Atractides inflatipes Lundblad, 1956

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 : 2-4

Atractides inflatipes Lundblad, 1956 ( Figs. 1–3 )

Atractides distans inflatipes Lundblad, 1956

[syn. to A. distans K. Viets, 1914 : Lundblad (1962) ­ rejected synonymy (Gerecke in prep)] Atractides inflatipes Lundblad, 1956 – Gerecke (in prep.)

Material examined: Yugoslavia ( Crna Gora) – CG31 River Cijevna near Dinosa (Podgorica reg.), 0 1.07.2000, 2, leg. Pesic.

Description

Female (n=2; in parentheses measurements of holotype [from Gerecke (in prep.)]): Length of idiosoma 664 (620), width 486 (415). Dorsally the integument is striated; muscle attachments smooth; glandularia 21 (21). Length between anterior end of first coxae and posterior end of fourth coxae 315­321 (320); Cx­3 width 358­384 (360); Cx­1+2 width 269­277 (265); Cx­1+2 medial suture 98­104 (117) in length; distance from lateralmost tips of Cx­2 to medioposterior edge of Cx­2+3 191­196 (198). Measurements of mouthparts: palp total length 296­306 (319), dorsal length of single segments: P­1 32­33 (30), P­2 64­67 (70), P­3 74­81 (84), P­4 92­93 (102), P­5 33­32 (33); length ratio P­2/P­4 0.69 (0.69); palp: slender; P­2 ventral margin very weakly convex, nearly straight, forming a right distal angle; P­3 ventrally straight; P­4 with a slight ventral indentation and a sword seta near distoventral hair ( Fig. 1 ). Genital field: praegen narrow, Ac in a weakly curved line ( Fig. 3 ); genital field 136 (153) in length, 155 (148) in width, Ac­1­3 length 33­32.5­ 32 (30­35­30); excretory pore smooth; Vgl­1 separate from Vgl­2.

I­L: I­L­5 considerably thickened at insertion S­1, with ventral seta inserted very close to S­1; S­1­2 distanced, heteromorphic, thickened; I­L­6 curved, very slender ( Fig. 2 ); I­L­ 5 dorsal length 188–206 (215), I­L­5 ventral length 107­110 (125), ratio dorsal length I­L­ 5/ventral length 1.76­1.87 (1.72), I­L­5 central height 65.7­70 (71), ratio dorsal length I­ L­5/central height 2.7­3.1 (3.03), S­1 length 110.5­117 (125) Pm, ratio length S­1/ width 8.7­8.8 (8.9), S­2 length 74­83 (83) Pm, ratio length S­2/ width 4.3­4.5 (4.9), distance of sword setae at I­L­5 39­44 (49); length ratio S­1/2 1.42­1.5 (1.51); I­L­6 length 150­154 (176), I­L­6 central height 16 (16), ratio length I­L­6/central height 9.4­9.9 (11.0); length ratio I­L­5/6 1.23­1.33 (1.22).

Remarks: The original description of Atractides inflatipes Lundblad, 1956 was based on a female specimen (Holotype, SMNH '4104 Typ.' ' Atractides distans inflatipes Ldbl.. France, Bains du Boulou. 29.5.1935. Leg. O. Lundblad') and a male specimens (paratype '4374 Allotyp.' ' Atractides distans inflatipes Ldbl.. Spanien. Granada. 12.6.1935. Leg. O. Lundblad') ( Lundblad 1956). After that occasion no more records of this species are known. Atractides distans ( K. Viets, 1914) is similar to A. inflatipes in a rather low I­L­5 L/HB ratio (3.14), but differs in a lower L ratio I­L­5/6 (1.03), and by far more slender S­1 (L/ W 16.1, with distally enlarged and truncate tip) and S­2 (L/ W 9.9) (Gerecke, in prep). Lundblad expressed his doubt if the designated paratype male of A. inflatipes was really conspecific with the female. The specimen on slide SMNH 4374 is similar to the holotype in several proportions, e.g. the considerably 'inflated' I­L­5 with rather distant setae S­1/2. A very important difference is the fusion of Vgl­1+2. According to Gerecke (in prep.), a sexual dimorphism regarding this character is rare in Atractides , and if it is expressed, in the sex with fused Vgl­1+2 the platelet is always '8'­shaped, not equally round as in SMNH 4374. This evidence is sufficient for considering the two specimens not conspecific. In one of the females in Montenegro, Vgl­1+2 on the left side is fused in the '8'­shaped platelet. Thus, the paratype male of A. inflatipes could represent an undescribed species (Gerecke in prep.). Most dimensions and proportions of the specimen from Montenegro agree with the holotype. Differences are found in shorter medial suture of Cx­1+2, and a generally shorter I­L, with slightly more stout I­L­6. In view of the good agreement in proportions these differences are most probably age­depending and/or due to geographical variability.

Habitat: rhithrobiont.

Distribution: Presently, Atractides inflatus is known from the French Pyrenees and Montenegro, but its distribution is probably more extended. The only two findings in widely separate geographical regions are probably due its rareness as well as to our restricted knowledge of the genus Atractides Koch in large parts of the Mediterranean region. Furthermore, the attribution of the Montenegrin populations to the species should be verified by studies on male specimens.

Figures

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