Pseudofeltria scourfieldi Soar, 1904

Gerecke, R., 2014, Pseudofeltria (Acariformes: Pionidae) In Europe: Three Previously Described Taxa, A Species New To Science From The Northern Apennines, And A Redefinition Of Foreliinae, Acarologia 54 (1), pp. 57-67 : 61-63

Pseudofeltria scourfieldi Soar, 1904

(Syn. Pseudofeltria scutigera Walter, 1922: Gledhill, 1960)

( Figure 3 )

Material examined — Germany, Upper Bavaria, Berchtesgaden National Park, Sommerbichel , coll. Gerecke: D BGL 696, spring SW Herrenroint, 1300 m, 12°58’20” E, 47°34’40” N – 13.06.1994 (0/9/1); D BGL 312 spring complex Herrenroint , rheohelocrene, 1150 m, 12°58’30” E, 47°34’50” N – 10.06.1996 (3/2/0); 19.06.1998 (1/1/2); 24.06.2000 (0/1/0). Bulgaria BU flö117, Rila mountains, River Rila catchment, spring seep SW slopes of Popenmütz above Suchoto jezero , 2250 m, 01.08.1966 Flössner leg.

Diagnosis — Both sexes: Genital field with 9-12 pairs of Ac, these often longish, maximum diameter of the largest 22 – 30 µm. Male and female dorsum with one large shield including postocular setae at anterior margin, and posterolaterally two pairs of dorsoglandularia. P-4 with a pair of strong dorsal setae in distal third.

Description:

Both sexes — Colour yellow to brownish. Membranous parts of integument strongly striated, sclerites with a very fine porosity arranged in roundish or longish groups. Palp: P-1 with a stout dorsal seta, P-2 with 5 dorsal setae, ventral margin nearly straight, with a weakly developed projection in distal third; P-3 ventral margin concave, dorsal margin convex, one dorsomedial seta, a pair of stronger developed dorsodistal setae; P-4 robust, dorsally with three setae, one fine in centre, two strong in distal third, ventral margin with a pair of fine setae near a small pointed projection in distal third, distal margin with a strong, pointed peg seta. P-5 stout, with 4 strong claws.

Males — Idiosoma length/width 450 – 515/370 – 395; dorsal shield length/width 390 – 430/260 – 290 (ratio 1.3 – 1.5); coxal shield length/width of Cx-III, 330 – 370/340 – 350 (ratio about 1.0); gonopore length 70 – 90. IV-L-3 and -4 shortened, distally enlarged, both with one small peg-like seta at dorsolateral margin; distal setae: IV-L-3 one pair, rather short, IV-L-4, 6-8, long. IV-L-5 proximally narrow, distally strongly enlarged, ventral margin convex, dorsal margin concave, with three stout dorsal setae and about 8 long, blade-like ventral setae, all inserted in distal half. IV-L-6 ventral margin in proximal part concave, distally rather straight, dorsal margin in centre with a deep inlet bordered by about ten densely arranged stout setae, these in proximal part longer than in distal part. Claws long, simple sickle-shaped. Length/height IV-L-2, 58 – 98/50 – 75, ratio 1.1 – 1.3; IV-L-3, 73 – 83/48 – 55, ratio 1.4 – 1.7; IV-L-4, 85 – 95/56 – 61, ratio 1.4 – 1.6; IV-L-5, 153 – 175/65 – 71, ratio 2.2 – 2.5; IV-L-6, 175 – 188/basal 43 – 48, central 19 – 30, distal 40 – 45. Length ratio IV-L-4/5, 0.54 – 0.58; IV-L-4/6, 0,45 – 0,53; IV-L-5/6, 0.81 – 0.97. Gnathosoma length 160 – 175, chelicera length 180, basal segment/claw ratio 2.4, length/height 3.4. Palp total length 295 – 305; length/height (ratio, % total length) P-1, 36 – 38/40 – 41 (0.91 – 0.94, 12 – 13 %); P-2, 88 – 93/65 – 66 (1.32 – 1.42, 30 %); P-3, 50 – 51/44 – 48 (1.08 – 1.14, 16 – 17 %); P-4, 84 – 88/43 – 45 (1.94 – 1.97, 28 – 29 %); P-5, 35 – 38/18 – 20 (1.88 – 2.00, 12 %). Length ratio P-2/P-3, 1.71 – 1.85; P-2/P-4, 1.03 – 1.06; P-3/P-4, 0.57 – 0,60.

Females — Idiosoma length/width 570 – 590/460 – 490; dorsal shield length/width 440 – 470/285 – 310 (ratio 1.5 – 1.6); coxal shield length/width of Cx-III, 370 – 390/380 – 405 (ratio about 1.0); gonopore length 175 – 180. IV-L without particular characteristics. Gnathosoma length 150 – 175, chelicera length 168, basal segment/claw ratio 2.2, length/height 3.2. Palp total length 316 – 323, more slender than in males (in particular P-2 and P-4): length/height (ratio, % total length): P-1, 38 – 43/41 – 44 (0.91 – 0.97, 12 – 13 %); P-2, 93 – 98/58 – 60 (1.60 – 1.63, 29 – 30 %); P-3, 50 – 55/46 – 49 (1.03 – 1.14, 16 – 17 %); P-4, 94 – 95/38 – 40 (2.38 – 2.50, 29 – 30 %); P-5, 38 – 40/18 – 20 (1.87 – 2.00, 11 – 13 %). Length ratio P-2/P-3, 1.77 – 1.85; P-2/P-4, 0.99 – 1.04; P-3/P-4, 0.53 – 0,59.

Discussion — The idiosoma and palp measurements of the Bavarian populations lie within the size range given by Gledhill (1960) except for the, absolutely and relatively, slightly longer P-3. Furthermore, with an idiosoma length of 618 – 636 µm, females from the English lake district are larger than both the holotype (560) and the Bavarian specimens, but Schwoerbel (1959) published intermediate size ranges (558 – 625 µm) from females collected in Alsace ( France). The holotype male of P. scutigera is minor in size than the minima calculated for populations from Bavaria (see above) and from the English Lake district ( Gledhill 1960), but does not show remarkable differences in proportions. No data were previously published for single leg segments. The specimen from the Bulgarian Rila mountains agrees in number and shape of Ac, but differs in the presence of an additional small sclerite platelet in the posterior dorsal furrow.

Figures

FIGURE 3: Pseudofeltria scourfieldi (D BGL 312): A-B female; A – dorsum; B – palp; C-D male; C – venter; D – IV-L-2-6. Bars = 100 µm.