Tasmaniosoma orientale, 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: 71-72

publication ID

http://doi.org/ 10.3897/zookeys.41.420

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scientific name

Tasmaniosoma orientale

sp. n.

Tasmaniosoma orientale   sp. n.


Fig. 21; map Fig. 26 View Figure 26

Holotype. Male, Australia, Tasmania, Elephant Pass , 41°38'26"S 148°14'32"E ( FP 034892 View Materials ) ± 25 m, 340 m, 20 August 2009, R. Mesibov, QVM 23 View Materials :51551. GoogleMaps  

Paratypes. 1 male, Tinmine Creek , Tas, 41°41'55"S 148°11'41"E ( EP 993828 View Materials ) ± 250 m, 530 m, 11 June 1988, R. Mesibov, QVM 23 View Materials :45991 GoogleMaps   ; 1 male, same details but 41°42'08"S 148°12'38"E ( FP 006824 View Materials ) ± 250 m, 450 m, 22 June 1988, QVM 23 View Materials :46000 GoogleMaps   ; 1 female, same details, QVM 23 View Materials :46001   ; 1 female, same details but 41°41'33"S 148°10'36"E ( EP 978835 View Materials ) ± 250 m, 550 m, 29 June 1988, QVM 23 View Materials :46008 GoogleMaps   ; 1 male, same details but 41°41'59"S 148°11'15"E ( EP 987827 View Materials ) ± 250 m, 500 m, 30 June 1988, QVM 23 View Materials :51550 GoogleMaps   .

Other material examined. 37 males and 38 females from 43 other sites (see Appendix).

Diagnosis. Metatergites without tubercles; ring 6 sternite with discrete setal brushes on anterior margin; gonopod telopodite with stout, rod-like setae in longitudinal tract on posteromedial surface and solenomere divided into apically bifid distal branch and distally curved, acuminate basal branch.

Description. Male/female approximate measurements: length 16/ 16 mm, ring 12 paranota width 1.8/ 1.8 mm. Male as for T. armatum   in live colour and most non-gonopod details, but long-preserved specimens completely decoloured, overall widths tergite 6>5>4>3>(2,head)>collum, ring 12 paranota 1.4 × as wide as prozonite. Ring 6 sternite as for T. armatum   , but with very short, thin sternal tab by leg 6, not bearing setae.

Gonopod telopodite (Fig. 21) similar to that of T. armatum   (see Fig. 7A View Figure 7 ), but process 1 simply acute (but see Remarks) rather than Y-shaped; process 2 undivided, curving medially, apically expanded and flattened with dentate margin; distal margin of laminate process not extended posteriorly, instead curving smoothly to posterior extension, the latter shorter and straighter than in T. armatum   ; solenomere divided into distal branch with bifid tip carrying prostatic groove, and basal branch directed posteriorly but curving distally, with pointed tip; process 3 an anteroposteriorly flattened, quadrate tab, the margin free distally apart from central attachment; process 4 as in T. armatum   ; laterally with group of 5–6 setae, rather than three.

Female with posterior margin of epigynum raised in centre as irregularly edged triangle.

Figure 2 View Figure 2 |. Tasmaniosoma orientale   sp. n. A Posterolateral view of gonopods in situ, voucher male ex QVM 23:46018 B medial and C posterolateral views of left gonopod telopodite of paratype male ex QVM 23:51550. Setation not shown in A and C; dashed line marks course of prostatic groove. Processes labelled as in Fig. 7A View Figure 7 . Scale bars = 0.2 mm.

Distribution. Common and sometimes locally abundant in dry and wet eucalypt forest over ca 1500 km 2 in the northern part of the east coast and Eastern Tiers of Tasmania, from near sea level to at least 1000 m elevation ( Fig. 26 View Figure 26 ). Not yet found north of Beaumaris or south of Bicheno on the coast, or west of St Pauls Dome in the Fingal Valley. Sympatric with T. barbatulum   sp. n. and T. fragile   sp. n.; co-occurs with the latter. T. orientale   may be parapatric with T. armatum   in the west and south of its range, and with T. cacofonix   sp. n. in the north; further sampling is needed to better define the range boundaries of these three species.

Etymology. Latin orientalis, “eastern”, for the eastern Tasmanian distribution of this species.

Remarks. The lateral process on the gonopod telopodite (process 1) is simply acute in the holotype and the specimen illustrated in Figs 21B and 21C. In some East Coast males the process is apically forked, as in the right telopodite in Fig. 21A. In the west of the T. orientale   range, the lateral process is wider and Y-shaped, as in T. armatum   .

Female T. orientale   are readily distinguished from those of sympatric, similarly sized T. fragile   sp. n. by the presence of large tubercles on T. fragile   tergites.


Departamento de Geologia, Universidad de Chile