Torrenticola pseudoalargada Gu & Guo, 2023

Gu, Xinyao, Zhang, Yuhao, Zheng, Yuling & Guo, Jianjun, 2023, First collection of Torrenticolidae (Hydrachnidiae, Acari) from Yintiaoling National Nature Reserve, China, with descriptions of two new species, Zootaxa 5257 (1), pp. 131-142 : 136-138

Torrenticola pseudoalargada Gu & Guo sp. nov. ( Figures 5–8 )

Type Materials. Holotype male: No. CQ-TO-2022081301, China, Chongqing, Wuxi, Yintiaoling National Nature Reserve, Lanying Grand Canyon (31°26′19′′N, 109°50′46′′E, 870 m a.s.l.), collected by Yuhao Zhang, 13-VIII- 2022 . Paratypes: 1/3/0, No. CQ-TO-2022081106 – CQ-TO-2022081109, Yintiaoling National Nature Reserve , Linkouzi (31°28′35′′N, 109°53′18′′E, 1250 m a.s.l.), collected by Yuhao Zhang, 11-VIII-2022 .

Diagnosis. Dorsal plate arrangement: 4+1; Infracapitular bay U-shaped; P-2 with four dorsal setae, and one ventral seta at the base of a serrated extension; P-3 with one serrated rectangular extension on ventrum, at the base of which with one ventral seta; P-4 with two dorsal setae, and two setae on two ventral extensions.

Description. Male (n = 2): Idiosoma elliptical, L 690 (813), W 438 (538), L/W ratio 1.6 (1.5). Dorsal plate arrangement: 4+1 ( Fig. 5A ); dorsal shied L 558 (626), W 391 (467), dorsal plate L 526 (571), frontal platelets L 118 (129), W 53 (65), L/W ratio 2.2 (2.0); shoulder platelets L 169 (202), W 61 (85), L/W ratio 2.8 (2.4). Infracapitular bay U-shaped, L 131 (156); Cx-I L 256 (300), mL 126 (144), Cx-II+III mL 78 (112); genital field ellipse, L 152 (185), W 106 (140); C 4 at the same level as the 4 th pair of acetabula; the posterior margin of Cx-IV relatively indistinct; V 1 anterior to V 2, V 2 almost at the same level of Ap ( Fig. 5B ). Gnathosoma: dL 206 (266), vL 281 (350); rostrum long and dorsal apodeme short, ventral apodeme long and blunt; chelicera bs L 281 (356), claw L 41 (47), ( Fig. 5D ). Palp ( Fig. 5C ): P-1 short, with one dorsodistal seta; P-2 with four dorsal setae, and one ventral seta at the base of a serrated extension; P-3 with two dorsal setae and one serrated rectangular extension on ventrum, at the base of which with one ventral seta; P-4 with two dorsal setae, and two ventral setae on two ventral extensions. L of palp segments: P-1, 30 (39); P-2, 85 (105); P-3, 52 (55); P-4, 63 (70); P-5, 15 (19). Legs ( Fig. 6 ): L of leg segments: I-L-1–6: 33 (36), 78 (84), 66 (72), 70 (88), 79 (97), 80 (91); II-L-1–6: 31 (36), 77 (89), 57 (69), 79 (83), 87 (99), 94 (101); III-L-1–6: 45 (42), 78 (94), 65 (72), 90 (101), 106 (118), 108 (117); IV-L-1–6: 89 (98), 87 (104), 95 (116), 124 (133), 136 (137), 123 (131). Ejaculatory complex ( Fig. 5E ), L 156 (-), aL 118 (-).

Female (n = 3). Body features same as the male except: genital field pentagonal; C 4 at the same level as the 4 th pair of acetabula; the posterior margin of Cx-IV relatively obvious ( Fig. 7B ); P-3 with three dorsal setae ( Fig. 7C ). Idiosoma L 937 (771–937), W 627 (502–627), L/W ratio 1.49 (1.49–1.54). Dorsal shield L 738 (621–738), W 556 (453–556), L/W ratio 1.3 (1.3–1.4); dorsal plate L 675 (568–675), frontal platelets L 178 (130–178), W 71 (57–71), L/W ratio 2.5 (2.3–2.5), shoulder platelets L 218 (171–218), W 90 (60–90). Infracapitular bay depth 174 (153–174); Cx-I L 348 (293–348), mL 171 (142–171), Cx-II + III mL 76 (48–76). Genital field L 191 (161–191), W 178 (134–178), L/W ratio 1.1 (1.1–1.2); distance between genital field and Ap 202 (177–202). Gnathosoma vL 412 (308–412), dL 309 (231–309), chelicera bs L 433 (330–433), claw L 53 (51–53). L of palp: P-1, 43 (34–43); P-2, 125 (95–125); P-3, 66 (55–66); P-4, 81 (66–81); P-5, 13 (13–17). L of leg segments: I-L-1–6: 43 (30–43), 100 (85–100), 85 (70–85), 94 (76–94), 112 (81–112), 101 (81–101); II-L-1–6: 40 (34–40), 96 (85–96), 79 (64–79), 99 (83–99), 114 (88–114), 112 (99–112); III-L-1–6: 40 (35–40), 108 (83–108), 85 (69–85), 122 (98–122), 139 (115– 139), 129 (122–129); IV-L-1–6: 120 (101–120), 102 (102–118), 122 (113–122), 157 (132–157), 159 (143–159), 144 (139–144).

Habitat. Streamlet, about 0.3–0.5 m in depth, is so clear that you can see many small stones at the bottom.

Remarks. The present species is similar to T. alargada Goldschmidt, 2007 , a species from Latin American ( Goldschmidt 2007). Both species have a serrated ventral extension on P-2, two setae-bearing projections on ventral margin of P4, and a similar gnathosoma. The new species differs from T. alargada in: (1) T. pseudoalargada Gu & Guo sp. nov. with a U-shaped infracapitular bay, but V-shaped in T. alargada ; (2) T. pseudoalargada Gu & Guo sp. nov. without color pattern, but posterior two-thirds of dorsal plate red to pale reddish in T. alargada ; (3) P-4 with two ventral setae in T. pseudoalargada Gu & Guo sp. nov., but with four ventral setae in T. alargada .

In addition, the new species resembles T. malaisei (Lundblad, 1941) ( Wiles 1997; Pešić et al. 2012) in: P-3 with a short, subrectangular, apically serrated ventrodistal projection, and a long seta laterally at the base of the projection and a comparatively short P-4. But two species have obvious differences in: (1) P-2 with a flat blade-like ventral extension in T. malaisei but with a serrated extension in T. pseudoalargada ; (2) posterior suture line of Cx-IV obvious and long in T. malaisei but retrogressive in T. pseudoalargada ; (3) Cx-I –II exceeding to the anterior margin of idiosoma in T. malaisei , but only Cx-I and Cx-II exceeding to it in T. pseudoalargada .

Etymology. This species is named after its similar species, T. alargada . And the specific name, pseudoalargada , is from the Latin affix: “ pseudo -”, which means fake or simulated; used as a noun in apposition.

Distribution. Known only on the type locality (Wuxi, Chongqing of China).

Figures

FIGURE 5. Torrenticola pseudoalargada Gu & Guo sp. nov., male:A = dorsal view; B = ventral view; C = palp; D = infracapitulum and chelicera; E = Ejaculatory complex. Scale bars = 100 μm.

FIGURE 6. Torrenticola pseudoalargada Gu & Guo sp. nov., male: A = Leg-I; B = Leg-II; C = Leg-III; D = Leg-IV-1–4; E = Leg-IV-5, 6. Scale bars = 100 μm.

FIGURE 7. Torrenticola pseudoalargada Gu & Guo sp. nov., female:A = dorsal view; B = ventral view; C = palp; D = infracapitulum and chelicera. Scale bars = 100 μm.

FIGURE 8. Torrenticola pseudoalargada Gu & Guo sp. nov., female: A =Leg-I; B = Leg-II; C = Leg-III; D = Leg-IV-1–4; E = Leg-IV-5, 6. Scale bars = 100 μm.