Tasmaniosoma maria, 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 : 70-71

Tasmaniosoma maria sp. n.

urn:lsid:zoobank.org:act:F33C87DA-B288-4E93-8CA5-C8A744522097

Fig. 18B; map Fig. 24

Holotype. Male, Australia, Tasmania, Maria Island, Four Mile Creek , 42°37'20"S 148°04'11"E ( EN 876804) ± 250 m, 60 m, 14 August 1991, R. Mesibov, QVM 23 :46760, dissected, in genitalia vials.

Paratypes. 1 male, 4 females, Pine Hut Creek , Maria Island, Tas, 42°39'25"S 148°05'49"E ( EN 898765) ± 250 m, 20 m, 13 August 1991, R. Mesibov, QVM 23 :46759 ; 1 male, 2 females, Blind Creek , Maria Island, Tas, 42°42'24"S 148°04'42"E ( EN 882710) ± 250 m, 120 m, 15 August 1991, R. Mesibov, QVM 23 :46761 .

Other material. None known.

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 flattened lateral and medial processes with irregular apical margins on either side of a large, central laminate process.

Description. Male/female approximate measurements: length 16/ 16 mm, ring 12 paranota width 2.1/ 1.9 mm. Live colour not known; in alcohol, uniformly pale yellowish brown or decoloured.

Male 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 1.4 × 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. 18B) straight, tapering distally, somewhat constricted just above base, posteriorly thickened as ridge running distally, divided above ca 2/3 telopodite height into cluster of six processes: (a) medial, rod-like, acuminate process directed distally and slightly anteriorly; (b) medial, flattened process with expanded tip and fimbriate distal margin, directed posterodistally; (c) medial, slen- der solenomere bent posteriorly near tip; (d) large, mediolaterally flattened laminate process with curved margin, broken posteriorly by U-shaped notch, the distal border of notch slightly extended and acute; (e) anterior lateral process rod-like, directed anterolaterally, tip slightly flattened and minutely toothed; (f) posterior lateral process rod-like, acuminate, directed posterodistally. Sparse, fine setae running from base distally on lateral side of posterior ridge to ca 1/3 telopodite height; mid-lateral, longitudinal line of 3–4 fine setae; 30–40 stout, rod-like setae from ca 1/3 to 2/3 telopodite height on posteromedial surface. Prostatic groove running on medial surface more or less directly to solenomere base, curving slightly around base of medial process with fimbriate tip. (Note: Fig. 18B is a reconstruction drawn from a paratype and modified using the holotype. None of the three available males has undamaged gonopods, and the stout, rod-like setae are almost all broken off, detectable only as large setal sockets.)

Female with posterior margin of epigynum raised medially as large, rounded triangle with irregular edge.

Distribution. So far known from eucalypt forest at three localities on North and South Maria Island, with a maximum separation of ca 10 km ( Fig. 24 ). Co-occurs with T. armatum at Four Mile Creek, and T. armatum has also been collected at Ned Ryans Creek, between the two T. maria localities on North Maria Island.

Etymology. Noun in apposition; all known specimens are from Maria Island.

Remarks. The assignment of the Pine Hut Creek and Blind Creek females to T. maria is tentative. Th ey are larger than females of sympatric T. armatum but are otherwise very similar.

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).