Sperchon (Sperchon) urumqiensis, Zhang, Xu & Jin, Dao-Chao, 2011

Zhang, Xu & Jin, Dao-Chao, 2011, New records of water mites of the family Sperchontidae Thor, 1900 from China (Acari, Hydrachnidia), with descriptions of two new species, ZooKeys 158, pp. 89-109 : 97-101

Sperchon (Sperchon) urumqiensis sp. n. Figures 3242

Type series.

Holotype: Male, Xinjiang Uygur Autonomous Region, Urumqi city, Baiyanggou scenic area, an unnamed stream (43°37'42"N, 87°57'18"E), 18 Aug 1996, coll. Dao- Chao Jin. Paratypes: 6 males and 8 females, the same data as the holotype.

Diagnosis.

Cuticle covered with scale-shaped papillae; excretory pore surrounded by a sclerotized ring; P-II with a long ventro-distal projection and one heavy seta close to the ventrodistal margin of P-II; third to fifth segments of leg I-IV with rather long plumose setae in longitudinal rows.

Description.

Male (n = 3):Idiosoma oval in shape, 812 (756-907) in length, 682 (663-712) in width. Cuticle yellow in colour, covered with scale-shaped papillae (Fig. 34). A1 smooth, short and thick, other glandularia thin and long. All glandularia and O2 encircled by a platelet. Some chitinous platelets and glandular platelets on dorsum fused as shown in Fig. 32. Coxae in four groups, surface of coxae reticulated. ACG 163 (158-171) in length, posterior apodeme weakly developed. E2 laterally between ACG and PCG. PCG 242 (236-254) in length. E4 close to anterior margin of CxIII. Distance between anterior end of ACG and posterior end of PCG 443 (432-464). Genital field between PCG with a small and rounded platelet in front. Genital valves not covering the genital acetabula, 188 (182-193) in length, 117 (113-124) in width. Pre- and postgenital sclerites not developed. Three pairs of acetabula, the two anterior pairs of acetabula long elliptic and the posterior pair more or less rounded. An oblong plate posterior to genital field, almost in the middle line of V1 and V3. V1 on very small sclerites and without accompanying glandularia. Excretory pore surrounded by a sclerotized ring and close to the line at V2 glands.

Infracapitulum with a short and heavy rostrum, length 189 (185-197). Chelicera total length 229 (225-237), basal segment length 174 (172-179), claw length 55 (53 - 58), basal segment/claw length ratio 3.2 (3.1-3.2). Dorsal lengths of the palpal segments: P-I, 22 (21-24); P-II, 99 (97-106); P-III, 118 (113-127); P-IV, 171 (165-182); P-V, 37 (34-42). P-I short and with one dorsal seta. P-II with a long ventro-distal projection bearing two thin setae, of which one longer than another. One heavy seta close to the ventrodistal margin of P-II. Seven setae on the dorsal and lateral side of the P-II, none of them plumose. The ventral side of P-III somewhat swelled and without seta, two long smooth setae on the lateral and dorsal side. P-IV slender, much longer than P-III, and with two ventral peg-like setae, of which the proximal one almost at ventral middle of the segment, and the distal one approximately equidistant from proximal one and distal end of the segment. Four thin setae on P- IV, one of them on the median dorsal, two on the dorsal distal and another one on the terminal end of the segment. Dorsal lengths of the first leg: I-L-1, 39 (36-43); I-L-2, 83 (80-90); I-L-3, 98 (90-106); I-L-4, 191 (185-200); I-L-5, 182 (177-193); I-L-6, 179 (174-187). Dorsal lengths of the fourth leg: IV-L-1, 87 (85-94); IV-L-2, 117 (111-128); IV-L-3, 154 (148-168); IV-L-4, 300 (290-317); IV-L-5, 271 (264-285); IV-L-6, 257 (249-266). Third to fifth segments of leg I-IV with rather long plumose setae in longitudinal rows (Fig. 39). Ambulacrum with two claws and each claw with well protruded claw-blade and two clawets, a long dorsal and a shorter ventral one (Fig. 37).

Female (n = 3):Color, idiosoma shape, and the decorations of cuticle as in the male. Characters of the genital field, the fusion and the size of dorsalia and ventralia different from the male (Fig. 41, Fig. 42). Idiosoma 979 (953-1023) in length, 829 (805-876) in width. ACG 202 (197-212) in length, PCG 301 (295-314) in length. Distance between anterior end of ACG and posterior end of PCG 559 (547-578). Genital field 227 (223-234) in length, 245 (241-253) in width. Pre- and postgenital sclerites well developed than that in the male. Infracapitulum length 255 (250-261). Chelicera total length 317 (311-331), basal segment length 244 (241-253), claw length 73 (70-78), basal segment/claw length ratio 3.3 (3.2-3.4). Dorsal lengths of the palpal segments: P-I, 47 (45-50); P-II, 146 (140-155); P-III, 181 (174-193); P-IV, 274 (263-289); P-V, 45 (42-49). Dorsal lengths of leg I: I-L-1, 70 (64-78); I-L-2, 135 (127-148); I-L-3, 128 (122-137); I-L-4, 256 (243-171); I-L-5, 272 (260-284); I-L-6, 234 (222-247). Dorsal lengths of leg IV: IV-L-1, 115 (119-124); IV-L-2, 156 (148-169); IV-L-3, 230 (219-244); IV-L-4, 379 (366-397); IV-L-5, 363 (351-380); IV-L-6, 322 (311-340).

Etymology.

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

Remarks.

Due to the shape of cuticle, E4 on the CxIII and P-II with a long ventro-distal projection, the new species is similar to Sperchon sounkyo Imamura, 1954. From the later species, Sperchon urumqiensis sp. n. can be easily distinguished by the following features: the dorsum and posterior venter with sclerotized muscle attachment plates (Fig. 32-33, Fig. 41-42) (unsclerotized in Sperchon sounkyo , see Fig. 22-23, Fig. 30-31), the presence of a long and heavy seta close to the ventrodistal margin of P-II (Fig. 40) (vs. without heavy seta in Sperchon sounkyo , see Fig. 27), the two peg-like setae of P-IV are sub equal in size (Fig. 40) (proximoventral seta larger than distoventral in Sperchon sounkyo , see Fig. 27), and the excretory pore is sclerotized (Fig. 33, Fig. 42) (smooth in Sperchon sounkyo , see Fig. 23, Fig. 31).

The new species also resemble Sperchon ussuriensis Tuzovskij, 2002 from Russia ( Tuzovskij 2002). However, in Sperchon ussuriensis , the anterior groups of coxae are fused and the excretory pore is unsclerotized. While in the new species, the anterior groups of coxae are not fused and the excretory pore is surrounded by a sclerotized ring.

Distribution.

China (Xinjiang Uygur Autonomous Region).