Stygohydracarus karanovici, Pesic, Vladimir M., 2001

Pesic, Vladimir M., 2001, Stygohydracarus karanovici sp. n., and Atractides inflatipes Lundblad, 1956, two water mites species (Acari: Hydrachnidia) from Montenegro (SE Europe), Zootaxa 17, pp. 1-7 : 4-7

Stygohydracarus karanovici sp. nov. ( Figs. 4­8 )

Material examined: Holotype, dissected and slide mounted in Hoyer's fluid; Yugoslavia, Crna Gora, lake Plavsko Jezero, interstitial waters, 18.02.1995, leg. Karanovic; Paratypes: 1 (in coll. Gerecke, Tübingen) and 1, same data as holotype dissected and slide mounted on Hoyer's fluid; one female, Skadar Lake, Malo Blato near Bobija, sublacustrin spring, 0 6.05.2000, leg. Pesic.

Description

Male (holotype, measurements of paratypes are given in parentheses): Idiosoma ( Fig. 2 ) length 325 (327), width 283 (280.5), lateral and caudal margins regularly rounded. Dorsal shield length 290 (274), width 264 (261), ratio length/width 1.1 (1.05). Idiosoma setae well developed, arranged as in Figure 4 .

Ocular pigment absent. Gnathosomal bay wide; coxal plate 1 anteriorly not remarkably protruding, their maximum width at level of anterior tip of coxal plate 2; medial suture lines of coxal plates 3 and 4 visible but weakly pronounced. Genital field ( Fig. 6 ): gonopore lengths 70 (69), anteriorly truncated, the posterior half straightened, with on each side 18 ­ 19 acetabula (15 ­ 15) placed in one or two rows on an elastic strip. Gnathosoma length 93.5, chelicera total length 99 (100). Palp measurements (L/H): P­ 1 20/23, P­ 2 56/41, P­3, 42/46, P­4 79/50; P­ 5 in a transverse position, not measurable. Morphology and setation of palp ( Fig. 5 ): P­2­3 with a very low number of fine, mostly short setae. P­4 with distally converging dorsal and ventral margins; ventral margin with a pit in its distal third, bearing a fine seta.

Female (in parentheses female from the Skadar Lake): Idiosoma length 388 (397), width 319 (347); dorsal shield length 339, width 286. Acetabula ­ bearing strips fused with ventral shield ( Fig. 8 ), gonopore length 122, number of genital acetabula on each side 16­ 18 (15­17). Mouthparts without sexual dimorphism, gnathosoma length 103; chelicera length 112, height 38; palp length/height: P­ 1 26/29, P­2 60/51, P­3 46/55, P­4 86/59. Morphology and setation of palp as in Figure 7 .

Discussion: The new species shares such important characters as the absence of ocular pigments and body measurements with Stygohydracarus troglobius K. Viets, 1932 . As compared with S. troglobius , S. karanovici n. sp. is characterized by the following features: idiosoma setae well developed, four setae inserted on each side of the gonopore; coxal plate 1 anteriorly not remarkably protruding; in both sexes acetabula on each side, 15­19 in male (10­13 in S. troglobius ), 15­18 in female (11­12 in S. troglobius ); ratio dorsal length P­4 /height 1.58 (1.79 in S. troglobius ) in male, 1.46 (1.77 in S. troglobius ) in female. The new species is similar to S. troglobius as described by Petrova (1966) (higher number of idiosomal setae, shape of suture lines and coxal plates). Stygohydracarus karanovici n. sp. differs from Petrova’s specimens by the shape of palp (if Petrova’s figures are correct, then P­4 is shorter than P­ 2 in Bulgarian specimen) and genital field (male gonopore straightened posteriorly). Smit et al. (2000) suggested that the species published by Petrova (1966) under the name Stygohydracarus troglobius document clearly that her material did not belong to this species (if her figures were correct) and that it probably represented an undescribed species.

Etymology: The species is named after its collector Dr. T. Karanovic (Perth).

Habitat: Stygohydracarus karanovici sp. nov. is a species characteristic of interstitial waters of lakes. The female we found in the locality Malo Blato (Skadar lake), together with mite species characteristic for stagnant waters ( Unionicola crassipes , U. minor , Brachypoda versicolar etc.), was thrown out from interstitial waters by sublacustrin spring (“Oko”) during heavy rains.

Distribution: Yugoslavia ( Crna Gora); only known from the interstitial waters of the Skadar lake and Plavsko Jezero­lake.

Figures

FIGURES 4 ­ 8. Stygohydracarus karanovici sp. nov., (4, 5, 6 = male; 7, 8 = female): 4 ­ ventral view; 5 ­ palp; 6 ­ genital field; 7 ­ palp; 8 ­ genital field. Scale bars = 100 µm.

FIGURES 1 ­ 3. Atractides inflatipes Lundblad, 1956, female: 1 – palp; 2 – I­L­ 5 / 6; 3 – genital field. Scale bar = 100 µm.