Desmoxytes aspera ( Attems, 1937 )

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 : 493-494

Desmoxytes aspera ( Attems, 1937)

Figs 7 & 8 .

Centrodesmus asper Attems, 1937: 125 (D).

Centrodesmus asper — Attems, 1938: 240 (D).

Pratinus asper — Jeekel, 1964: 62 (D, M); 1968: 61 (M).

Hylomus asper — Jeekel, 1980: 657 (M, R); Golovatch, 1983: 181 (M).

Desmoxytes aspera — Golovatch & Enghoff, 1994: 48, 60 (D, M); Enghoff et al., 2004: 37 (R); Nguyen et al., 2006: 257 (D); Nguyen & Sierwald, 2013: 1240 (R).

Lectotype male (NHMW-4243), Vietnam, Thừa Thiên-Huế Province, Bana Mountain, 1400 m a.s.l., 18.09.1931, leg. C. Dawydoff.

Paralectotype. 1 female (NHMW-4243), same locality, together with lectotype.

Lectotype designation proposed herewith is necessary to ensure the species is based on a male.

Redescription. Length ca 18 mm (male) or 22 mm (female), width of midbody pro- and metazonae 1.1 and 2.3 mm (male) or 1.8 and 3.0 mm (female), respectively (versus width of midbody pro- and metazonae 1.0 and 2.3 mm (male) or 1.65 and 3.0 mm (female), respectively, as given in the original descriptions ( Attems, 1937, 1938)).

Coloration of alcohol material upon long-term preservation red-brown ( Fig. 7 A–L); venter and legs yellowbrown, paraterga and epiproct yellow-brown to pale yellowish ( Fig. 7 A–L) (versus dark chestnut brown, tip of paraterga and posterior spines of metazonae pale yellowish; first three legs and antennae brown, as given in the original descriptions ( Attems, 1937, 1938)).

Clypeolabral region and vertex sparsely setose, epicranial suture distinct. Antennae rather long, reaching segment 4 (both sexes) when stretched dorsally. In width, head <collum <segment 2 <3 = 4 <5–17 (both sexes); thereafter body gently and gradually tapering. Collum with three transverse rows of prominent setigerous spines: 4+4 anterior, 2+2 intermediate, and 2+2 posterior; paraterga antler-shaped, directed dorsolaterad, with one evident spine each anteriorly near base and at 3/4 extent of paraterga ( Fig. 7 A & B). Tegument dull, prozonae finely shagreened, metazonae, including surface below paraterga, coarsely microgranulate, sterna delicately microgranulate ( Fig. 7 A–G & J–L). Metaterga with two transverse rows of setigerous spines, 3+3 small anterior and 3+3 thorn-shaped posterior, lateral spines of posterior rows being much longer than others; intermeditate ones shorter, mesal ones shortest, thereafter gently and gradually reduced until segment 19 ( Fig. 7 A, C, F & J–L). Axial line invisible. Paraterga antler-shaped, especially well so in male, upturned, directed dorsolaterad, tip bent posteriad, with a prominent anterior spine at 1/4 extent of paraterga and two small setigerous notches thereafter ( Figs 7 A–G, J–L). Ozopores visible (Op) from above, lying at base of first setigerous notch ( Fig. 7 C & D). Transverse sulcus complete on segments 5–17, line-shaped, rather narrow, shallow, reaching bases of paraterga; incomplete on segments 4 and 18, absent from segment 19 ( Fig. 7 A, C, F, J–L). Stricture between pro- and metazonae narrow, very shallow, ribbed at bottom down to base of paraterga ( Fig. 7 A–F, J–L). Pleurosternal carinae poorly developed, with a front bulge and a caudal tooth increasingly reduced in size until segment 4 (both sexes). Epiproct ( Fig. 7 E, F & G) conical, flattened dorsoventrally, apical papillae very small; tip subtruncate; preapical papillae small, but visible, lying close to tip. Hypoproct nearly semi-circular, setigerous knobs at a slightly convex caudal edge rather large and well-separated.

Sterna sparsely setose, without modifications; cross-impressions shallow; an elevated, subrectangular, setose lamina between male coxae 4, carrying a rounded tubercle at both corners ( Fig. 7 H & I). Legs long and slender, midbody ones ca 1.2–1.4 (male) or 0.9–1.1 times (female) as long as body height. Prefemora without modifications. male tarsal brushes absent.

Gonopods ( Fig. 8 ) suberect. Prefemur sparsely setose, as long as femorite. Femorite very stout, slightly enlarged distad, with seminal groove running entirely on mesal face. Solenophore (= lamina lateralis) welldeveloped, falcate and condensed apically, supporting a rather short flagelliform solenomere well separated at base from solenophore (versus similar to D. pilosa ( Attems, 1937) , but differing in solenophore stretched and bent, without processes, as given in the original descriptions ( Attems, 1937, 1938)).

Figures

FIGURE 7. Desmoxytes aspera (Attems, 1937), male lectotype (A – I), female paralectotype (J – L). A, B, J: anterior part of body, dorsal, lateral and dorsal views, respectively. C, D, K: segments 9 and 10, dorsal, lateral and dorsal views, respectively. E – G, L: posterior part of body, lateral, dorsal, ventral and dorsal views, respectively. H, I: sternal cones between coxae 4, subcaudal and sublateral views, respectively.

FIGURE 8. Desmoxytes aspera (Attems, 1937), male lectotype. A, B: right gonopod, lateral and mesal views, respectively. Scale bar: 0.2 mm.