Desmoxytes rhinoparva, Likhitrakarn, Natdanai, Golovatch, Sergei I. & Panha, Somsak, 2015

Likhitrakarn, Natdanai, Golovatch, Sergei I. & Panha, Somsak, 2015, Two new species of dragon millipedes, genus Desmoxytes Chamnerlin, 1923, from Laos (Diplopoda: Polydesmida: Paradoxosomatidae), with redescriptions of all four species of Attems from Vietnam, Zootaxa 3931 (4), pp. 483-504 : 489-493

Desmoxytes rhinoparva sp. n.

Figs 1 C, D, 5 & 6.

Holotype male ( CUMZ), Laos, Houaphan Province, Viengxay District, Ban Thamnathan, ca 860 m a.s.l., 20º 27' 48.1"N, 104° 08' 43.4"E, 0 5.07.2014, leg. C. Sutcharit.

Paratypes. 1 male, 1 female ( CUMZ), same locality, together with holotype. 1 male, 1 female ( CUMZ), same District, Kuar Nam Nuar, ca 840 m a.s.l., 20º 27' 11.9"N, 104° 10' 38.6"E, 0 5.07.2014, leg. R. Srisonchai.

Name. To emphasize the evident, but smaller basal spine on paraterga, much as in D. rhinoceros sp. n.; an adjective.

Diagnosis. Paraterga antler-shaped, with an evident anterior spine at base and a small tooth near tip; midbody setation pattern on metaterga a posterior row of 2+2 insertion points; gonopod rather short and condensed; male prefemora 5 humped, male prefemora 6 inflated.

Description. Length 23.1–24.2 (male) or 26.5–29.5 mm (female), width of midbody pro- and metazonae 1.4–2.0 and 4.1–4.6 mm (male) or 2.2–2.8 and 4.0– 4.6 mm (female), respectively.

Live coloration dark brown ( Fig. 1 C & D); a few basal podomeres brown to pale brown, antennae growing infuscate (black) distad; body segments 11–12 and legs contrasting pale brown to whitish; coloration of alcohol material after four months of preservation faded to brown or pale brown; venter and a few basal podomeres pale brown to whitish, legs growing infuscate (brown) distad ( Fig. 5 A–K).

Clypeolabral region densely setose, vertex sparsely setose, epicranial suture distinct. Antennae very long ( Fig. 1 C & D), either reaching body segment 6 (male) or extending behind body segment 5 (female) when stretched dorsally. In width, head <collum <segment 2 <3 <4 <5 <6–16 (both sexes); thereafter body gently and gradually tapering. Collum with two transverse rows of setigerous spines: 3+3 anterior and 1+1 posterior, anterior spines being much larger than posterior ones; paraterga antler-shaped, directed dorsolaterad, with three evident spines anteriorly ( Fig. 5 A & B). Tegument invariably dull, prozonae finely shagreened, metazonae rather coarsely microgranulate, surface below paraterga coarsely microgranulate, sterna delicately microgranulate ( Fig. 5 A–D & F–K). Metaterga with a posterior row of 2+2 setae traceable only as insertion points. Axial line not visible (both sexes). Paraterga extremely well developed, antler-shaped ( Figs 1 C, D, 5A–D, F & G), upturned, directed dorsolaterad, tip bent posteriad, with an evident anterior spine at base and a small tooth at about 3/4 extent of paraterga ( Fig. 5 A–D, F & G), paraterga 8, 9, 11, 12, 14 and 15–18 each with a small, additional, subapical spine. Ozopores (Op) lateral, located distal to notch at base of basal spine ( Fig. 5 D). Transverse sulcus usually visible in metaterga 5–17 ( Fig. 5 A, C & F), wide, line-shaped, rather deep, reaching bases of paraterga (both sexes). Stricture between pro- and metazonae wide, line-shaped, very shallow, ribbed at bottom down to base of paraterga ( Fig. 5 A–D, F & G). Pleurosternal carinae complete crests with a sharp caudal tooth only in segments 2 and 3 ( Fig. 5 B, D & G), with only an anterior crest in segment 4, absent thereafter. Epiproct conical ( Fig. 5 F, G & H), flattened dorsoventrally, apical papillae small, but evident; tip subtruncate; pre-apical papillae small setigerous knobs lying close to tip. Hypoproct subtrapeziform, evident setigerous knobs at a slightly convex caudal margin rather large and well-separated.

Sterna sparsely setose, without modifications; cross-impressions shallow; a large, rounded, sparsely setose, sternal lobe between male coxae 4 ( Fig. 5 I & J). Legs long and slender, slightly incrassate in male, midbody ones ca 1.7–1.8 (male) or 1.5–1.6 times (female) as long as body height. male сoxae 2 rather clearly elongated distoventrally ( Fig. 5 K). Male prefemora 5 with a very strong, claw-shaped, distovental, densely pilose apophysis in distal half, male prefemora 6 strongly inflated medially, with a small, but evident spine in distal half ( Fig. 5 B & E). Male tarsal brushes absent.

Gonopods ( Fig. 6 ) subfalcate, distal part directed mesally. Coxite moderately long, a little curved caudad, rather densely setose distodorsally. Prefemur densely setose, about 1/3 as long as telopodite. Femorite stout, strongly curved dorsad, slightly enlarged distad, seminal groove running entirely on mesal face. Postfemoral part rather short and condensed; solenomere short, flagelliform, sheathed by rounded solenophore (= lamina lateralis) carrying two apical lobes.

Remark. The coloration of this species is quite remarkable, being contrasting pale brownish in segments 9–11 and present in both sexes.

Figures

FIGURE 1. Habitus, live coloration. A, B: Desmoxytes rhinoceros sp. n., male holotype. C, D: Desmoxytes rhinoparva sp. n., male holotype. Photographed not to scale.

FIGURE 5. Desmoxytes rhinoparva sp. n., male holotype. A, B: anterior part of body, dorsal and lateral views, respectively. C, D: segments 9 – 11, dorsal and lateral views, respectively. E: legs 5 – 7, sublateral view. F – H: posterior part of body, dorsal, lateral and ventral views, respectively. I, J: sternal cones between coxae 4, subcaudal and sublateral views, respectively. K: coxae 2 and 3, ventral view.

FIGURE 6. Desmoxytes rhinoparva sp. n., male holotype. A, B: right gonopod, lateral and mesal views, respectively. Scale bar: 0.2 mm.