Atractides (Atractides) schwoerbeli Lundblad 1969
Creators: name: Pesic, Vladimir
name: Smit, Harry
Publisher: name: Zenodo
Year: 2009
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Trombidiformes
Hygrobatidae
Atractides
Atractides schwoerbeli

description: Atractides (Atractides) schwoerbeli Lundblad, 1969
(Figs. 9A–D, 10A–B, 11A–B, 12A–D, 13A–C)
Material. THAILAND: stream W of Bankrang Camp, Kaeng Krachan NP, 30.xi.2007, 12° 48.106 N 99° 26.786 E, leg. Smit, 2/ 3juveniles /0 (2/1/0 mounted); River at km. 13, alt. 465 m, Doi Inthanon NP, 25.xi.2007, no GPS-coordinates, leg. Smit, 2/5/0 (1/1/0 mounted); stream downstream of Siriphum Waterfall, Doi Inthanon NP, alt. 1300 m, 26.xi.2007, no GPS-coordinates, leg. Smit, 0/2/0 (0/1/0 mounted); stream downstream of Huoay Meng waterfall, between Chiang Saen And Chiang Khong, 20.xi.2007, 20° 18.095 N 100° 22.454 E, leg. Smit, 3/7/0 (1/1/0 mounted). MALAYSIA: Jerian stream, Fraser’s Hill, 14.ii.2009, 3° 43.479 N 101° 42.935 E, alt. 1011 m, leg. Smit, 1/4/0 (1/1/0 mounted); Jerian stream, Fraser’s Hill, 16.ii.2009, 3° 43.475 N 101° 42.935 E, alt. 1011m, leg. Smit, 3/0/0 (1/0/0 mounted).
Morphology. General features. Integument dorsally striated. Muscle attachment plates unsclerotized. Genital field: Ac in triangular arrangement; excretory pore smooth; Vgl-1 separated from Vgl-2. Palp: weak sexual dimorphism; P-2 ventral margin straight, sword seta of P-4 between ventral hair insertions. I-Leg: I- Leg-5 thickened, setae S-1 and -2 distanced, S-1 slender, slightly curved, S-2 enlarged, both with blunt tips; I- Leg-6 curved, thickened basally.
Male (from stream W of Bankrang Camp, Thailand, n=2; in parentheses specimen from stream downstream of Huoay Meng waterfall, Thailand; in square brackets specimens from River at km. 13, Thailand). Idiosoma L/W 409-419 (459) [438]/303-319 (344). Coxal field (Fig. 9A): L 256 (284) [291], Cx- 1+2 mL 103-106 (122), Cx-3 W 284-288 (319) [306], Cx-1+2 lL 175-178 (197) [197]. Palp (Fig. 9C): total L 213-219 (231) [248], dL: P- 1 23-24 (23) [26], P-2 46-47 (49) [53], P-3 52-55 (59) [61], P-4 65-68 (74) [78], P-5 26 (26) [30]; %L: P-1 10.8-11.0 (10.0) [10.5], P-2 21.0-22.1 (21.2) [21.4], P-3 24.4-25.1 (25.5) [24.6], P- 4 30.5-31.1 (32.0) [31.5], P-5 11.9-12.2 (11.3) [12.1]; L P-2/P-4 0.72 (0.81) [0.72]. Genital field (Fig. 9B): anterior margin equally convex, posterior margin indented, L/W 77 (91) [96]/85-89 (96) [94], L Ac-1-3: 27-28 (33) [32]: 29-30 (32) [33]: 30-36 (37) [36].
I-Leg (Fig. 9D): I-Leg-5 dL 130-133 (147) [152], vL 86-92 (98) [], dL/vL 1.45-1.51 (1.5) [], HB 42-44 (46) [49], dL/HB 3.0-3.1 (3.2) [3.1], S-1 L 74 (81) [83], L/ W 9.9 -10.8 (10.7) [10.4], S-2 L 64 (65) [67], L/ W 5.3 (5.4) [5.6], distance of sword setae at I-Leg-5 16 (19) [18], L S-1/2 1.16 (1.25) [1.24]; I-Leg-6 L 99-100 (111) [117], HB 16-18 (17) [18], L/HB 5.4-6.3 (6.6) [6.5]; L I-Leg-5/6 1.3-1.33 (1.32) [1.3].
Female (from stream downstream of Huoay Meng, Thailand; in parentheses juvenile specimen from stream W of Bankrang Camp, Thailand; in square brackets specimens from River at km. 13, Thailand). Idiosoma L/W 663 (394) [813]/488 (297) [644]. Coxal field (Fig. 10A): L (294) [383], Cx-3 W (316) [484], Cx-1+2 mL 135 (125) [144], Cx-1+2 lL 219 (209) [259]. Palp (Fig. 10B): total L 313 (292) [342], dL: P-1 28 (27) [30], P-2 64 (59) [70], P-3 91 (80) [95], P-4 97 (92) [109], P-5 33 (34) [38]; %L: P-1 9.0 (9.3) [8.8], P-2 20.5 (20.2) [20.5], P-3 29.1 (27.4) [27.8], P-4 31.0 (31.5) [31.9], P-5 10.5 (11.6) [11.1]; L P-2/P-4 0.66 (0.64) [0.64]; ventral margin P-3 and -4 straight. Genital field (Fig.): L [156], W 147 () [171], genital plate L 115 (101) [122], L Ac-1-3: 39 (38) [44]-42 (38) [46]-45 (38) [46].
I-Leg (Fig. 11 A-B): I-Leg-5 dL 206 (191) [216], vL 136 (123) [144], dL/vL 1.52 (1.55), [1.5], HB 62 (62) [65], dL/HB 3.3 (3.1) [3.3], S-1 L 112 (105) [121], L/ W 10.6 (10.5) [11.4], S-2 L 85 (81) [94], L/ W 5.2 (5.6) [5.6], distance of sword setae at I-Leg-5 29 (29) [33], L S-1/2 1.3 (1.3) [1.3]; I-Leg-6 L 147 (137) [168], HB 17 (16) [20], L/HB 8.5 (8.6) [8.5]; L I-Leg-5/6 1.4 (1.39) [1.29].
In addition we give measurements of the females from Jerian stream, Malaysia which are suspected to belong to the same species (general differences see below in the “remarks”-section).
Male (n=2). Idiosoma L/W 380-413/297-322; glandularia maximum diameter 25. Coxal field (Fig. A2A): L 248-281, Cx-3 W 279-313, Cx-1+2 mL 114-127, Cx-1+2 lL 174-194. Palp (Fig. 12C): total L 222 (217), dL: P-1 24 (23), P-2 44 (47), P-3 56 (55), P-4 72 (68), P-5 26 (24); %L: P-1 10.8 (10.6), P-2 19.8 (21.7), P-3 25.2 (25.3), P-4 32.4 (31.3), P-5 11.7 (11.1); L P-2/P-4 0.61 (0.69). Genital field (Fig. 12B): L/W 78-80/ 79- 88, L Ac-1-3: 24-30: 24-32: 29-33.
I-Leg (Fig. 12D): I-Leg-5 dL 142-152, vL 81-89, dL/vL 1.7-1.76, HB 46-47, dL/HB 3.1-3.2, S-1 L 91-97, L/ W 10.7 -12.0, S-2 L 68-69, L/ W 5.3 -5.7, distance of sword setae at I-Leg- 5 24-28, L S-1/2 1.3-1.43; I-Leg-6 L 121-124, HB 16, L/HB 7.6-7.7; L I-Leg-5/6 1.18-1.23.
Female. Idiosoma L/W 656/516. Coxal field (Fig. 13A): L 306, Cx-3 W 378, Cx-1+2 mL 121, Cx-1+2 lL 206. Palp (Fig. 13C): total L 278, dL and %L (in parentheses) P-1 26 (9.4), P-2 56 (20.1), P-3 76 (27.3), P-4 87 (31.3), P-5 33 (11.9); L P-2/P-4 0.64. Genital field (Fig. 813A): L/W 135/153, genital plate L 94, L Ac-1- 3: 32-33-38.
I-Leg (Fig. 13B): I-Leg-5 dL 183, vL 108, dL/vL 1.69, HB 58, dL/HB 3.16, S-1 L 129, L/ W 12.2, S-2 L 99, L/ W 5.7, distance of sword setae at I-Leg-5 35, L S-1/2 1.3; I-Leg-6 L 163, HB 18, L/HB 9.3; L I-Leg-5/6 1.12.
Remarks. The specimens from Thailand agree with Atractides schwoerbeli, known from Burma (Lundblad 1969) due to the presence of striated dorsal integument, a weak sexual dimorphism of P-2, a narrow S-1 and -2 interspace, thickened I-Leg-6 and a long and slender I-Leg-6. The males have a Vgl-3 fused to Cx-4, but this character is known to be variable (see Figs. 9A, 12A).
The specimens from Jerian stream, Malaysia, differ from specimens of A. schwoerbeli from Burma (see Lundblad 1969) and our material from Thailand in a slightly more distant S-1 and S-2 on I-Leg-5 and more slender I-Leg-6. Further studies on the variability of populations of A. schwoerbeli are necessary before we can assess the taxonomic status of these specimens.
Distribution. Burma (Lundblad 1969), Sri Lanka. New for Thailand and Malaysia.
description: Published as part of Pesic, Vladimir & Smit, Harry, 2009, New records of water mites of the genus Atractides Koch, 1837 (Acari: Hydrachnidia, Hygrobatidae) from Thailand, Malaysia and Sulawesi (Indonesia), with the description of four new species, pp. 1-30 in Zootaxa 2240 on pages 14-19, DOI: 10.5281/zenodo.190536