Lissodesmus grampianensis, Mesibov, 2008

Mesibov, Robert, 2008, The millipede genera Gephyrodesmus Jeekel, 1983 and Orthorhachis Jeekel, 1985 in southeastern Australia, a new Lissodesmus Chamberlin, 1920 from Victoria, and observations on male leg setae, spinnerets and metatergite sculpture (Diplopoda: Polydesmida: Dalodesmidae), Zootaxa 1790, pp. 1-52 : 49-50

Lissodesmus grampianensis n. sp.

Fig. 33; map Fig.12

Holotype: Male. Stoney Creek , Grampians National Park, Vic, 37º08'56"S 142º28'30"E, 650 m, 12 November 2005, R. Mesibov, T. Moule & R. van Riet. In MV, K-10647.

Paratypes: In MV: 1 stadium 7 male, Dairy Creek , Grampians National Park, Vic, 37º11'01"S 142º30'30"E, 490 m, 4 October 2005, R. Mesibov & T. Moule, K-10642 ; 1 male, 1 female, location as for holotype but 4 October 2005, R. Mesibov & T. Moule, K-10643, 10644 ; 2 females, ' Wonderland' , Grampians National Park, Vic, 37º08'44"S 142º30'09"E, 390 m, 6 October 2005, R. Mesibov & T. Moule, K-10645, 10646 ; 1 male, 2 stadium 7 males, 4 females, details as for holotype, K-10648–10654.

In AM: 1 male , Mt William , Grampians National Park, Vic, 37º15'36"S 142º34'06"E, 630 m, 13 November 2005, R . Mesibov , T . Moule & R . van Riet ; KS 103043 .

Other material examined: None available.

Diagnosis: Lissodesmus sensu Mesibov (2006) with the femoral process of the gonopod telopodite very long and thin, the tip curving medially and lying just under the slightly flexed tip of the prefemoral process.

Description: Male/female approximate measurements: length 19/ 20 mm, midbody vertical diameter 1.5/ 1.5 mm, midbody width across paranota 2.0/2.0 mm. In alcohol, well-coloured specimens pale with sparse reddish mottling dorsally, denser mottling on paranota, on posterior edge of metatergites and along anterior edge of collum, with quadrangular red mark anteriorly and medially on vertex.

Male with antennal sockets moderately impressed ventrolaterally, separated by about 1.5 X a socket diameter. Antenna short, barely reaching ring 3 when manipulated to extend backwards; relative length of antennomeres 2>(3,6)>(4,5), antennomere 6 widest. Collum slightly wider than head, narrower than tergite 2; sparsely setose anteriorly; anterior edge nearly straight in the middle, slightly convex laterally; posterior edge nearly straight, corners rounded. Rings 2–18 nearly equal in overall width. Waist well-defined, with faint longitudinal striations. Prozonites and metazonites smooth, transverse furrow only faintly indicated; limbus composed of long, narrow, flat tabs with irregularly toothed ends. Paranota smooth, swollen, wide (ratio of ring 12 overall width to prozonite width = 1.5); anterior shoulder broadly curved; lateral margin slightly thickened, slightly convex, slightly upturned, with 5–6 small notches each usually with one very short seta on anterior corner of notch; margin nearly straight in lateral view; posterior corner produced into broad tooth beginning ca. ring 9, teeth increasing in length from ring 9 to 19; posterior corner seta prominent. Ozopore small, opening dorsally and laterally close to paranotal margin and just anterior to base of posterior corner; pore formula 5, 7, 9, 10, 12, 13, 15–19. Spiracle nearly round, very slightly raised above pleural surface; anterior spiracle on diplosegments larger, posterior spiracle about midway between leg bases. Sternites very sparsely setose, slightly longer than wide; transverse impression deeper than longitudinal. Legs short, prefemur greatly swollen dorsally, femur somewhat swollen dorsally, both more so on anterior legs; most legs with postfemur and tibia expanded ventrodistally; relative podomere lengths tarsus>(prefemur, femur)>(postfemur, tibia) on anterior legs, femur>prefemur posteriorly; tarsus straight. On anterior legs, sphaerotrichomes on prefemur, femur, postfemur, tibia and tarsus, hemispherical with sharp-pointed, tapered setal shaft inclined distally and slightly outwards; brush setae on prefemur and femur, tapering with sharp-pointed tips. Pre-anal ring moderately setose; hypoproct trapezoidal; epiproct bluntly rounded, extending well past anal valves; 4 spinnerets in square array, all 4 within a shallow, low-walled cavity just below epiproct tip.

Gonopore small, opening on rounded, mediodistal enlargement of leg 2 coxa. Gonopods extending to leg 4 bases when retracted; bases of legs 5, 6 and 7 well-separated, 4 less so. Aperture ovoid, wider than long, about two-thirds the width of the ring 7 prozonite, rim raised laterally. Gonocoxae small, bean-shaped, lightly joined posteromedially, with a few long setae on posterolateral surface. Telopodite ( Fig. 33) long, straight, slender, setose on posterolateral surface to level of solenomere base. Using nomenclature as in Mesibov (2006 a): telopodite base nearly cylindrical; tibiotarsus arising at just under half the telopodite length on medial side, a little flattened anteroposteriorly, directed posteriorly at ca. 45º to long axis of telopodite and slightly medially, lateral edge serrate; solenomere arising just anterior and distal to tibiotarsus, a little flattened mediolaterally, bent posteriorly and medially parallel to tibiotarsus, with small backward-pointing process near tip on anterior edge; prefemoral process tapering at ca. two-thirds the telopodite length, curving medially, then laterally, bending slightly posteriorly, flattening and expanding near tip, the tip slightly flexed and twisted medially so lateral edge faces caudad, lateral edge produced into a comb of ca. 15 teeth; a small, notched uncus on posterior surface of prefemoral process at ca. one-third the length of process; femoral process arising on lateral side of telopodite just distal to solenomere base, process long, thin, subcylindrical, tapering very gradually, curving medially and posteriorly so tip lies just basal to tip of prefemoral process, two prominent, blunt teeth on anterior surface near tip, tip blunt. Cannula prominent; prostatic groove curving laterally, then medially on anterior surface of telopodite before joining base of solenomere, opening at solenomere tip.

Female closely resembling male but very slightly larger, legs not swollen. Genital aperture with posterior margin slightly raised, centre further raised, rounded; cyphopods not examined.

Distribution: So far known only from wet sclerophyll forest at four sites from 390–650 m on the eastern edge of Grampians National Park between Halls Gap and Mt William, a total area of ca. 50 km 2 ( Fig. 12). In and under rotting logs.

Etymology: For the Grampians, an isolated set of picturesque mountain ranges in western Victoria, home to this species.

Remarks: L. grampianensis is substantially different in gonopod form from its nearest congener, L. catrionae , which occurs ca. 60 km to the east on Mt Cole, and both species differ significantly from the co-occurring L. blackwoodensis and L. macedonensis , ca. 80 km further east. The two former species appear to be 'mountain island' endemics, restricted to cloud-stripping forest on higher ground in a landscape which is otherwise largely flat and non-forested. Geographically restricted, forest-dwelling Lissodesmus species may be found in future on other isolated mountains in western Victoria.