Unionicola (Unionicola) suiyangensis Ding & Jin, 2019

Ding, Zhuhui, Jin, Daochao, Guo, Jianjun & Yi, Tianci, 2019, Three new species of the subgenus Unionicola Haldeman, 1842 (Acari, Hydrachnidia, Unionicolidae) from Guizhou, China, Zootaxa 4658 (1), pp. 141-154 : 150-152

publication ID	https://doi.org/ 10.11646/zootaxa.4658.1.6
publication LSID	lsid:zoobank.org:pub:7E2D1126-13E1-4615-872A-241F77849483
persistent identifier	https://treatment.plazi.org/id/DA198791-FFF2-FF83-12FE-E41B5793734B
treatment provided by	Plazi
scientific name	Unionicola (Unionicola) suiyangensis Ding & Jin
status	sp. nov.

Treatment

Unionicola (Unionicola) suiyangensis Ding & Jin , sp. nov.

( Figs. 7 View FIGURE 7 , 8 View FIGURE 8 , 9 View FIGURE 9 )

Material examined. Holotype: ♀, GZ-UN-2006072302, Zhenchang town, Suiyang county , Guizhou province, Chi- na (27°55′8″N 107°12′29″E, H. 1149 m a.s.l.), collected by Tianci Yi, 23-VII-2006 GoogleMaps , Paratype: 3 ♂♂, 3 ♀♀, same data as holotype GoogleMaps .

Diagnosis. Dorsum with two pairs of small unequal platelets; L 2, L 3 and D 2 nearly at the same level; V 2 dorsally located, with relatively developed sclerites and larger glands than dorsal glandularia; P-2 with three setae, the distal one longer than others; P-4 with rather long ventrodistal, very long lateral and stubby ventroproximal projection; base of infracapitulum with one toe-like projection; genital plates of female with acetabula in two groups, each anterior plate with two short and stout setae, each posterior plate with one; I-L-6 and II-L-6 with one dorsoproximal seta, respectively.

Description. female. Idiosoma elliptical; dorsum with two pairs of platelets ( Figs. 7-E View FIGURE 7 ), the anterior pair larger; excretory pore slightly posterior to L 4. Coxal plates in four groups ( Figs. 7-F View FIGURE 7 ), surface lightly reticulated ( Figs. 8- E View FIGURE 8 ); posterior apodemes of ACG relatively short, sickle shaped; suture line of Cx-III/IV curved forward, and ending nearly at median of Cx-III; Cx-III with wavy strae; PCG anteriorly and posteriorly with secondary sclerotization; interspace between ACG and PCG relatively wide. Medial margins of genital plates raised with three pairs of short stout inner setae, of which two pairs on anterior plates ( Figs. 7-D View FIGURE 7 ).

Palp slender ( Figs. 8-F View FIGURE 8 ); P-2 with four setae, of which the distal one longest; P-3 with a pair of similar setae; P-4 laterally with one long proximal seta and three well developed projections, the lateral one longest, ventroproximal one stubby, and the proximal two each bearing a thin seta; P-5 curved and smooth, proximally with one seta. Ventral apodeme of infracapitulum almost straight, a toe-like projection present at base of ventral apodeme of infracapitulum ( Figs. 8-B View FIGURE 8 ). Chelicera with well-developed claw ( Figs. 8-C View FIGURE 8 ).

Leg I–IV showed as Figs. 9 View FIGURE 9 . I-L-1 dorsally with four setae ( Figs. 9-A View FIGURE 9 ); I-L-2 ventrally with one long and one short blunt seta, dorsally with six awl-shaped setae; I-L-3 with two ventral blunt setae and four dorsal setae, of which the distal one the longest; I-L-4 with two pairs of blunt setae, anterior setae longer than posterior twos, distally with one short seta; I-L-5 ventrally with five blunt setae, of which the first one the longest and the second the shortest; I-L-6 dorsally with one seta. II-L-1 with four awl-shaped setae ( Figs. 9-B View FIGURE 9 ); II-L-2 with six awl-shaped setae and one subdistal slender blunt setae; II-L-3 with five dorsal setae, one distal short heavy seta and four awlshaped setae, laterally with three setae and ventrally with one swimming seta; II-L-4 with two dorsal awl-shaped setae, laterally with three slender heavy setae and three awl-shaped setae, ventrally with two slender heavy setae; II-L-5 with two ventral and three lateral slender heavy setae; II-L-6 with one dorsomedial long awl-shaped seta. III-L-1 with three dorsal awl-shaped setae and one ventral slender seta ( Figs. 9-C View FIGURE 9 ); III-L-2 with two pairs of dorsal awl-shaped setae and two ventral blunt setae; III-L-3 with three dorsal awl-shaped setae, one ventral blunt seta and one distolateral swimming seta; III-L-4 with three long ventral setae, one lateral heavy seta, three dorsal awlshaped setae and three swimming setae; III-L-5 ventrally with four blunt setae, laterally with two slender heavy setae and three short swimming setae; III-L-6 distally with few fine setae. IV-L-1 dorsally with three awl-shaped setae of which the distal one longer than others ( Figs. 9-D View FIGURE 9 ); IV-L-2 with four dorsal awl-shaped setae and one distal moderate blunt seta, IV-L-3 ventrally with six blunt setae, dorsally with three, laterally with two awl-shaped setae; IV-L-4 ventrally with six unequal blunt setae, distally with two short and three long swimming setae. IV-L-5 ventrally with four blunt setae, dorsally with three awl-shaped setae and distally with three long swimming setae; IV-L-6 ventrally with two moderate blunt setae. Claws of legs II–IV sickle-shaped and each with a short dorsal and a long ventral clawlet ( Figs. 9-F View FIGURE 9 ).

Measurements (n=4). Idiosoma L/W 613/480–627/453 (ratio 1.28–1.38). Genital field L/W 147/177–180/210 (L/W ratio 0.83–0.86). LA 203–210. LP 230–240. Medial distance between Cx-IV 32–36. Ejaculatory complex L 153–157. Chelicera L 120–123. L of P-1–5: 15–18; 83–93; 47–48; 88–93; 60–68. Lengths of I-L-1–6: 63–67; 140– 141; 172–183; 237–240; 170–172; 177–180. Lengths of II-L-1–6: 62–63; 137–163; 193–196; 243–250; 280–285; 227–233. Lengths of III-L-1–6: 60–63; 133–135; 153–190; 183–189; 227–234; 187–190. Lengths of IV-L-1–6: 83–97; 133–137; 177–185; 210–217; 310–317; 280–283.

Male. Integument smooth; posterior dorsal platelets slightly longer than female. Acetabular plates terminally located ( Figs. 7-C View FIGURE 7 ), anteriorly and posteriorly fused by sclerotized cuticle; three anterior acetabula arranged in a triangle, and three posterior acetabula in a row; ten pairs of setae present on genital plate edge (in one specimen, left side with eight and right side with ten), of which three located anteriorly to the first acetabular group, three on the area between the two acetabular groups (including inner two near the second acetabular group), three laterally to and one posteriorly to the second acetabular group; two long setae free from and anterior to genital field.

Measurements (n=3). Idiosoma L/W 607/420–820/680 (ratio 1.20–1.45). Genital field L/W 100/143–113/147 (L/W ratio 0.70–0.80). LA 205–260. LP 230–272. Medial distance between Cx-IV 37–53. Chelicera L 137–150. L of P-1–5: 23–25; 100–118; 48–67; 102–117; 75–80. Lengths of I-L-1–6: 80–90; 173–197; 200–224; 264–297; 170–204; 200–217. Lengths of II-L-1–6: 70–77; 157–200; 207–240; 267–304; 290–329; 250–270. Lengths of III- L-1–6: 70–77; 137–163; 167–210; 190–223; 238–270; 193–227. Lengths of IV-L-1–6: 86–126; 123–180; 190–217; 217–250; 328–374; 290–340.

Remarks. Within the subgenus Unionicola , V 2 gland larger than dorsal glandularia is rare according to the available literature. Generally, gland of V 2 is as large as those of A 1, D 1, L 4, etc. in the known species, like U. crassipes , of the subgenus; II-L-6 dorsally with one long awl-shaped seta, which again is an unusual character differing from other members of the subgenus Unionicola ; the three thick inner setae on acetabular plates are very short and do not reach to acetabula in female in the new species, while they are long and at least overring the margin of adjacent acetabulum in all known members of the subgenus. Although U. (U.) suiyangensis sp. nov. is similar to U. (U.) xishuiensis sp. nov. in the shape of palp, coxae and genital field, they can be distinguished by: (1) Chelicera with one proximal sickle-shaped projection in U. xishuiensis , but normal in U. suiyangensis ; (2) Ventral apodeme of infracapitulum bent as a hook in U. xishuiensis , while it almost straight in U. suiyangensis ; (3) II-L-6 dorsally with one long awl-shaped seta in U. xishuiensis ; but smooth and normal in U. suiyangensis .