Orthomorpha suberecta, Likhitrakarn, Natdanai, Golovatch, Sergei I. & Panha, Somsak, 2011

Likhitrakarn, Natdanai, Golovatch, Sergei I. & Panha, Somsak, 2011, Revision of the Southeast Asian millipede genus Orthomorpha Bollman, 1893, with the proposal of a new genus (Diplopoda, Polydesmida, Paradoxosomatidae), ZooKeys 131, pp. 1-161 : 38-41

Orthomorpha suberecta sp. n. Figs 3436

Holotype.

♂ (CUMZ), Thailand, Nong Bua Lamphu Prov., Suwannakhuha Distr., near Suwannakhuha Cave, 18°0'09"N, 102°28'28"E, 17.10.2007, leg. S. Panha.

Paratypes.

1 ♀ (CUMZ), same data, together with holotype.

Name.

To emphasize the suberect gonopod femorite.

Diagnosis.

Differs in a suberect gonofemorite, coupled with mostly flavous metaterga and widely separated sternal cones between ♂ coxae 4 (see also Key below).

Description.

Length ca 26 (♂) or 28 mm (♀), width of midbody pro- and metazona 2.5 and 3.9 mm (♂), 3.0 and 4.3 mm (♀), respectively.

Coloration of alcohol material after long-term preservation castaneous brown with a pattern of contrasting whitish to light brown paraterga and epiproct, and mostly greyish-white to light brownish posterior halves of postcollum metaterga, with caudal edges and front 1/4 of metaterga, as well as surface below paraterga and entire rear halves of prozona brown to dark brown; head and antennomeres 6 and 7 brown to dark brown; venter and a few basal podomeres light brownish to brown, legs growing infuscate (brown) distally (Fig. 34A-L).

Clypeolabral region sparsely setose, vertex bare, epicranial suture distinct. Antennae moderately long, clavate (antennomere 6 broadest), extending behind body segment 2 (♂, ♀) dorsally. Head in width <collum <segments 2 <3 <4 <5-17 (♂), or head <segment 3-4 <2 <5-17 (♀); thereafter body gently and gradually tapering. Collum with three transverse rows of setae: 4+4 anterior, 2+2 intermediate and 4+4 posterior; paraterga slightly declivous, broadly rounded and narrowly bordered, caudal corner a small knob not extending behind tergal margin (Fig. 34B). Tegument rather strongly shining, prozona very finely shagreened, metazona leathery, rugulose, below paraterga microgranulate and rugulose. Postcollum metaterga with an anterior transverse row of 2+2, mostly abraded setae; caudal row barely traceable as 3+3 insertion points, laterally as small knobs increasingly strongly reduced towards segment 19. Tergal setae simple, rather long, about 1/3 metatergal length, mostly abraded. Axial line visible both on pro- and metazona. Paraterga very strongly developed (Fig. 34A-G & J-L), especially well so in ♂, all lying below dorsum (at about 1/3 body height), subhorizontal, in lateral view modestly enlarged on pore-bearing segments, thinner on poreless ones; shoulders broadly rounded, and narrowly bordered, fused to callus; caudal tip of all paraterga pointed, beak-like, lying within rear tergal margin, thereafter extending increasingly beyond it, best developed and slightly curved mesad on segments 18 and 19 (Fig. 34F & G). Calluses delimited by a sulcus both dorsally and ventrally on segments 5-18. Paraterga 2 broad, anterior edge convex, lateral edge with four small acute denticles (Fig. 34A). Following poreless segments with two similar incisions, with one, often setigerous incision lying in front of pore on pore-bearing segments. Posterior edge of paraterga slightly concave, especially strongly so on se gments 18 and 19. Ozopores evident, lateral, lying in an ovoid groove at about 1/4 in front of caudal corner. Transverse sulcus visible on metaterga 5-18, narrow, not reaching bases of paraterga, ribbed at bottom. Stricture between pro- and metazona narrow and rather shallow, faintly beaded at bottom down to base of paraterga (Fig. 34B-F & K). Pleurosternal carinae complete crests with a sharp caudal tooth on segments 2-7 (♂) or 2-6 (♀), thereafter increasingly well divided into a front bulge and a caudal tooth, both increasingly strongly reduced in size until segment 17 (♂, ♀). Epiproct (Fig. 34E-G & L) conical, flattened dorsoventrally, with two evident apical papillae directed ventrocaudally, acute at tip; pre-apical papillae small denticles lying close to tip. Hypoproct (Fig. 34G) subtriangular, caudal margin rounded, setiferous knobs at caudal edge evident and well-separated.

Sterna sparsely setose, without modifications; cross-impressions shallow; a paramedian pair of evident, small, fully separated, setose cones between ♂ coxae 4 (Fig. 34I & J). A paramedian pair of small, but evident tubercles in front of gonopod aperture. Legs moderately long and slender, slightly incrassate in ♂, midbody ones ca 0.9-1.0 (♂) or 0.8-0.9 times (♀) as long as body height, prefemora without modifications, ♂ tarsal brushes absent.

Gonopods (Figs 35 & 36) simple. Coxa long and slender, with several strong setae distodorsally. Prefemur densely setose, about half the length of femorite + “postfemoral” part. Femorite suberect, slender, nearly not enlarged distad, with a “postfemoral” part demarcated by an oblique lateral sulcus. Solenophore with lamina lateralis evidently smaller than lamina medialis, tip distinctly bilobed, terminal lobule being vaguely bifid; solenomere long and flagelliform.