Hygrobates intermedius Goldschmidt & Nishikawa & Hiruta & Shimano 2020, sp. nov.
Creators: name: Goldschmidt, Tom
name: Nishikawa, Kanto
name: Hiruta, Shimpei F.
name: Shimano, Satoshi
Publisher: name: Zenodo
Year: 2020
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Trombidiformes
Hygrobatidae
Hygrobates
Hygrobates intermedius

description: Hygrobates intermedius sp. nov. Goldschmidt, Nishikawa & Shimano
Material examined: Holotype male, slide mounted in glycerine jelly, preparation no. CIB INV 0001, parasitic on Paramesotriton qixilingensis (Amphibia, Caudata, Salamandridae): newt was collected in China, Jiangxi Province, Yongxin County, Shenyuan Station; N 26° 46’ 25.2’’, E 114° 10’ 53.7’’, 375m a.s.l. on March 26th 2014, preserved in 70% Ethanol; mite was attached to the fore- or hindlimb of the newt (CIB 140328).
Paratypes: one female CIB INV 0002 from fore- or hindlimb of the newt (CIB 140328), one male CIB INV 0003 from mouth cavity, limbs, or lateral body of the newt (CIB 140327, 29–31, or 33)—newts data are the same as holotype’s host.
Distribution: All three specimens of H. intermedius sp. nov. have been recorded on Paramesotriton qixilingensis. The type locality of the newt (Qixiling Nature Reserve, Mount Shenyuan, Yongxin County, Jiangxi, China) is the only known collecting site for both, the newt and the mite.
Derivatio nominis: intermedius (lat.)—located between, intermediate; named for the fact that most characters of the new species are somehow intermediate between all other species of Lurchibates.
Diagnosis: Characters of the subgenus Lurchibates; anterior coxal group relatively narrow posteriorly (compared to most other species of the subgenus), posterior coxal group triangular; male genital field rounded dumbbell-shaped, regularly surrounded by many setae; female genital plates crescent-shaped, relatively short (flanking only posterior 2/3 of genital opening); palp relatively long and slender, P-3 ventrally with dense field of denticles, P-4 long, straight, proximo-ventral extension of P-5 blunt, cone-shaped; cheliceral claw relatively straight, long and slender.
Description, Male (n = 2): Idiosoma rounded-oval, L/W ratio 1.34 (1.25), L/W 900 (900)/672 (720); fused anterior coxae of both sides slightly elongate (Cx-I + II L/W 294 (310)/462 (439)), medio-posterior margin straight to slightly convex, laterally extended by secondary sclerotization (swallow-tail shaped, lateral tips reaching under medial margin of Cx-III/IV), Cx-I basal W 160 (150); gnathosoma broad, posteriorly only slightly converging, widely fused with the posterior part of the first coxae, anterior margin of gnathosoma curved (Fig. 1); posterior coxal groups (Cx-III + IV of one side) L/W 288 (283)/270 (270), laterally closely approached to anterior plates (Cx- II postero-laterally overlapping antero-lateral corners of Cx-III), medially clearly diverging from anterior coxae, nearly regularly triangular in shape, small, rounded medial edges formed by Cx-IV only, Cx-IV short and broad, nearly triangular, posterior margin straight to slightly convex, medially pointing towards anterior, lateral margin straight to convex (Fig. 1); genital field dumbbell-shaped (Ac-1 and Ac-3 anteriorly and especially posteriorly extending beyond pre- and postgenitale), outline broad-oval (anteriorly and laterally rounded, posteriorly straight), pregenitale nose-shaped, anteriorly extended, genital opening relatively small, elongated egg-shaped, genital field L/W 198 (204)/ 348 (384); Ac-1 elongated oval, Ac-2 irregularly oval, Ac-3 elongated triangular, anteriorly pointed (L/W Ac-1, 104 (100)/54 (51), Ac-2, 118 (107)/51 (54), Ac-3, 113 (116)/77 (64)), 25–28 setae on each side of plate, arranged at the margins of the genital plate (Fig. 1); excretory pore slit-shaped; genital skeleton L/W 223 (252)/183 (181), compact (L/W ratio 1.22 (1.39)), shape typical for the subgenus, brachia distalia long, strong, laterally strongly curved, brachia proximalia strong, distally broadened, parallel to longitudinal axis, (Fig. 2); all legs slender, bearing many heavy setae (Figs. 3–6); measurements (L/H) of distal leg segments: I-leg-5, 252 (248)/54 (48), I-leg-6, 216 (199)/48 (50); II-leg-5, 264 (277)/54 (54), II-leg-6, 228 (240)/48 (49); III-leg-5, 294 (259)/56 (53), III-leg-6, 252 (222)/52 (48); IV-leg-3, 180 (175)/68 (66), IV-leg-5, 300 (306)/49 (54), IV-leg-6, 282 (270)/43 (48); chelicerae very strong, with a relatively short, high basal segment and long basal groove; cheliceral claws very large, slender, sharply pointed, dorsal margin in the distal third with strong serration that continues proximally in a lateral serration, medially and laterally striated (Figs. 7, 8); palps strong (Figs. 9, 10), ventral margin of P-2 slightly concave, antero-ventral margin rounded, without denticles, P-3 ventrally straight with a field of pointed denticles in the distal half, occasionally the distal two thirds, P-4 relatively long and straight, distally slightly curved, with a pair of ventral setae in the distal third; P-5 with a well developed, blunt cone-shaped ventro-proximal projection, dorsodistally P-5 bears one compact, denticle-like distal claw and ventro-distally a pair of similar large, strong, pointed, slightly curved claws; mouthpart measurements: chelicera total L 408 (394), maximum H 102 (96), L/H ratio 4.0 (4.1), basal segment L 259 (244), claw L 198 (190), basal segment/claw ratio 1.3 (1.3); curvation of cheliceral claw 21° (20°), palp total L 486 (493), L/H P-1, 47 (45)/63 (68), P-2, 129 (134)/81 (80), P-3, 94 (94)/75 (75), P-4, 169 (173)/56 (56), P-5, 47 (47)/45 (47).
Description, Female (n = 1): Idiosoma similar to male, much larger, L/W 1824/1464, and more rounded (L/W ratio 1.25); unpaired anterior coxal group slightly more compact, basally broader than in males (Cx-I + II L/W 408/589), basal width Cx-I 211; medio- and latero-posterior margin extended by secondary sclerotization, Cx-I latero-posteriorly with apodemes similar to those in males, however more hook-shaped; gnathosoma broadly fused with the posterior part of the first coxae, lateral margins straight, nearly parallel, coxal groups further separated than in males, medially heavily diverging (Fig. 11); paired posterior coxal groups well distanced from each other and from the anterior coxal group, L/W 356/320, roughly triangular in shape with medial edges only slightly diverging from longitudinal axis, postero-medial corner less pointed, medial margin formed by Cx-IV and Cx-III (Fig. 11); genital field far distant from coxae, rather small, with strongly sclerotized pre- and postgenitale, genital plates well distant from each other, separated by soft integument, slightly kidney-shaped, anteriorly rounded, flanking posterior 2/3 of genital opening, total genital field L/W 312/420; acetabula irregularly-oval (L/W Ac-1, 83/54, Ac- 2, 109/54, Ac-3, 101/58); 20/22 setae arranged mainly at the anterior, posterior and lateral margins of the genital plates, two, respectively three, setae anterior to genital plates (Fig. 11); legs similar to males, slightly more slender (Figs. 12–15); measurements of distal leg segments: L/H I-leg-5, 276/54, I-leg-6, 276/54; II-leg-5, 294/54, II-leg-6, 257/54; III-leg-5, 324/60, III-leg-6, 282/53; IV-leg-3, 228/85, IV-leg-5, 354/60, IV-leg-6, 312/48; anterior margin of the gnathosoma by far more projecting than in males, anterior half completely separated from Cx-I (Fig. 11); chelicerae similar to males, slightly more compact (Figs. 16, 17); palps similar to males (Figs. 18, 19); mouthpart measurements: chelicera total L 456, maximum H 126, L/H ratio 3.6, basal segment L 282, claw L 221, basal segment/claw ratio 1.3; cheliceral claw curve 21°; palp total L 550, L/H P-1, 54/78, P-2, 150/94, P-3, 110/85, P-4, 188/62, P-5, 47/49.
description: Published as part of Goldschmidt, Tom, Nishikawa, Kanto, Hiruta, Shimpei F. & Shimano, Satoshi, 2020, Description of three new water mite species of Hygrobates Koch, 1837 (Lurchibates Goldschmidt & Fu, 2011) (Acari, Hydrachnidia, Hygrobatidae), parasitic in newts of the genera Paramesotriton and Pachytriton (Amphibia, Caudata, Salamandridae) from China, pp. 25-42 in Zootaxa 4768 (1) on pages 27-31, DOI: 10.11646/zootaxa.4768.1.3, http://zenodo.org/record/3777804