Tasmaniosoma barbatulum, Mesibov, 2010

Mesibov, Robert, 2010, The millipede genus Tasmaniosoma Verhoeff, 1936 (Diplopoda, Polydesmida, Dalodesmidae) from Tasmania, Australia, with descriptions of 18 new species, ZooKeys 41 (4), pp. 31-80 : 46-48

Tasmaniosoma barbatulum sp. n.

urn:lsid:zoobank.org:act:8B93AB56-F248-4A5C-99C9-EBAC6901ED28

Figs 3B , 5B , 10A; map Fig. 25

Holotype. Male, Australia, Tasmania, Scamander , 41°26'45"S 148°14'51"E ( FQ 041108) ± 100 m, 80 m, pitfall emptied January 2001, R. Bashford, QVM 23 :51554.

Paratypes. 1male, Th ompsons Marshes, Tas, 41°41'54"S 148°13'21"E ( FP 016828 ) ± 250 m, 490 m, 9 June 1988, R. Mesibov, QVM 23 :51521 ; 1 male, S of Dogwood Hill , Tas, 41°41'07"S 148°10'48"E ( EP 981843) ± 250 m, 580 m, 14 July 1988, R. Mesibov, QVM 23 :51522 ; 2 males, details as for holotype, QVM 23 :51512 .

Other material. None known.

Diagnosis. Metatergites with three transverse rows of large, low, contiguous tubercles; leg 7 sternal tab with dense brush of stout, rod-like setae; gonopod telopodite with two combs of long, stout, rod-like setae, the posterior comb directed basally, the anterior comb distally.

Description. Male ca 10 mm long, ring 12 paranota width ca 1.0 mm. Live colour not known; in alcohol completely decoloured.

Most non-gonopod details as for T. armatum , but antennal sockets separated by ca 2.5 × socket diameter, relative widths tergite 6>(5,head)>4>(3,2)>collum, ring 12 paranota ca 1.2 × as wide as prozonite, brush setae lacking on femur, gonopod aperture rim not produced. Metatergite ( Fig. 3B ) almost completely covered with three transverse rows of ca 12 large, low tubercles, each with small seta near posterior edge. Ring 2 pit not apparent except as slight concavity near anterior margin of ring. Ring 6 sternite

Figure |0. Posterior views of gonopod telopodites in situ of topotypical male paratypes, with solenomere (s) indicated. A Tasmaniosoma barbatulum sp. n., ex QVM 23:51512 B Tasmaniosoma clarksonorum sp. n., ex QVM 23:46583. Scale bars: (A) = 0.1 mm, (B) = 0.2 mm. Slight bending of flattened apical process in (A) is a preparation artifact; tip of central branch of central process on right telopodite in (B) is broken off. Portions of the background in (A) have been digitally edited for clarity.

( Fig. 5B ) with short leg 6 tab bearing a few fine setae; leg 7 tab long, thickened, with brush of stout setae; a few fine setae on anterior margin of sternite.

Gonopod telopodite (Fig. 10A) subcylindrical with small posterior extension at base, concave distally. Apex slightly produced posteriorly as rounded, thickened ridge, oriented obliquely to telopodite longitudinal axis (medial end of ridge lowest); basal surface of ridge with comb of 15–20 stout, pointed, rod-like setae, up to ca 1/4 telopodite height in length, directed basally. Solenomere short. cylindrical, acute, arising from medial end of ridge on distal side, directed distally. Telopodite apex with laminate process arising anteromedially; outer edge of process extended distally as long, rounded-truncate tab and medially as short, round-tipped tab, and bearing a small, flattened process arising mid-laterally near laminate process base and directed posterodistally. Anterior surface of telopodite with comb of 5–10 stout, pointed, rod-like setae, directed distally and arising in near-longitudinal row, increasing in length distally. A few fine setae posterolaterally near telopodite base and on concave surface of basal extension; ca 6 fine setae in midlength lateral row. Prostatic groove running distally on medial surface of telopodite directly to solenomere base.

Female not yet recognised.

Distribution. Known from dry and wet eucalypt forest at three sites on the northern part of the east coast of Tasmania, from Scamander to ca 10 km south of St Marys, a distance of ca 30 km ( Fig. 25 ). Sympatric with T. orientale sp. n.

Etymology. Latin barbatulus, “with a small beard”, adjective, for the basally directed comb of rod-like processes on the gonopod telopodite.

Figures

Figure 3. A, B Dorsal views of ring 12 metatergite of A Tasmaniosoma warra sp. n., paratype male QVM 23:46038, showing smooth surface, and B T. barbatulum sp. n., paratype male ex QVM 23:51512, showing three transverse rows of large, low, contiguous tubercles. C, D Ventral views of legpair 2 of C T. armatum Verhoeff, 1936, topotypical female ex QVM 23:46567, and D T. australe sp. n., paratype female ex QVM 23:46575, showing prefemoral swelling (s) and peg-like projection (p). Scale bars = 0.5 mm.

Figure 5. Male ring 6, ventral view (anterior to top) showing variation in structure. A Tasmaniosoma armatum Verhoeff, 1936; no leg 6 tab; short, thin leg 7 tab with brush of fine setae; paired and raised brushes of fine setae medially on anterior margin of sternite B T. barbatulum sp. n.; short leg 6 tab with a few fine setae; long, thickened leg 7 tab with brush of stout setae; a few scattered setae on anterior margin C T. fasciculum sp. n.; short leg 6 tab with a few fine setae; long, thickened leg 7 tab with brush of stout setae; no setae on anterior margin D T. hickmanorum sp. n.; no leg 6 tab; long, thickened leg 7 tab with brush of stout setae; anterior margin with wide median notch. Scale bars = 0.2 mm.

Figure 25. A Localities as of 31 January 2010 for Tasmaniosoma barbatulum sp. n. (squares), T. clarksonorum sp. n. (crosses), T. decussatum sp. n. (open circles) and T. fragile sp. n. (triangles). See also Figs 23 and 26. Scale bar = 50 km. B Map of Tasmania showing location of main map (rectangle).