Gasterogramma austrinum, Mesibov, 2003

Mesibov, Robert, 2003, The millipede genus Gasterogramma (Diplopoda: Polydesmida: Dalodesmidae) in Tasmania, Australia, with descriptions of seven new species, Memoirs of Museum Victoria 60 (2), pp. 207-219 : 211

Gasterogramma austrinum sp. nov.

Figures 1 , 5 , 12 (map)

Material examined. Holotype. Male. Australia, Tasmania. Huon R. (Arve Rd), DN784273 [43º06´23´´ 146º44´04´´], 120 m, 2 May 1997, R. Mesibov, plot 3M1, oldgrowth wet eucalypt forest with rainforest understorey, QVM 23 :40628.

Paratypes. 3 males, Huon R. ( Edwards Rd ), DN790284 [43º05´48´´ 146º44´31´´], 90 m, 23 May 1997, R. Mesibov, plot 3R6, regrowth wet eucalypt forest following clearfelling and burning, QVM 23 :40630; 2 males, Edgar Bay area , DN483404 [42º59´13´´ 146º21´57´´], 350 m, pitfall emptied 16 Nov 2001, D. Driscoll, QVM 23 :24802; 4 males, Huon R. ( Arve Rd ), DN798284 [43º05´48´´ 146º45´06´´], 200 m, 16 May 1997, R. Mesibov, regrowth wet eucalypt forest following clearfelling and burning, AM KS85097 (formerly QVM 23 :40629) .

Other material. 19 males from 8 unique localities in southern Tasmania, including Gold Creek, Huon R., Kallista Creek, Picton R., Reuben Falls and Tahune Bridge .

Diagnosis. Gonopod with no femoral process or tibiotarsus; telopodite in posterior view ending in broad, mesodistally directed point.

Description. Males c. 17–20 mm long and c. 1.8–2.0 mm wide at midbody. Body in both sexes darkly mottled with pink-purple pigmentation. Gonopod telopodites slender in posterior view, lightly joined for about half their length, a few short, coarse setae at their bases, setate area extending just outside aperture (fig. 1). Aperture more or less ovoid, long axis transverse, posterior margin not noticeably raised. Telopodite with a posteromesal concavity near base, somewhat sinuous in lateral view, curving anteriorly, then distally, then anteriorly and slightly tapering, finally tapering mesally to end in blunt, mesodistally pointed tip. Femoral process and tibiotarsus not evident. Solenomerite short, helical, tapering process arising at about four-fifths length of telopodite on its posterior face. Prostatic groove running distally and posteriorly along mesal side of telopodite, then curving laterally before running straight distally to enter solenomerite on its mesal side.

Distribution. In rainforest and wet eucalypt forest over at least 750 km 2 in southern Tasmania (fig. 12), at altitudes c. 50– 600 m.

Etymology. From Latin austrinus, southern, adjective. This species is restricted to southern Tasmania.

Figures

Figure 1. (left) G. austrinum sp. nov., Tahune Bridge, southern Tasmania, QVM 23:16195; SEM of gonopods in situ. Scale-bar = 0.5 mm. (right) G. austrinum sp. nov., Gold Creek, southern Tasmania, QVM 23:14021; outline sketches of right gonopod showing course of prostatic groove (dashed line): lateral view, left; posterior view, right.

Figure 5. Sketches of epiproct form. A, Typical form in Gasterogramma; G. austrinum paratype, QVM 23:40629; lateral view. B, G. plomleyi, male paratype, QVM 23:8068, lateral view. C, same specimen as B, ventral view.

Figure 12. Localities for males of G. austrinum sp. nov. (n south), G. extremum sp. nov. (+, far south), G. imber sp. nov. (s, west and southwest), G. rusticum sp. nov. (nn, north-central), G. tarkinense sp. nov. (*, north-west) and G. wynyardense sp. nov. (•, north-west), and for all specimens of G. plomleyi sp. nov. (half-filled squares, north-east).