Torrenticola songhuaensis, Gu & Jia & Jin & Guo, 2020

Gu, Xinyao, Jia, Lan, Jin, Daochao & Guo, Jianjun, 2020, Four new species of Torrenticola (Acari, Hydrachnidia, Torrenticolidae) from Northeastern China, Zootaxa 4779 (2), pp. 245-259 : 250-253

Torrenticola songhuaensis sp. nov.

( Figs. 5–6 )

Material examined. Holotype female, No. JL-TO-20190704, Songhuajiangsanhu National Nature Reserve ( LJAE ỨĀOiDZğȐŊ ṂṚṔṈ), Jilin Province, P. R. China (42°32′34′′N, 127°38′12′′E, 713 m a.s.l.), collected by Zhuhui Ding and Caiyun Li, 30-VII-2019 . Paratype: 0/1/0, No. JL-TO-20190705, same data as holotype.

Diagnosis. Dorsal plate arrangement: 2+2p+1; E 4 on the same line with the 6 th pair of acetabula; V 1 anterior to V 2, Ap between V 2 and V 1; the posterior margin of gnathosoma straight; rostrum short and straight, dorsal apodeme short, ventral apodeme long and sharp.

Description. Female (n = 2): Idiosoma elliptical, L 774 (730), W 556 (519), L/W ratio 1.4 (1.4). Dorsal plate arrangement: 2+2p+1 ( Fig. 5A ), the posterior half of the dorsal plate reddish; dorsal shied L 639 (614), W 484 (461), dorsal plate L 593 (566), frontal platelets L 138 (132), W 63 (58), shoulder platelets W 73 (45). Infracapitular bay U-shaped, L 163 (156); Cx-I L 270 (268), mL 106 (110), Cx-II+III mL 61 (45); Gf L 176 (159), W 158 (145); E 4 on the same line with the 6 th pair of acetabula; V 1 anterior to V 2, Ap between V 2 and V 1; distance between Gf and Ap 170 (178). Gnathosoma: dL 214 (212), vL 299 (281), posterior margin straight; rostrum short and straight, dorsal apodeme short, ventral apodeme long and sharp; chelicera bs L 329 (305), claw L 33 (35) ( Fig. 5D ). Palp ( Fig. 5C ): P-1 short, with one long dorsodistal seta; P-2 long and wide, with three dorsal setae and one ventral extension, one short seta laterally at the base of the extension; P-3 with one long dorsal seta, and one short seta on the ventral prolongation; P-4 with one short dorsal seta and one small ventral extension, on which with one long and two short setae. L of palp segments: P-1, 35 (32); P-2, 96 (98); P-3, 59 (54); P-4, 95 (87); P-5, 20 (18). Legs ( Fig. 6 ): L of leg segments: I-L-1–6: 49 (41), 83 (85), 78 (72), 93 (81), 105 (96), 89 (98); II-L-1–6:, 50 (55), 97 (87), 72 (67), 93 (88), 114 (106), 98 (114); III-L-1–6: 55 (-), 96 (98), 83 (79), 115 (109), 129 (125), 137 (131); IV-L-1–6: 99 (106), 124 (95), 121 (109), 144 (139), 155 (142), 164 (130).

Male. Unknown.

Habitat. Streamlet, about 4 m wide, 0.3–0.5 m depth, with many small stones at the bottom and opulent sunlight; water is cold.

Remarks. This new species is distinguished by the straight posterior margin of gnathosoma. Due to this characters, this new species resembles Torrenticola bomiensis Cook, 1966 ( Pešić & Smit 2014). The new species differs from T. bomiensis in: (1) the posterior half of the dorsal plate reddish in this new species, but without obvious color on the dorsal palte in T. bomiensis ; (2) dorsal plate arrangement 2+2p+ 1 in this new species, but 4+ 1 in T. bomiensis ; (3) the extension of P-2, 3 sharp and smooth in this new species, but blunt and serrated in T. bomiensis .

In addition, Torrenticola songhuaensis is similar to Torrenticola triextensio in the shape of dorsal plate and gnathosoma. But two species have obvious differences in: (1) P-4 with three ventral extensions in T. triextensio , and with two in T. songhuaensis ; (2) T. triextensio is with no obvious color on the dorsal palte, but the posterior half of the dorsal plate reddish in T. songhuaensis ; (3) the posterior margin of gnathosoma pitched in T. triextensio , straight (perpendicular to ventral apodeme) in T. songhuaensis ; (4) the ventral extensions of P-2, 3 in T. triextensio is stouter than T. songhuaensis .

Etymology. This new species is named after the place (Songhua River), where the new species was collected.

Distribution. China (Jilin).

Figures

FIGURE 5. Torrenticola songhuaensis sp. nov. female: A = dorsal view; B = ventral view; C = palp; D = infracapitulum and chelicera; E = close up of the posterior margin of gnathosoma. Scale bars = 100 μm.

FIGURE 6. Torrenticola songhuaensis 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.