Torrenticola multiserrater 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 : 132-134

Torrenticola multiserrater Gu & Guo sp. nov. ( Figures 1–4 )

Type Materials. Holotype male: No. CQ-TO-2022081101, China, Chongqing, Wuxi County, 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 . Paratypes: 1/3/0, No. CQ-TO-2022081102 –CQ-TO-2022081105, same data as holotype.

Diagnosis. Dorsal plate arrangement: 4+1; P-2 with five dorsal setae, a jagged serrated extension on ventrum, and one ventral seta at the base of ventral extension; P-3 with an obvious serrated terminal-margin, one serrated ventral extension, and three dorsal and one ventral setae.

Description. Male (n = 2): Idiosoma elliptical, L 733 (730), W 442 (432), L/W ratio 1.66 (1.69). Dorsal plate arrangement: 4+1 ( Fig. 1A ); dorsal shied L 598 (576), W 392 (385), dorsal plate L 532 (519), frontal platelets L 150 (122), W 60 (65), shoulder platelets L 180 (177), W 70 (70). Infracapitular bay V-shaped, L 121 (117); Cx-I L 246 (235), mL 126 (120), Cx-II+III mL 117 (127); genital field elliptical, L 138 (129), W 101 (97); C 4 at the same level as the 4 th pair of acetabula; V 1 anterior to V 2, V 2 almost at the same level of Ap ( Fig. 1B ). Gnathosoma: dL 218 (225), vL 299 (305); rostrum long and dorsal apodeme short and blunt, ventral apodeme long and blunt; chelicera bs L 302 (301), claw L 43 (44) ( Fig. 1D ). Palp ( Fig. 1C ): P-1 short, with one dorsodistal seta; P-2 with five dorsal setae, and one ventral seta at the base of a jagged serrated extension; P-3 with an obvious serrated terminal-margin, one serrated ventral extension, and three dorsal and one ventral setae; P-4 with one thin dorsal seta and three ventral setae on two ventral extensions. L of palp segments: P-1, 31 (28); P-2, 78 (79); P-3, 52 (55); P-4, 115 (101); P-5, 14 (13). Legs ( Fig. 2 ): L of leg segments: I-L-1–6: 30 (29), 54 (59), 62 (63), 71 (73), 85 (92), 86 (93); II-L-1–6: 28 (30), 70 (78), 54 (59), 69 (74), 78 (80), 67 (86); III-L-1–6: 34 (37), 82 (81), 57 (58), 79 (82), 92 (99), 92 (100); IV-L-1–6: 88 (91), 97 (94), 88 (98), 110 (120), 121 (128), 110 (114). Ejaculatory complex ( Fig. 1E ), L 158 (148), aL 105 (-).

Female (n = 3). Body features same as the male except genital field pentagonal ( Fig. 3B ). Idiosoma L 753 (725–753), W 464 (449–464), L/W ratio 1.6 (1.61–1.62). Dorsal shield L 607 (600–607), W 399 (399–409), L/W ratio 1.5 (1.48–1.52); dorsal plate L 543 (534–543), frontal platelets L 134 (134–148), W 53 (53–61), L/W ratio 2.5 (2.4–2.5). Infracapitular bay depth 132 (124–132); Cx-I L 258 (254–258), mL 123 (123–129), Cx-II + III mL 97 (97–103). Genital field L 156 (156–157), W 138 (138–140), L/W ratio 1.11 (1.11–1.13); distance between genital field and Ap 175 (164–175). Gnathosoma vL 323 (297–323), dL 231 (231–268), chelicera bs L 315 (315–335), claw L 45 (40–45). L of palp: P-1, 30 (30–32); P-2, 83 (81–83); P-3, 53 (53–58); P-4, 93 (88–93); P-5, 14 (13–14). L of leg segments: I-L-1–6: 32 (32–34), 76 (76–81), 62 (62–65), 76 (76–79), 86 (87–96), 87 (87–97); II-L-1–6: 31 (31–34), 76 (75–76), 59 (59–60), 69 (69–72), 80 (80–85), 84 (84–85); III-L-1–6: 35 (32–35), 86 (67–86), 59 (59–61), 87 (84–87), 98 (94–98), 88 (88–94); IV-L-1–6: 90 (90–97), 101 (97–101), 96 (96–101), 120 (117–120), 129 (123–129), 104 (104–116).

Habitat. Streamlet, about 0.3–0.5 m in depth, with many small stones at the bottom.

Remarks. Plap with serrated ventral extensions was also found in a small number of torrenticolid mites, such as T. dentifera Wiles, 1991 ( Gu et al. 2020b), T. dentipalpis Jin, 1997 ( Jin 1997) , T. alargada Goldschmidt, 2007 ( Goldschmidt 2007) and T. turkestanica (Sokolow, 1926) ( Pešić & Smit 2009) . However, the aforementioned torrenticolid mites only have a regular (rod-shaped or rectangular) ventral extension on P-2. T. multiserrater Gu & Guo sp. nov., can be distinguished from other members of the genus by P-2 with a jagged serrated extension on ventrum, which like a flower cluster or coral, and one ventral seta at the base of ventral extension; P-3 with an obvious serrated terminal-margin, one serrated ventral extension, and three dorsal setae and one ventral seta ( Figs. 1C , 3C ).

Etymology. The specific name, multiserrater , is a combination from the Latin words: “ multi- ” and “ serrated ”, referring to this species having multiple serrated extensions, forming a jagged serrated extension on ventrum ( Figs. 1C , 3C ); used as a noun in apposition.

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

Figures

FIGURE 1. Torrenticola multiserrater 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 2. Torrenticola multiserrater 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 3. Torrenticola multiserrater Gu & Guo sp. nov., female: A = dorsal view; B = ventral view; C = palp; D = infracapitulum and chelicera. Scale bars = 100 μm.

FIGURE 4. Torrenticola multiserrater Gu & Guo sp. nov., female: A = Leg-I; B = Leg-II; C = Leg-III; D = Leg-IV-1–3; E = Leg-IV-4–6. Scale bars = 100 μm.