35; P-4, 109/30, 3.7; P-5, 38/16, 2.4; length ratio P-2/P-4 0.69. Gnathosoma vL 123;

chelicera total L 180.

Legs — I-L-5 dL 187, vL 139, dL/vL ratio 1.34, maximum H 52, dL/maximum H 3.6, S-1

L 80, L/W ratio 7.8, S-2 L 80, L/W ratio 5.7, distance S-1-2, 11, dL ratio S-1/2 1.0; I-L-6 dL

122, central H 22, dL/central H ratio 5.6; L I-L-5/6 ratio 1.53.

Etymology — The new species is named after Ivana Pozojević (Zagreb, Croatia) in appreciation of her work on water mites.

Discussion — The presence of a strong ventral protrusion on P- 3 in males, makes the new species similar to A. gibberipalpis Piersig, 1898 , A. inflatus (Walter, 1925) and A. yunusi n. sp.

(see below). Atractides gibberipalpis , a rhitrobiontic species from the Palaearctic ( Sokolow

1940, Gerecke 2003, Pešić et al. 2004, Pešić and Erman 2006) differs from both new species from Kyrgyzstan in the shape of male genital plate (Ac larger, Ac-3 elongated, drop-shaped, anterior margin more or less indented; see Figure 13D ). Atractides inflatus differs in having lineated integument, in the both sexes I-L-6 relatively long, L I-L-5/6 ratio 1.3-1.4, in male the protrusions of P-2 and -3 more laterally flattened, and in female the both P-2 and P-3 with a gentle central thickening covered by fine denticulation ( Gerecke 2003). For similarities and differences in comparison with Atractides yunusi , see below in discussion of the latter species.

Distribution — Kyrgyzstan ; know from the high-order streams in Tien Shan mountains at an elevation from 2,400 to 3,400 meters.

Figures

Figure 11 Atractides ivanaen. sp. (A-B, ♂ holotype, KR27 stream on road to Son Kul; C, ♀ KR14 stream on road to May Saz, Kyrgyzstan). A – idiosoma, ventral view; B – photograph of ejaculatory complex; C – genital field. Scale bar = 100 µm.

Figure 12 Atractides ivanaen. sp. (A, C, ♂ holotype, KR27 stream on road to Son Kul; B, D, ♀ KR14 stream on road to May Saz, Kyrgyzstan). A-B – palp, medial view; C-D – I-L-5 and -6. Scale bar = 100 µm.

Figure 13 A-E Atractides yunusin. sp., ♂ holotype, KR15 river on road to May Saz, Kyrgyzstan. A – coxal field, partial view; B – genital field; C – photograph of ejaculatory complex; D – I-L-5 and -6; E – palp, medial view. FAtractides gibberipalpis, ♂, Mrtvica river, Montenegro: genital field. Scale bars = 100 µm.