Radfordia (Microtimyobia) arctica Fain and Lukoschus, 1977

Bochkov, Andre V., 2011, Mites of the subgenus Microtimyobia (Acariformes: Myobiidae: Radfordia) and their host-parasite relationships with cricetid rodents (Cricetidae) 2954, Zootaxa 2954 (1), pp. 1-86 : 42-44

11. Radfordia (Microtimyobia) arctica Fain and Lukoschus, 1977

( Figs. 29–31 )

Radfordia (Microtimyobia) arctica Fain and Lukoschus, 1977: 74 , figs. 73–76, 91, 107

Radfordia (Graphiurobia) macdonaldi Gill and Strandtmann, 1977: 103 , figs. 1–10; syn. nov.

Diagnosis. FEMALE ( Fig. 29 ). Subcapitular setae m with 1–2 tines. Setae vi and e2 subequal. Setae e1 and f1 filiform. Distances c1-d1 and d1-d2 subequal. Vulvar region ornamented with longitudinal striations; anterior margin of vulvar region straight. Setae ps3 distinctly developed, slightly curved. Setae ag2 at least twice longer than ag1. Setae 1b and 1d slightly thicker than 1a. Setae 2a and 3a whip-like, much longer than 2b. Trochanter I with ventral projection, without tubercles. Measurements of paratype from Fain & Lukoschus (1977): body, including gnathosoma, 450 long, 280 maximum wide. Lengths of setae: vi 60, si 105, se 118, c1 75, c2 125, d1 75, d2 78, e1 18, e2 60, 2a and 3a about 100, 4a 40.

MALE ( Fig. 30 ). Subcapitular setae m filiform. Genital cone slightly elongated, length/width ratio 1.4:1, with straight slanting lateral margins without projections. Bases of setae vi situated anterior to setae ps2. Setae f1 1.5–2 times shorter than e2. Posterior end of opisthosoma without tubercles dorsally and with tubercles ventrally. Setae 2b whip-like, much longer than 2a and 3a. Trochanter I with ventral projection, without tubercles. Measurements of holotype ( Fain & Lukoschus 1977): body, including gnathosoma, 310 long, 140 maximum wide. Aedeagus 140 long. Lengths of setae: vi 15, si 36, e1 51 –46, e2 45, f1 30, 2a 18, 3a 19, 4a 33.

FEMALE TRITONYMPH ( Fig. 31 ). Setae f2 and h2 stick-like, other dorsal idiosomal setae narrow lanceolate. Setae 3a and 4a short, much shorter than 2a. Tarsus IV bearing only setal alveoli.

Remark. Bochkov (1995) mentioned the probable conspecificity of Radfordia arctica and Radfordia macdonaldi Gill and Strandtmann, 1977 described from Dicrostonyx torquatus from Canada (Bathurst Island). Both species were described in the same year, on 23 January 1977 and 20 August 1977, respectively, and Gill and Strandtmann did not know about the work of their European colleagues. I formally synonymize Radfordia macdonaldi syn. nov. with Radfordia arctica here based on comparative material from three host species of the genus Dicrostonyx .

Type host and locality. Dicrostonyx groenlandicus from Greenland ( Fain & Lukoschus 1977).

Hosts and distribution. This species is associated with voles of the genus Dicrostonyx ( Bochkov 1995) .

It was recorded from:

Dicrostonyx groenlandicus from Greenland ( Fain & Lukoschus 1977);

Dicrostonyx torquatus from Canada (Bathurst Is.) ( Gill & Strandtmann 1977) and Russia (Taymyr) ( Bochkov 1995);

Dicrostonyx vinogradovi (new host) from Russia (Wrangel Island).

Material examined. Dicrostonyx groenlandicus — 1 female paratype ( ZISP), GREENLAND: Jamesoland , 1932, coll. unknown .

Dicrostonyx torquatus — 1 male, 5 females, 2 female TN ( ZISP), RUSSIA: Taymyr, Tareya-Pyasina River , June–July 1976, coll. E. Dubinina ; 5 males and 4 females ( AVB 09-1201 - 017 ), ( ZISP 60943 ), RUSSIA: Arkhangelsk Prov., Novaya Zemlya Archipelago, Zhelaniya Cape , 76°57'16.08"E, 68°34'54.41"E, 2 July 1935 , coll. unknown.

Dicrostonyx vinogradovi — 1 female and 1 female TN ( AVB 09-1202 - 001 ) ( ZISP 30780 ), RUSSIA: Wrangel Island , near Roger’s Bay, 23 August 1938, coll. unknown .

Type depositions. Radfordia arctica —MNHN, male holotype (no. 955/8 E16) (not examined); Radfordia macdonaldi —BRI, female holotype (not examined).

Figures

FIGURE 29. Radfordia (M.) arctica Fain and Lukoschus, 1977 from Dicrostonyx torquatus, female. A, dorsal view; B, ventral view; C, seta m; D, vulvar region. Scale bars: A, B = 100 µm; C, D = 50 µm.

FIGURE 30. Radfordia (M.) arctica Fain and Lukoschus, 1977 from Dicrostonyx torquatus, male. A, dorsal view; B, ventral view; C, genital cone. Scale bars: A, B = 100 µm; C = 50 µm.

FIGURE 31. Radfordia (M.) arctica Fain and Lukoschus, 1977 from Dicrostonyx torquatus, female tritonymph. A, idiosoma in dorsal view; B, same in ventral view; C, leg IV in ventral view. Scale bars: A, B = 100 µm; C = 50 µm.