Rutripalpus limicola Sokolow, 1934

Gerecke, Reinhard & Tuzovskij, Petr, 2001, The water mite Rutripalpus limicola Sokolow, 1934: new data on morphology and biology, and considerations on the systematic position of the monotypic family Rutripalpidae (Acari, Hydrachnidia), Journal of Natural History 35 (6), pp. 931-944 : 936-942

Rutripalpus limicola Sokolow, 1934

( Figures 1 ±35)

Material examined

Germany, Baden-WuÈrttemberg ( KN), Radolfzell, Mindelsee, Helocrene SE border, 410 m, 1 June 1988, Schwoerbel, one deutonymph; 19 May 1992, Goldschmidt, one male, two females ; 23 September 1992, Goldschmidt, one deutonymph; 30 September 1992, Godlschmidt, one male.

Yugoslavia, Montenegro ( IG), Murino, Mokra Planina, helocrene near Velika, W C Ïakor pass, 42ss48¾N, 17ss37¾E, 1400 m, 6 June 1990, Gerecke, one male, numerous larvae attached to larva of Ptychoptera .

Description

Male (W gures 1±15). Idiosoma (dorsal view: ®gure 1) L 670±750 m m, W 550 m m, integument covered by a net of ®ne lines formed by the narrow interspaces between ¯at, pillow-shaped papillae; in the specimen from Yugoslavia, dorsolateralia well developed and second pair of dorsocentralia fused medially, forming an H-shaped medial sclerite (L 198 m m, W 130 m m), in the specimens from Germany all dorsocentralia unfused and dorsolateralia nearly invisible; coxae (®gure 2) with a low number of setae, strong and long marginally, but ®ne and shorter on the coxal surface, posteromedial part of Cx-11 2 covered by a pouch of membranous integument; shape and setation of legs: ®gures 3±8; measurements (segments 1±6): (A) specimen from Germany: I-L 67, 54, 76, 100, 100, 112, total 509 m m, II-L 72, 61, 76, 105, 123, 134, total 571 m m; III-L 65, 67, 78, 114, 156, 143, total 623 m m; IV-L 105, 78, 123, 161, 194, 168, total 829 m m; (B) specimen from Yugoslavia: I-L 81, 63, 81, 108, 112, 121, total 566 m m; II-L 81, 67, 85, 121, 135, 139, total 628 m m; III-L 81, 72, 85, 135, 166, 157, total 696 m m; IV-L 130, 90, 139, 175, 215, 198, total 947 m m; genital ®eld (®gures 12±14) with the second acetabulam the largest on the specimen from Montenegro, but the third one in specimens from Germany, genital skeleton (®gure 15) consisting of a small vesicle ¯anked by a pair of wing-like brachia distalia, and by well-developed anterior and posterior carinae, but completely lacking brachia proximalia and proximal horns; ventral margin of gnathosoma (®gure 11) forming a strong ventrodistal angle; chelicera measurements of specimen from Germany (specimen from Montenegro in parentheses): basal segment L 130 (150), H 69 (83), claw 31 (38) m m; pedipalp as given in ®gures 9 and 10; measurements (P-1±5, L / H): 36 / 72, 136 / 94, 52 / 67, 76 / 54, 67 / 29, total L 367 m m.

Female (W gures 16±21). Idiosoma L 780±820, W 600±630 m m, integument, distribution of setae and sclerites as in males, but dorsalia relatively smaller (e.g. dorsocentralia 2 L 94, W 45 m m, ®gure 16), and dorsolateralia visible only as areas of slightly thickened integument; genital ®eld (®gures 17, 18) total L 220±225, W 125±130 m m, genital ¯aps L 140 m m, with undulate medial margin bearing nine setae; praegenital platelet hexagonal, postgenital platelet small, bean-shaped; gonopore long, extending far beyond the anterior edge of genital ¯aps (ratio genital ®eld L / genital ¯ap L 5 1.62±1.75); gnathosoma as in males, chelicera (®gure 21) basal segment L 145, H 69, claw L 34 m m; pedipalp (®gures 19, 20) with P-4 more slender than in males, and P-5 without lateral indentationÐclaws arranged on a continuous convex line; measurements (P-1±5, L / H): 34 / 72, 154 / 96, 61 / 72, 96 / 40, 78 / 22.

Deutonymph (juvenile, W gures 22±24). Idiosoma L 315±430, W 270±340 m m. General morphology similar to adults, but with the following diOEerences: membranous integument ventrally with transverse lines at regular distances enlarged to longish papillae, dorsally, lineation disappearing in favour of densely arranged round papillae; dorsal sclerites visible only as muscle insertion areas with thickened integument (probably due to the juvenile age of the specimens studied, but well sclerotized in more mature deutonymphs); lower number of setae on coxae and appendages (®gures 22, 23), Cxgl-4 embraced by an indentation of the posteromedial margin of Cx-4; genital ®eld (®gure 22) L 40±45, W 61±66 m m, genital ¯aps bearing three to four setae each; in the centre, a rod-shaped, posteriorly enlarged unpaired sclerite; pedipalp measurements (P-1±5, L / W): 23 / 46, 87 / 60, 35 / 45, 60 / 24, 44 / 14 m m.

Larva (unengorged, W gures 25±35). Idiosoma (ventral view ®gure 25, dorsal view ®gure 26) dorsal plate L 230±244, W 170±180 m m, with quadrangular-shape d reticulations anteriorly and rectangular reticulations posteriorly; setae Mh1-4 separate, but in shallow indentations of the dorsal shield, lateral eye lenses on two pairs of platelets (®gure 27); coxal plates with median L of Cx-1±3: 49, 31, 90 m m; urstigma: ®gure 28; excretory plate (®gure 29) trapezoidal, with convex posterior margin; leg morphology as given in ®gures 30±33, dorsal L of segments: I-L-1±5: 40, 26, 39, 49, 62 m m; II-L-1±5: 41, 31, 38, 58, 70 m m; III-L-1±5: 49, 31, 40, 62, 78 m m; leg claws slender, empodium three-tined (®gure 9); gnathosoma L 95 m m, chelicera (®gure 34) basal segment L 70, claw L 17, H 17 m m; pedipalp (lateral view ®gure 35) dorsal L of segments: P-1 10, P-2 40, P-3 35, P-4 12, P-5 22 m m.

Figures

FIGS 1, 2. Rutripalpus limicola male, idiosoma. (1) Ventral view; (2) dorsal view. Bar5 100 mm.