Feltria (Feltria) ussuriensis, Tuzovskij, Petr V. & Semenchenko, Ksenia A., 2009

Tuzovskij, Petr V. & Semenchenko, Ksenia A., 2009, New water mites species of the genus Feltria Koenike (Acariformes, Feltriidae) from the Asian Russia, Zootaxa 2124, pp. 38-50 : 42-45

Feltria (Feltria) ussuriensis sp. n.

( Figs. 9–16 )

Type series. Holotype: female (9493– IBIW), Russia, Primory Territory, Khasansky District, “Kedrovaya Pad National Nature Biosphere Reserve”, Sea of Japan basin, the Kedrovaya River, N 43°06.056’; E 131°33.310’; depth 18–30 cm; substrates: stones, pebbles. 25.11.1993, coll. T.M. Tiunova. Paratypes: 10 females, 1 male (9490-9496– IBIW); 2 females (27-28-kas– IBSS). Paratypes with same locality and date as holotype.

Description. Female. Body flat. Dorsum with large shield and seven pairs of platelets ( Fig. 9 ). Median portion of frontal margin straight. Dorsal shield with four pairs of setae: Oi, Oe, Sci and Li. Setae Fp, Oi and Pi without glandularia, other idiosomal setae associated with glandularia. Dorsal shield with two median furrows and three pairs of small lateral depressions; these furrows various in shape and usually fused to each other caudally. Setae Fch, Fp, Vi, Ve and first pair of lyriform organs (i1) located on narrow anterior plates; setae Hi, He, Sce and Le placed on separate lateral sclerits; second pair of lyriform organs (i2) fused with sclerits, bearing setae Hi. Setae Si placed on relatively large triangular posterior plates. One pair of small platelets located anterolaterally to triangular plates. Three pairs of lyriform organs (i3–i5) usually lying free on smooth membrane, but i4 can be fused with platelets, bearing setae Sce.

Anterior coxal groups fused medially, but suture line between coxae I present; posterior coxal groups close together but not fused medially ( Fig. 10 ). Posterior apodemes of first coxae short and directed more or less laterally. Second coxae not extending to midline. Acetabular plates fused with each other, but trace of a suture line present, its anterior margins forming blunt angle; acetabula very numerous and located mainly in their lateral parts. Gonoporus located in posterior half of acetabular plates and surrounded by a frame, bearing three pairs of anterior setae and one pair of posterior setae. Median portions of acetabular plates fused with posterior extensions of fourth coxae, but trace of a suture line between them present. Pregenital sclerite very small, located between posteromedial corners of posterior extensions of fourth coxae and anterior margin of acetabular plates. Setae Pe and Se and associated glandularia fused with posterior extensions of fourth coxae. Excretory pore platelets free, setae Pi and setae Ci fused with acetabular plate. Capitulum with short anchoral projection.

Pedipalp moderately slender ( Fig. 11 ). Trochanter relatively short, with single dorsodistal seta. Femur expanded, with two proximal and three thick dorsodistal setae, its ventral margin convex. Genu with one proximal and two dorsodistal setae. Tibia long and tapering distally, with two unequal ventral setae and one short distolateral spine. Surface of femur and genu with cell-shaped reticulation, surface of tibia with strips.

First four segments of all legs usually with thick setae ( Fig. 12 ). Claws with three dents: large median, short internal and external ones, but internal claw thicker than external one. Ventral margin of claw plate concave.

Measurements (n=5). Length of body 510–540, width 390–430; length of dorsal shield 420–435, width 310–340; length of seta Fch 18–24; length of genital plate 190–210, width 360–395; length of capitulum 90–96; length of pedipalpal segments (P 1–5): 30–36, 65–72, 48–60, 118–125, 18–27; length of coxae I–IV 360–395; length of leg segments: I — 42 –54, 54–65, 60-64, 69–72, 70–85, 75–90; II — 48 –54, 57–66, 52–55, 65–68, 82–90, 85–95; III — 60 –72, 48–66, 54–66, 75–90, 100–110, 95–102; IV — 70 –95, 65–75, 78–85, 105–115, 120–126, 78–100.

Male. Dorsum with large shield and five pairs of platelets ( Fig. 15 ). Median portion of frontal margin convex. Dorsal shield with five pairs of setae: Oi, Oe, Sci, Li and Si; setae Oi thin, other setae thick. Setae Fp, Oi and Pi without glandularia, other idiosomal setae associated with glandularia. Dorsal shield with two pairs of median furrows and three pairs of small lateral depressions; furrows of anterior and posterior pairs fused to each other distally. Setae Fch, Fp, Vi, Ve and first pair of lyriform organs (i1) located on long, narrow anterior platelets; setae Hi and i2 placed on first lateral platelets, setae He, Sce and Le placed on separated lateral platelets too. Fourth pairs of lyriform organs (i4) located on plates, bearing setae Sce; i3 and i5 lying free on smooth membrane.

Anterior coxal groups fused medially, but suture line between coxae I present; posterior coxal groups close together but not fused medially ( Fig. 16 ). Posterior apodemes of first coxae moderately long and directed more or less laterally. Second coxae not extending to midline. Anterior margin of acetabular plates forming blunt angle; acetabula numerous. Gonoporus small and narrow, located in anterior half of acetabular plates, with two pairs of perigenital setae. Median portion of acetabular plate fused with posterior extensions of fourth coxae, but trace of suture line between them present. Pregenital sclerite very small, located between posteromedial corners of posterior extensions of fourth coxae and anterior margin of acetabular plate. Setae Pe and Se and associated glandularia fused with posterior extensions of fourth coxae. Excretory pore platelet fused with acetabular plate. Setae Pi and setae Ci not fused with acetabular plate. Capitulum with short posterior projection.

Pedipalp similar to that of female, but femur with proximoventral protrusion ( Fig. 13 ).

Tibia of leg III ( Fig. 14 ) with five unequal setae, tarsus with large ventrolateral protrusion, bearing six pointed setae.

Measurements (n=1). Length of body 485, width 355; length of dorsal shield 438, width 288; length of seta Fch 24; length of genital plate 198, width 270; length of capitulum 95; length of pedipalpal segments (P 1–5): 30, 69, 57, 120,?; length of coxae I–IV 385; length of leg segments: I — 50,?,?,?,?,?; II — 54, 60, 57, 69, 102,?; III — 65, 60, 78, 84, 120, 90; IV — 85, 72, 78, 102, 126, 102.

Differential diagnosis. The combination of the following characters separate F. ussuriensis sp. n. from all other species of the subgenus Feltria : the dorsal shield with longitudinal medial furrows and three pairs of the lateral depressions, long pedipalpal tibia, the female’s acetabular plates are fused to each other, and the gonoporus is surrounded by a frame and located in the posterior half of the genital field.

Etymology. The species epithet ussuriensis is derived from the former historical name of the region (Ussuri region) where it was collected.

Habitat. Running waters.

Distribution. Primory Territory, Far East of Russia.

Figures

FIGURES 9 – 10. Feltria ussuriensis sp. n., female: 9, idiosoma, dorsal view; 10, idiosoma, ventral view. Scale bar = 100 μm.

FIGURES 11 – 14. Feltria ussuriensis sp. n., female (11 – 12) and male (13 – 14): 11, pedipalp, medial view; 12, leg I; 13, trochanter, femur and genu of pedipalp, medial view; 14, tibia and tarsus of leg III. Scale bar = 50 μm.

FIGURES 15 – 16. Feltria ussuriensis sp. n., male: 15, idiosoma, dorsal view; 16, idiosoma, ventral view. Scale bar = 100 μm.