Tasmaniosoma laccobium, 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 : 68-69

Tasmaniosoma laccobium sp. n.

urn:lsid:zoobank.org:act:12CBDFC1-DC15-400E-9CD6-D03C6A75D359

Fig. 20 ; map Fig. 24

Holotype. Male, Australia, Tasmania, Lake Sydney , 43°17'15"S 146°36'52"E ( DN 686070) ± 100 m, 690 m, 2 February 1994, R. Mesibov, QVM 23 :46601, dissected, in genitalia vials.

Paratypes. 1 stadium VI male, 1 stadium VI female, details as for holotype, QVM 23:51542.

Other material. None known.

Diagnosis. Gonopod telopodite apex divided into four processes, the central flattened process projecting posterobasally below (basal to) solenomere and lateral process.

Description. Male with ring 12 paranota width ca 1.4 mm. Live colour not known; in alcohol decoloured.

As for T. armatum in most non-gonopod details, but overall widths tergite 6>5>4>(3,2,head)>collum, antennomere 3 longest, ring 12 paranota 1.25 × as wide as prozonite, leg 6 tarsus 1.4 × 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. 20 ) slender, tapering slightly distally, curved posteriorly, slightly constricted near base, with short, shelf-like basal extension posteriorly. Divided at ca 3/4 telopodite height into tight cluster of four processes: (a) slender, rod-like, slightly sinuous, medial solenomere directed posterodistally; (b) blade-like, mediolaterally flattened, apically acute process arising just anterior and basal to solenomere and curving posteriorly; (c) mediolaterally flattened central process directed posteriorly, the basal portion of the broad apex extending posterobasally as finger-like extension; (d) broad, anteroposteriorly flattened lateral process, the medial corner of wide, truncate apex extending just posterior to solenomere. Two groups of sparse, fine setae: posterobasal group reaching to ca 1/4 telopodite height, and longitudinal medial tract extending from ca 1/4 to ca 2/3 telopodite height. Prostatic groove running on medial surface more or less directly to solenomere base.

Female not yet recognised.

Distribution. So far known only from cool temperate rainforest at the type locality in the mountains of far southern Tasmania ( Fig. 24 ).

Etymology. Greek lakkos, “pond”, + bios, “life”, noun used as adjective, after the type locality, Lake Sydney.

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

Figures

Figure 20. Tasmaniosoma laccobium sp. n., male holotype, QVM 23:46601. A medial, B posterior and C lateral and slightly posterior views of left gonopod telopodite. Setation not shown in A and C dashed line marks course of prostatic groove. Scale bar = 0.2 mm.

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).