Wankeliella intermedia Potapov & Stebaeva 1997

Wankeliella intermedia Potapov & Stebaeva, 1997, new record to China

Figures 20–31, Table 3

Material examined. 3 females (slide Nos. XJ-2016005, XJ-2016006-1, XJ-2016006-2), 1 male (slide No. XJ- 2016007), Northwest China, Xinjiang Province, Aletai City, Buerjin County, Hemu village, 48°33’ N 87°25’E, elev. 1150 m, soil samples from broad-leaf forest, 20-VIII-2016, C.W. Huang coll.

Diagnosis. Postantennal organ composed by 6 or 7 parallel lying vesicles; Pseudocelli as type I with formula as 11/022/11111, Th. II and III each with two pairs of pseudocelli; Th. II and III each with 6 m-setae (m3 absent); seta px on Abd. IV present; on Abd. V, setae a1–3 as microsetae, a4 as macroseta, sensillum p3 spindle shaped.

Description of Chinese materials. Adult body 0.51 mm long on average (0.47–0.55 mm, n = 4). Dorsal setae well differentiated into micro- and macrosetae (Figs 25–29). Granulations on body coarse. Pso formula as 11/022/11111 from head to abdomen, 6–8 μm in diameter, type I (Figs 23, 25–29). Th. II and III each with two pairs of pso, subdorsal one between setae p3/p4, close to p3, lateral one posterior to seta m5 (Figs 25–26); pso on Abd. I–IV posterior to seta p3 (Figs 27–29), on Abd. V between the borders of Abd. V and VI.

Cephalic seta a0 and sd5 as mesosetae, 6–8 μm, c1 absent, oc2 as macroseta, 11–14 μm (Fig. 20). Postantennal organ 15–16 μm long and 5–6 μm wide, composed by 6 or 7 parallel lying vesicles in two rows (Figs 21–22). Labrum with 4/5/4 setae. Labium with 5 papilla, 6 apical guard setae, 6 proximal setae, 4 basomedian setae, and 5 basolateral setae (Fig. 24).

Antenna (70–75 μm) shorter than head (80–85 μm) (Fig. 21). Antennal segment IV with four thickened sensilla a–d; sensilla a, c, d curved toward inside, b long, e slender. Small microsensillum, subapical organite and one apical vesicle present. Antennal organ III consists of two small sensory rods concealed behind one large papilla and two thick sensory clubs bent toward each other (Fig. 21), with four guard setae; one large ventral sensory club present.

Legs short, without clavate tibiotarsal hairs (Fig. 31). Coxa, trochanter, femur and tibiotarsus with 3/7/7; 5/5/4; 9/9/9; 11/11/11 setae on Leg I, II and III respectively. Claw 10 μm long (Fig. 31), with minute empodial appendage (3–4 μm). Anal lobes with seta 12' and l3' present (Fig. 30). Anal spines short, 7–8 μm long.

Adult chaetotaxy given in Figs 25–29 and Table 3. Microsensilla present on Th. II–III, lateral sensilla 19–22 μm long (Fig. 26). Th. II and III each with 6 m-setae, m3 absent (Figs 25–26). Thorax with 0, 2, 2 ventral setae. Abd. I–III with 2+2 axial setae each, Abd. I with m4, Abd. II–III with setae m3 and m4 present (Figs 27–28). Abd. IV with setae m4 and px present, p1 as macrosetae (15–16 μm), p2 as microseta (10 μm), p4 as microseta (Fig. 29). Abdominal segment V (Fig. 29) with sensillum p3 spindle-like, 10–11 μm in length; seta a4 (20 μm) and p2 (18–22 μm) as macroseta. Crescentic ridges on abdominal segment VI present.

1 seta m2 and m3 absent; 2 seta m4 present; 3 seta m3 and m4 present; 4 seta px present, p1>p2; 5 setae a1–3 as microsetae and a4 as macroseta; 6 sensillum p3 spindle-like, seta p2 as macroseta; 7 female genital plate with 5 circumgenital and one pair of eugenital setae.

Ventral tube with 4+4 apical setae and 2+2 basal setae (Fig. 31). Abd. II, III and IV with 20, 24, and 27 ventral setae respectively. Female genital plate with 5+5 pregenital setae, 5 circumgenital setae, one pair of eugenital setae and 2 pairs of post-genital setae.

Distribution. China (Xinjiang), Russia (Tuva, North Siberia), Norway.

Remarks. Wankeliella intermedia was originally described from Tuva of Russia, and recorded in North Norway and North Siberia later. The morphology of Chinese specimens is nearly the same as types. As noted by the author in the original description, the PAO of this species is not in the typical shape compared with other congeners. As a consequence, it was placed in the genus Wankeliella temporarily.