Atractides nikooae Pesic

Pesic, Vladimir, Saboori, Alireza, Asadi, Mahdieh & Vafaei, Reza, 2004, Studies on water mites of the family Hygrobatidae (Acari, Hydrachnidia) from Iran, I. The water mite genus Atractides Koch, with the description of five new species, Zootaxa 495, pp. 1-40 : 22-24

Atractides nikooae Pesic sp. nov.

( Figs. 34–40 )

Type material: Holotype: male, dissected and mounted in Hoyer's fluid; Iran: IR60 Markazi Province, Ghareh Chai stream 30 km after Tafresh city (90 km N Arak), 24.08.2003, leg. Pesic. Paratypes: 7 females, same data as holotype, one of these females dissected and mounted on Hoyer's fluid.

Diagnosis: dorsal integument: striated; muscle attachments: unsclerotized. I­L: I­L­5 S­1­2 distanced, S­1 slender, blunt, S­2 basally thickened, more pointed; I­L­6 slender, curved, with maximum H proximally. Genital field: Ac small, in a curved line; excretory pore: smooth; Vgl­1: not fused to Vgl­2. Palp: no sexual dimorphism, ventral margin P­2 straight, with slightly curved distal edge, P­3 straight, ventral margin of P­4 divided by hair insertions in sections 1:1:2, sword seta near the distoventral hair.

Description

Male: Length of idiosoma 514, width 357. Dorsally the integument is striated; muscle attachments: unsclerotized. Coxal field ( Fig. 34 ): mediocaudal margin of Cx­1+2 with a large, slightly concave area between the laterally directed apodemes of Cx­2 ( Fig. 34 ); length between anterior end of first coxae and posterior end of fourth coxae 339; Cx­3 width 385, Cx­1+2 width 304; Cx­1+2 medial suture 100 in length; distance from lateralmost tips of Cx­2 to the medioposterior edge of Cx­1+2 212. Measurements of mouthparts: cheliceral claw 56 in length; palp total length 318, dorsal length/height and relative length (% total length, in parentheses) of single segments: P­ 1 31/29 (9.7), P­2 71/54 (22.3), P­3 75/46 (23.6), P­4 104/39 (32.7), P­ 5 37/12 (11.6); length ratio P­2/P­4 is 0.68; palp ( Fig. 36 ): ventral margin P­2 straight, with slightly curved distal edge, P­3 straight, P­ 4 1:1:2, sword seta near the distoventral hair. Genital field ( Fig. 35 ): apple­shaped with nearly straight, irregular anterior margin; 94 in length, 96 in width, Ac­1­3 length 21­23­ 27; excretory pore smooth; Vgl­1: separated from Vgl­2

I­L ( Fig. 37 ): S­1/2heteromorphic and distanced, S­1 long, S­2 shortened, enlarged; I­ L­6 long and slender; I­L­5 dorsal length 196, I­L­5 ventral length 115, ratio dorsal length I­L­5 /ventral length 1.7, I­L­5 central height 50, ratio dorsal length I­L­5/central height 3.92, S­1 length 100, ratio length S­1/width 11.6, S­2 length 71, ratio length S­2/ width 6.2, distance between sword setae of I­L­5 30; ratio length S­1/2 1.41; I­L­6 length 152, I­ L­6 central height 18, ratio length I­L­6/central height 8.3; ratio length I­L­5/6 1.23.

Female: Length of idiosoma 892, width 650. Dorsally the integument is striated; muscle attachments: unsclerotized. Coxal field: mediocaudal margin of Cx­1+2 with a large, slightly concave area between the laterally directed apodemes of Cx­2; length between anterior end of first coxae and posterior end of fourth coxae 400, Cx­3 width 511, Cx­1+2 width 365 Cx­1+2 medial suture 135 in length; distance from lateralmost tips of Cx­2 to the medioposterior edge of Cx­1+2 260. Measurements of mouthparts: chelicera 250 in length, claw 75 in length; palp total length 408, dorsal length/height and relative length (% total length, in parentheses) of single segments: P­1 40/40 (9.8), P­2 91/69 (22.3), P­3 112/ 52 (27.5), P­4 125/34 (30.6), P­ 5 40/15 (9.8); length ratio P­2/P­4 is 0.73; palp ( Fig. 39 ): ventral margin P­2 straight, with slightly curved distal edge, P­4 more slender than in male, 1:1:2, sword seta near the distoventral hair. Genital field ( Fig. 40 ): Ac in a curved line, genital plates with weak indentations at borders Ac­1/2 and Ac­2/3; 160 in length, 177 in width, Ac­1­3 length 25­29­36; excretory pore smooth; Vgl­1: separated from Vgl­ 2.

I­L ( Fig. 38 ): I­L­5 both S­1/2 not enlarged distally, S­2 strongly thickened in the basal third part, distance S­1­2 large (> 50 µm); I­L­6 curved, maximum H basally, strongly narrowed in the centre (HB); I­L­5 dorsal length 252, I­L­5 ventral length 135, ratio dorsal length I­L­5 /ventral length 1.89, I­L­5 central height 77, ratio dorsal length I­L­5/central height 3.3, S­1 length 125, ratio length S­1/width 10.2, S­2 length 83, ratio length S­2/ width 4.4, distance between sword setae of I­L­5 57; ratio length S­1/2 1.5; I­L­6 length 198, I­L­6 central height 19, ratio length I­L­6/central height 10.3; ratio length I­L­5/6 1.27.

Discussion: Among the species with relatively small Ac, excretory pore smooth, I­L­ 5/6 slender, A. nikooae sp. nov. is most similar to A. diastema ( Szalay, 1935) , A. algeriensis ( Lundblad, 1942) , and A. cultellatus ( K.Viets, 1930) due to absence of muscle attachment sclerites, striated integument and the Vgl­1 not fused to Vgl­2. From the latter two species, A. nikooae sp. nov. is easily distinguished by the larger distance S­1­2, while the ventral margin of P­2 is straight, not distally protruding. Furthermore, from A. cultellatus , a species known only in the female sex, A. nikooae sp. nov. differs, in a longer median suture Cx­1+2 (in A. cultellatus L = 90 µm) and the sword seta on P­4 not particularly thickened.

A. nikooae sp. nov. differs from A. diastema (in parentheses data from Gerecke 2003), a weakly defined species from Hungary and Poland known only in the female sex, by the following features: the genital plates are not elongated, ventral margin of P­2 is straight (ventral marginof P­2 slightly protruding), ventral margin of P­4 divided by hair insertions in sections 1:1:2 (2:2: 1 in A. diastema ), more slender palp segments (L/H P­3 2.77, P­4 4.20), and a more heteromorphic setae S­1/2 (L S­1/2 1.3).

Etymology: The species is named after Nikoo Saboori, a daughter of the second author (A.S).

Biology: Atractides nikooae sp. nov. is very likely a rhitrobiontic species.

Distribution: Iran, only known from the locus typicus in the Markazi Province.

Figures

FIGURES 34 – 37. Atractides nikooae sp. nov., male: 34 = idiosoma, ventral view; 35 = genital field; 36 = palp; 37 = I­L­ 5 / 6. Scale bars = 0.1 mm.

FIGURES 38 – 40. Atractides nikooae sp. nov., female: 38 = I­L­ 5 / 6; 39 = palp; 40 = genital field. Scale bars = 0.1 mm.