Torrenticola sabahensis, Pešić & Smit, 2014

Pešić, Vladimir & Smit, Harry, 2014, Torrenticolid water mites (Acari: Hydrachnidia: Torrenticolidae) from Malaysian Borneo, Zootaxa 3840 (1), pp. 1-72 : 11-13

Torrenticola sabahensis n. sp.

( Figs. 6A–E , 7A–B , 9G–I , 10G–I , 23D )

Type series. Holotype male, dissected and slide mounted, Malaysia, Borneo , Great Lumotok stream, Mt Kinabalu, 6º09.336 N, 116º08.417 E, alt. 433 m asl., 18.ix.2012 Smit . Paratypes: one juvenile male, one female, same data as holotype, female dissected and slide mounted .

Further records. Malaysia, Borneo : Little Lumotok stream, Sayap, 6º09.497 N, 116º34.027 E, alt. 1065 m asl., 17.ix.2012 Smit 6/1/0 (1/0/0 mounted); Mahua stream, Mahua, Crocker Range, 5º47.838 N, 116º24.510 E, alt. 1052 m asl., 21.ix.2012 Smit 1/1/0; first stream Minduk Sirung Trail, Alab, Crocker Range, 5º45.225 N, 116º26.085 E, alt. 752 m asl., 22.ix.2012 Smit 0/1/0 .

Diagnosis. Idiosoma elongated-oval (dorsal shield L/W ratio 1.3–1.4); shoulder platelets fused to the large dorsal plate; dorsal shield without colour pattern; Cxgl–4 anteriorly adjacent to Cxgl–2, posterior at margin of CxI/II; suture lines of Cx-IV extending posteriorly beyond posterior margin of genital field; excretory pore on the level with Vgl–2. Male: medial suture line of Cx-II+III moderately long.

Description

General features —Idiosoma elongated-oval; shoulder platelets fused to the large dorsal plate; dorsal shield without colour pattern ( Figs. 9G–I ); gnathosomal bay U-shaped; Cxgl–4 anteriorly adjacent to Cxgl–2, posterior at margin of Cx-I/II; suture lines of Cx-IV extending posteriorly beyond posterior margin of genital field, laterally curved; excretory and Vgl–2 pore away from the line of primary sclerotization, excretory pore on the level with Vgl–2; gnathosoma with curved ventral margin ( Fig. 6E ); P-2 nearly equal in length as P-4, P-2 ventral margin concave, P-2 ventrodistal protrusion bluntly pointed, curved towards distal; P-3 ventrodistal protrusion pointed and cone-shaped; P-4 with well developed ventral protuberances, ending in two tips separated by a concavity ( Figs. 6D , 7B ). Male: medial suture line of Cx-II+III moderately long; genital field subrectangular in shape; ejaculatory complex conventional in shape ( Figs. 6C , 23D ). Female: genital field pentagonal in shape.

Measurements

Male (holotype, in parentheses specimen from Little Lumotok stream)—Idiosoma (ventral view: Figs. 6B , 10G–H ) L 678 (672), W 481 (478); dorsal shield ( Figs. 6A , 9G–H ) L 556 (539), W 405 (411), L/W ratio 1.37 (1.31); dorsal plate L 519 (503); frontal plate L 143 (144), W 50 (50–53), L/W ratio 2.9 (2.7–2.9). Gnathosomal bay L 131 (148), Cx-I total L 250 (272), Cx-I mL 119 (122), Cx-II+III mL 106 (94); ratio Cx-I L/Cx-II+III mL 2.36 (2.9); Cx-I mL/Cx-II+III mL 1.12 (1.3). Genital field L/W 130 (131)/107 (109), ratio 1.2 (1.2); ejaculatory complex L 162 (149); distance genital field-excretory pore 125 (109), genital field-caudal idiosoma margin 192 (173). Gnathosoma vL 303 (306); chelicera total L 378 (351); palp total L 300–301 (302), dL/H, dL/H ratio: P-1, 37/31, 1.2 (44/34, 1.29); P-2, 92/48, 1.94 (92/48, 1.92); P-3, 59–60/42, 1.42 (57/45, 1.28); P-4, 94/30, 3.1 (89/31, 2.9); P-5, 18/16, 1.1 (20/15, 1.3); P-2/P-4 ratio 0.98 (1.03).

Female (paratype from Great Lumotok stream)—Idiosoma (ventral view: Figs. 7A , 10I ) L 755, W 559; dorsal shield ( Fig. 9I ) L 616, W 469, L/W ratio 1.31; dorsal plate L 575; frontal plate L 152–155, W 56, L/W ratio 2.7–2.8. Gnathosomal bay L 172, Cx-I total L 305, Cx-I mL 133, Cx-II+III mL 73; ratio Cx-I L/Cx-II+III mL 4.2; Cx-I mL/Cx-II+III mL 1.8. Genital field L/W 156/146, ratio 1.07; distance genital field-excretory pore 144, genital field-caudal idiosoma margin 220. Gnathosoma vL 363; chelicera total L 450; palp total L 351–352, dL/H, dL/H ratio: P-1, 51/38, 1.3; P-2, 111/57, 1.95; P-3, 68-69/48, 1.44; P-4, 103/32, 3.2; P-5, 18/17, 1.06; P-2/P-4 ratio 1.07.

Etymology. Named after the province (Sabah) where the new species was found.

Discussion. The new species is most similar to Torrenticola longipalpis Wiles, 1997 (see below). The latter species can easily be separated from T. sabahensis n. sp. due to the less slender idiosoma, the characteristic colour pattern (see Figs. 9E–F ), Cxgl–4 shifted more anteriorly, at margin of Cx-I/II, the longer ventral seta on P-2, and in males, medial suture line of Cx-II+III shorter and suture lines of Cx-IV extending less posteriorly beyond posterior margin of genital field.

Habitat. Sandy/bouldery streams, shaded by rain forest ( Fig. 43A ).

Distribution. Borneo.

Figures

FIGURE 6A–E. Torrenticola sabahensis n. sp., holotype male, Great Lumotok stream: A = dorsal shield; B = idiosoma, ventral view; C = ejaculatory complex; D = palp, lateral view (P-1 lacking); E = gnathosoma. Scale bars = 100 µm.

FIGURE 7A–B. Torrenticola sabahensis n. sp., female, Great Lumotok stream: A = idiosoma, ventral view; B = palp, medial view. Scale bars = 100 µm.

FIGURE 9A–I. Photographs of dorsal shield. A–B Torrenticola borneoensis n. sp., Kemantis stream: A = male holotype; B = female paratype. C–D T. kinabaluensis n. sp.: C = male holotype; D = female paratype, Little Lumotok stream. E–F T. longipalpis Wiles, 1997, male, Mahua stream. G–I T. sabahensis n. sp.: G = male holotype; H = male, Little Lumotok stream; I = female paratype, Great Lumotok stream.

FIGURE 10A–I. Photographs of ventral shield. A–B Torrenticola borneoensis n. sp., Kemantis stream: A = male holotype; B = female paratype. C–E T. kinabaluensis n. sp.: C = male holotype; D = male paratype, Little Lumotok stream; E = female paratype, Little Lumotok stream. F T. longipalpis Wiles, 1997, male, Mahua stream. G–I T. sabahensis n. sp.: G = male holotype; H = male, Little Lumotok stream; I = female paratype, Great Lumotok stream.

FIGURE 23A–H. Photographs of ejaculatory complex. A Torrenticola borneoensis n. sp. B T. kinabaluensis n. sp.. C T. longipalpis Wiles, 1997. D T. sabahensis n. sp. E Torrenticola minuta (Lundblad, 1941). F T. neoindica n. sp. G Neoatractides uniscutatus n. sp. H Pseudotorrenticola borneoensis n. sp.

FIGURE 43A–D. Photographs of selected sampling sites: A—Mahua stream (type locality of Torrenticola kinabaluensis n. sp. and sampling site of Torrenticola borneoensis n. sp., T. sabahensis n. sp., T. minuta, T. neoindica n. sp., T. cf. pugionirostris, Monatractides longiventris, M. parviventris and M. morpheus n. sp.), B—Unnamed stream Bansadon Trail (type locality of Neoatractides uniscutatus n. sp. and sampling site of Torrenticola borneoensis n. sp., T. kinabaluensis n. sp., Monatractides cf. macroporus and M. parviventris). C—Kibamabangan River (type locality of Torrenticola schilthuizeni n. sp. and sampling site of Torrenticola borneoensis n. sp., T. kinabaluensis n. sp., T. minuta and T. neoindica n. sp., Monatractides cf. macroporus, M. oxystomus, M. parviventris and M. morpheus n. sp.). D—Kemantis stream (type locality of Torrenticola borneoensis n. sp., Neoatractides sundaensis n. sp. and Monatractides phantasos n. sp. and sampling site of T. minuta, Monatractides longiventris, M. parviventris and M. morpheus n. sp.). Photos. H. Smit.