Tasmaniosoma hesperium, 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 : 64-65

Tasmaniosoma hesperium sp. n.

urn:lsid:zoobank.org:act:8802E448-74E6-4BB9-8936-E31CDA3132FE

Fig. 18A; map Fig. 24

Holotype. Male, Australia, Tasmania, Mt Hesperus, Alpha Moraine , 43°06'43"S 146°14'22"E ( DN 380263) ± 100 m, 580 m, 28 February 1999, K. Bonham & R. Crookshanks, QVM 23 :46600, dissected, in genitalia vials.

Paratype. 1 male, Junction Creek, Western Arthur Plains, Tas, 43°06'21"S 146°16'35"E ( DN 410270) ± 5 km, 7 February 1966, A. Neboiss, QVM 23:46602.

Other material. None known.

Diagnosis. Gonopod telopodite apex divided into four processes, the central flattened process projecting posteriorly between solenomere and lateral process.

Description. Male with ring 12 paranota width ca 1.5 mm. Live colour unknown; in alcohol completely decoloured.

As for T. armatum in most non-gonopod details, but overall widths tergite 6>5>(4,2,head)>3>collum, antennomere 3 longest, ring 12 paranota 1.3 × as wide as prozonite, leg 6 tarsus 1.3 × as long as femur and femur longer than prefemur. Ring 2 pit circular with well-defined rim. Th ree barely detectable transverse rows of large, low tubercles on metatergites; just visible on holotype in lateral view with reflected light, not as well developed as in other Tasmaniosoma spp., e.g. T. hickmanorum sp. n. Leg 6 sternal tab short with brush of fine setae; no leg 7 tab; no setae on anterior margin of ring 6 sternite.

Gonopod telopodite (Fig. 18A) straight, slightly tapering distally, somewhat flattened mediolaterally, posteriorly with small shelf-like projection at base (concave

Figure |8. Tasmaniosoma hesperium sp. n., paratype male, QVM 23:46602 (A, B) and T. maria sp. n., paratype male ex QVM 23:46759 (C, D). A Medial and slightly ventral B posterior and slightly lateral C medial and D anterolateral views of the respective left gonopod telopodites. Setation not shown; dashed lines mark course of prostatic groove. Scale bar = 0.2 mm. Dotted lines in C and D indicate reconstructed process based on holotype.

upwards), divided at ca 3/4 telopodite height into cluster of three processes: (a) long posteromedial solenomere, curving slightly laterally; (b) central, broad, mediolaterally flattened process extending posteriorly below solenomere tip; (c) bladelike, acuminate process arising on posterolateral surface close to solenomere origin and directed distally on lateral side of central process. In addition, slender process with forked tip with origin on medial surface at ca 2/3 telopodite height, basal and slightly anterior to solenomere origin, directed anterodistally. Two tracts of sparse, fine setae: one running from basal shelf anterodistally to end laterally at ca 1/3 telopodite height, other running distally from base on posteromedial surface to ca 1/2 telopodite height. Prostatic groove running on medial surface more or less directly to solenomere base.

Female not yet recognised.

Distribution. Known only from two sites less than 5 km apart in the southwest Tasmanian wilderness, ca 40 km south-southeast of Strathgordon ( Fig. 24 ).

Etymology. Latin hesperius, “western”, adjective, referring to the names of the two known localities.

Remarks. Very similar to T. laccobium sp. n., differing mainly in gonopod details.

Figures

Figure 24. A Localities as of 31 January 2010 for Tasmaniosoma alces sp. n. (filled triangles), T. aureorivum sp. n. (crosses), T. australe sp. n. (filled squares), T.bruniense sp. n. (stars), T. hesperium sp. n. (open circles), T. laccobium sp. n. (open triangle), T. maria sp. n. (filled circles) and T. warra sp. n. (open squares). See also Fig. 23. Scale bar = 50 km. (B) Map of Tasmania showing location of main map (rectangle).