Sperchon fuxiensis Zhang

Ding, Jian-Hua, Sun, Jing-Lan & Zhang, Xu, 2017, A new species of the water mite genus Sperchon Kramer, 1877 from China, with identifying Sperchonrostratus Lundblad, 1969 through DNA barcoding (Acari, Hydrachnidia, Sperchontidae), ZooKeys 707, pp. 47-61 : 50

Sperchon fuxiensis Zhang sp. n. Figures 1-3, 4-9

Type series.

Holotype: Female, Anhui Province, Fuxi village, Monkey Valley scenic area, an unnamed stream (30°04'16"N; 118°09'26"E), 8 September 2016, coll. Xu Zhang. Paratypes: 1 female, the same data as the holotype.

Diagnosis.

Integument fine spinules arranged in hexagonal pattern; A1 smooth; excretory pore surrounded by a sclerotized ring; P-II with a long ventro-distal projection and one thick seta; third to fifth segments of leg I-IV with short plumose setae.

Description.

Female (n = 2): Body oval in shape, 948 (965) in length, 837 (842) in width. Integument yellow in colour, covered with very fine spinules arranged in hexagonal pattern (Fig. 3). A1 short, smooth and thick, other dorsal setae long and thin. Chitinous plates and glandular plates on both dorsum and venter well developed as illustrated in Fig. 1 and Fig. 2. The heart-shaped platelet between D2 somewhat bluish. Coxae in four groups, surface of coxae reticulated. ACG 92 (98) in length, apodeme well developed. E2 laterally between ACG and PCG. PCG 220 (231) in length. E4 absent from CxIII. Distance between anterior end of ACG and posterior end of PCG 373 (380). Genital field 205 (207) in length, 171 (175) in width. Pre- and postgenital sclerites developed. Three pairs of genital acetabula, the first pair of genital acetabula elliptical, the second pair somewhat triangular, and the third pair rounded and larger than the anterior two pairs. V1 on small sclerites and without accompanying glandularia. Excretory pore between V2, and with a sclerotized ring.

Capitulum with a long rostrum, length 213 (219). Chelicera total length 219 (226), basal segment length 158 (164), claw length 61 (62), ratio of basal segment /claw length 2.6. Dorsal lengths of the palpal segments: P-I, 22 (23); P- II, 123 (127); P-III, 172 (178); P-IV, 178 (183); P-V, 36 (37). P-I short and without seta. P-II with a long ventro-distal projection bearing one long setae. Approximately ten setae on the lateral and dorsal side of P-II and none of them plumose. The ventral side of P-III nearly straight and without seta, four short smooth setae on the lateral and dorsal side. P-IV with two small peg-like ventral setae, one larger almost in the middle, another one near the ventral distal end.

Legs. Dorsal lengths of leg I: I-L-1, 53 (55); I-L-2, 76 (80); I-L-3, 78 (81); I-L-4, 132 (139); I-L-5, 138 (142); I-L-6, 130 (137). Dorsal lengths of leg IV: IV-L-1, 92 (99); IV-L-2, 126 (135); IV-L-3, 129 (137); IV-L-4, 231 (243); IV-L-5, 225 (231); IV-L-6, 193 (198). Third to fifth segments of leg I-IV with rather short plumose setae in longitudinal rows (Fig. 9). Ambulacrum with two claws. Claws with well protruded claw-blade and two small claws, a long dorsal and a shorter ventral one (Fig. 8).

Etymology.

The species is named after the village where it was collected.

Remarks.

Due to the shape of the integument, P- II with a very long ventrodistal projection, excretory pore surrounded by sclerotized ring, and third to fifth segments of leg I-IV with plumose setae, the new species is similar to S. hispidus Koenike, 1895 and Sperchon indicus Kumar, Kumar & Pesic, 2007 ( Kumar et al. 2007, Tuzovskij 2010). However, the new species differs from the two species in the shape of the acetabula. In S. hispidus and S. indicus , three pairs of acetabula are large and arranged densely, whereas in the new species, the three pairs of acetabula are relatively small and arranged loosely with large gaps. The new species also differs from S. hispidus and S. indicus in the shape of apodemes of anterior coxae, which are indistinct in S. hispidus and S. indicus , but well developed in the new species. Besides, E4 is situated on CxIII in S. hispidus and S. indicus , but absent from CxIII in the new species.

Distribution.

China (Anhui Province).