Torrenticola (Megapalpis)

Jia, Lan, Gu, Xinyao, Jin, Daochao & Guo, Jianjun, 2023, A newly recorded and a new species of torrenticolid mites (Acari: Hydrachnidiae) from China, Zoological Systematics 48 (1), pp. 100-105 : 104-105

Torrenticola (Megapalpis) distans K.O. Viets, 1981 ( Figs 3–4 )

Description. Male (n = 1). Idiosoma elliptical, and flattened, L 765, W 487, L/W ratio 1.6 ( Fig. 3A ). Dorsal shied L 689, W 415, L/W ratio 1.7; frontal platelet proximately rectangular, L 114, W 61, L/W ratio 1.8; shoulder platelets approximately triangular, L 225, W 76, L/W ratio 3.0 ( Fig. 3A ). Infracapitular bay U-shaped, deep and wide, L 213. Cx-I L 339, mL 126, Cx-II–III mL 114. Gf small and rectangular, L 129, W 110, L/W ratio 1.2. E 4 aligned with acetabula pair III ( Fig. 3B ); distance between Gf and Ap 194. Cx-IV trailing edge pronounced, V 1 anterior to trailing edge of Cx-IV, V 2 located on the trailing edge of Cx-IV, V 2 almost at same level of Ap ( Fig. 3B ). Gnathosoma dL 238, vL 320, claw L 160, chelicera bs L 290, ventral processes almost absent, dorsal processes short and slightly pointed at end, rostrum long and curved upwards, and with fine setae at end ( Fig. 3D ). Palp ( Fig. 3C ): P-1 with one short dorsal seta; P-2 with four short dorsal setae, one ventral seta on the upper middle of processes; P-3 with one seta on middle of dorsum, one ventral seta; both P-2 and P-3 without ventral processes; P-4 slender, with one slender dorsal seta, ventral surface with two extensions, each of them with a slender seta. L of palp segments ( Fig. 3C ): P-1, 42; P-2, 152; P-3, 67; P-4, 143; P-5, 32. L of legs ( Figs 3E–F ): I-L-1–6: 85, 152, 164, 173, 182, 148; IV-L-1–6: 158, 182, 165, 206, 251, 217.

Female (n = 1). Body features same as male except: Idiosoma L 906, W 594, L/W ratio 1.5 ( Fig. 4A ). Dorsal shield L 803, dorsal plate L 750, W 495, L/W ratio 1.5. Frontal platelets L 137, W 68, L/W ratio 2.0. Shoulder platelets L 225, W 76, L/W ratio 3.0 ( Fig. 4A ). Infracapitular bay L 213. Cx-I L 304, mL 110, Cx-II–III mL short, L 19. Gf L 209, W 175, L/W ratio 1.2 ( Fig. 4B ). Distance between Gf and Ap 266. E 4 aligned with acetabula pair V. Ap located at posterior edge ofsecondary ossification line; Gnathosoma vL 398, dL 285, chelicera bs L 294, claw L 186 ( Fig. 4D ). L of palp segments ( Fig. 4C ): P-1, 44; P-2, 19; P-3, 91; P-4, 175; P-5, 38. L of legs: I-L-3-6: 148-167-198-145.

Material examined. 1♂ 1♀, No. JX-TO-2009080401—02, Huangbitan River , Wuyishan National Nature Reserve , Yanshan, Shangrao, Jiangxi, China (27°50′53′′N, 117°43′43′′E, elev. 916 m), 4.VIII.2009, coll. Hao Zhong.

Habitat. Streams, running water, with mayflies, small fish and no water plants.

Distribution. China (Jiangxi), South Africa (K.O. Viets 1981).

Remarks. The species is recorded in China for the first time. The population in China is almost identical to the South African population (Viets, 1981) except P-2 with four/three dorsal setae in male/female rather than only one dorsal seta as the drawing of the South African specimen.

Funding This research was supported by SRT program of Guizhou University ((2019) 337), National Natural Science Foundation of China (31772421) and Guizhou Provincial Science and Technology Projects (Qiankehe Pingtai Rencai-GCC [2022]029-1) .

Acknowledgements Special thanks are given to Hao Zhong (Institute of Entomology, Guizhou University, China) and Xu Zhang (College of Life Sciences, Huaibei Normal University, China) for the collections of the specimens.

Figures

Figure 3. Torrenticola (Megapalpis) distans K.O. Viets, 1981, male. A. Dorsal view; B. Ventral view; C. Palp; D. Infracapitulum and chelicera; E. Leg-I; F. Leg-IV. Scale bars=100μm.

Figure 4. Torrenticola (Megapalpis) distans K.O. Viets, 1981, female. A. Dorsal view; B. Ventral view; C. Palp; D. Infracapitulum and chelicera. Scale bars=100μm.