Hygrobates (Lurchibates) incognitus, Goldschmidt & Nishikawa & Hiruta & Pfingstl & Jiang & Shimano, 2021

Goldschmidt, Tom, Nishikawa, Kanto, Hiruta, Shimpei F., Pfingstl, Tobias, Jiang, Jian-Ping & Shimano, Satoshi, 2021, Systematics, distribution and morphology of the newt parasitic water mites of the subgenus Lurchibates Goldschmidt & Fu, 2011 (Acari, Hydrachnidia Hygrobatidae, Hygrobates Koch, 1837), including the description of four new species and a key to all so far known species, Zootaxa 4985 (1), pp. 1-36 : 11

Hygrobates (Lurchibates) incognitus sp. nov. Goldschmidt, Nishikawa & Shimano

Material examined: Holotype female, slide mounted in glycerine jelly, preparation no. CIB INV 0023, parasitic on Paramesotriton guangxiensis ( Amphibia, Caudata , Salamandridae ); newt was collected in China, Guangxi Zhuang Autonomous Region, Ningming (mites were collected from unnumbered voucher specimens stored in the CIB collection, without detailed geographic information), preserved in 70% ethanol; mite was attached to the axilla and groin of the newt ( CIB 200404064).

Paratypes: Two females CIB INV 0024 , same newt specimen than holotype; CIB INV 0025 , same collecting data, different newt specimen ( CIB 200404060 ) .

Distribution: All specimens of H. (L.) incognitus sp. nov. were collected from Paramesotriton guangxiensis . The new species is probably limited to the same distribution as its host (southern Guangxi, China and northeastern Cao Bang Province, Vietnam ( Frost 2021)).

Derivatio nominis: incognitus (Latin = unknown, not visible, unexpected); referring to the fact that this species in the molecular analysis (28S) could not be separated from macrochela sp. nov..

Diagnosis: Coxal field relatively broad; gnathosoma anterior heavily curved; female genital plates broad kidney-shaped, flanking posterior 4/5 of genital opening; P-4 relatively slender, proximo-ventral extension of P-5 large, blunt cone-shaped; cheliceral claw relatively curved, slender.

Description, Male: Unknown.

Description, Female (n = 3): Idiosoma rounded-oval, L/W ratio 1.43 (1.40), L/W 1680 (1344)/1176 (960); fused anterior coxae of both sides elongated, triangular, Cx-I + II L/W 432 (360–400)/636 (564–582), ratio 0.68 (0.62–0.71), medio-posterior margin only slightly extended by secondary sclerotization, posteriorly convex, lateral extension straight, pointing postero-laterally, Cx-I basal width 228 (209–212); gnathosoma anteriorly heavily curved, broad, rounded tips far projecting, lateral margin with Cx-I posteriorly clearly converging ( Fig. 30 ); anterior and posterior coxal groups laterally clearly separated, medially diverging; posterior coxae far separated, inclined heart-shaped, antero-medial margin curved, medial edges nose-shaped projecting, formed by Cx-IV only, Cx-IV nearly rectangular, posterior margin transverse, lateral margin convex ( Fig. 30 ), posterior coxal groups (Cx-III + Cx-IV of one side) L/W 354 (318–322)/341 (294–306); genital field overall broad oval, acetabular plates broad kidney-shaped, slightly inclined to lateral, flanking 4/5 of genital opening, pre- and postgenitale laying completely under integument, genital field L/W 258 (234–252)/378 (336–342), single genital plate L/W 174 (178–188)/102 (92–94); acetabula of similar size, irregular oval, Ac-2 and Ac-3 laying beside each other, L/W Ac-1 76 (79–82)/43 (41–42), Ac-2 82 (82–85)/46 (41–48), Ac-3 89 (83–84)/40 (49–51), 18/20 (20/18, 20/22) setae of similar size on anterior, lateral and posterior margin of each plate, antero-medial of the plates 4/3 (2/3, 3/4), postero-medial 3/0 (0, 1/1) additional setae in the soft integument beside the pre- and postgenital sclerites (see Fig. 30 ); all legs slender, bearing many heavy setae, especially dorso-distally at basal segments ( Figs. 31–35 ); measurements (L/H) of distal leg segments: I-leg-5 325 (322–325)/54 (54), I-leg-6 266 (240–258)/50 (49–50); II-leg-5 342 (342–346)/54 (54– 55), II-leg-6 276 (259–270)/54 (52–54); III-leg-5 378 (372–384)/56 (58–60), III-leg-6 312 (300–312)/54 (54–55); IV-leg-3 236 (236–242)/72 (67–68), IV-leg-5 396 (396–414)/58 (54), IV-leg-6 354 (342–355)/52 (53); chelicerae strong; cheliceral claws very large, curved, distally sharply pointed, dorsal margin in the distal half with strong serration continuing proximally in a lateral serration, medially and laterally striated ( Figs. 36, 37 ); palps strong, relatively slender ( Figs. 38–40 ), ventral margin of P-2 very slightly concave (sharp bend in Fig. 38 probably misshapen), antero-ventral corner with single denticles (in some specimens none), P-3 ventrally straight to slightly convex with loose field of denticles in distal 2/3, P-4 relatively long and slender, slightly curved, with a pair of ventral setae in the distal fourth; P-5 with a blunt, cone-shaped ventro-proximal projection, dorso-distally with a compact, denticle-like distal claw, distally with a pair of large, strong, similar, ventrally-buckled claws; mouthpart measurements: Chelicera H 151 (basal part in all specimens broken), claw L 261, curvation of cheliceral claw 26°; palp total L 617 (604–616), L/H P-1 71 (61–63)/87 (85–87), P-2 161 (165–169)/99 (96–101), P-3 122 (118–122)/87 (87–92), P-4 212 (204–212)/76 (63–68), P-5 52 (52–54)/45 (54–56).

Figures

FIGURE 30. Hygrobates (Lurchibates) incognitus sp. nov., holotype female, ventral view of idiosoma; scale bar = 100 µm.

FIGURES 31–40. Hygrobates (Lurchibates) incognitus sp. nov., paratype female, Fig. 31. I-leg, left; Fig. 32. II-leg, left; Fig. 33. III-leg, left; Fig. 34. IV-leg-1-4, left; Fig. 35. IV-leg-5, -6, left; Fig. 36. right chelicera in medial view (partly broken); Fig. 37. left chelicera in lateral view (partly broken); Fig. 38. right palp in medial view; Fig. 39. left palp in medial view; Fig. 40. right palp in lateral view; scale bars = 100 µm.