Baeus spirolimbus, Stevens

Stevens, Nicholas B. & Austin, Andrew D., 2007, Systematics, distribution and biology of the Australian ' micro-flea' wasps, Baeus spp. (Hymenoptera: Scelionidae): parasitoids of spider eggs, Zootaxa 1499, pp. 1-45 : 37-38

17. Baeus spirolimbus, Stevens , sp. nov.

( Figs 13 C & D, 17A)

Holotype, Ψ, Queensland, 'Maroochy Hort Res Stn, Nambour, S.E. QLD, 22.iii–3.iv.1985. Malaise Trap' (ANIC).

Paratypes: Queensland: 2 Ψ, Casey Ck via Imbil, 30.xii.1974 – 27.iii.1975, 16.vi–23.viii.1975, G.B. & S.R. Monteith (QDPC); 1 Ψ, Black Butt Range, Benarkin, 10.i–28.iii.1975, G.B. & S.R. Monteith (QDPC); 2 Ψ, Laceys Ck, Mission Beach, 17.54S 146.06E, 13–14.v.1980, I.D. Naumann & J.C. Cardale (ANIC); 1 Ψ, Windsor Tableland via Mt Carbine, 22.ix–16.x.1983, Storey & Titmarsh (WINC); 2 Ψ, Davies Ck Rd, 16 km up via Mareeba, 4–13.iii.1983, 18 km up, 18.i–2.ii.1985, Storey & Titmarsh (QDPC); 2 Ψ, State Forest nr Caloundra turn-off, 8.iii.1984, I.D. Galloway (QDPC); 2 Ψ, Kuranda, 6 km NW, 2.x–6.xi.1984 (QDPC); 7 Ψ, Kuranda, 6 km SW, 10.xii.1984 – 15.i.1985, Storey & Halfpapp (QDPC); 1 Ψ, same data as holotype (ANIC); 1 Ψ, 'Maroochy Hort Res Stn, Nambour, 22.iii–3.iv.1985. Malaise Trap (ANIC); 1 Ψ, Julatten, 20–29.x.1987, A. Walford-Huggins (WINC); 5 Ψ, Lake Eacham, 17.17S 145.39E, 15.ii–2.iii.1988, 2–16.iii.1988, 16– 29.iii.1988, D. Rentz (ANIC); 19 Ψ, Bald Hill, McIlwraith Ra., 13.43S 143.19E, 27.vi–12.vii.1989, I. Naumann (ANIC); 17 Ψ, Batavia Downs, 12.41S 142.41E, 23.viii–16 ix.1992, P. Zborowski & L. Miller (ANIC); 14 Ψ, Heathlands Research Reserve, 11.45S 142.35E, 25.vii–18.viii.1992, P. Zborowski & J. Cardale, 18.ix– 21.x.1992, P. Zborowski & T. Weir, 5.iv–23.v.1993, P. Zborowski & A. Roach, 23.v–18.vi.1993, P. Zborowski & I. Naumann (ANIC).

Description. Female. Mean length 0.82 mm (0.76–0.88; n = 5); body and head brown, legs and antennae yellow, both with darker markings on dorsal surfaces.

Head 2.63 (2.33–2.80) x as wide as inter-ocular distance, and 1.71 (1.52–1.83) x as wide as long; medial ocellus 15 μm in diameter, 106 (90–120) μm from posterior head margin; lateral ocelli touching eye margin, 24 (20–30) μm from posterior head margin; posterior ocellar line 1.38 (1.27–1.47) x inter-ocular distance; vertex coriarious, pilosity mostly dense, may have patches of moderate density, length generally of medium length, although some rows can exhibit short setae towards the anterior regions of the vertex; eyes large and ovoid, eye height 0.58 (0.56–0.61), eye width 0.58 (0.50–0.61) x length, pilosity short; frontal carina prominent, reaching 0.56 (0.50–0.67) distance to medial ocellus; lateral cristulations of malar region reaching to within 10 μm of eye margin; in postero-lateral view, anterior and posterior genal margins parallel medially; anterior genal margin in contact with 0.51 of ventral eye margin length; posterior eye margin touching hyperoccipital carina.

Mesosoma. Length 0.63 (0.61–0.64) x width; mesoscutum and mesoscutellum coriarious, pilosity mostly of moderate density, and of medium length but can be long in parts; propodeum glabrous medio-dorsally; mesoscutum length 0.43 (0.42–0.44) x width, 0.63 (0.61–0.65) x mesosoma length and 2.44 (2.20–2.80) x mesoscutellum length; mesoscutellum 2.33 (1.67–2.50) x as long as propodeum; sculpturing of dorsal mesopleuron scrobiculate, sculpturing extending ventral to level of dorsal metapleuron; sculpturing of laterodorsal propodeum around spiracle mostly smooth with few fine setae present; propodeal spiracle opening small and ovoid, situated on lateral margin of dorsal propodeum ( Fig. 13 C), which is delineated from lateral propodeum by distinct, laterally projecting carina ( Fig. 13 D; large arrow); distinctive quarter-circle shaped recess present below lateral carina ( Fig. 13 D; small arrow); posterior margin of metapleuron curving dorsally, ending ventral to level of antero-lateral margin of T2, posterior region level with anterior region of lateral propodeum, depression present in medial region of posterior metapleuron and anterior propodeum; hind femoral spine reduced.

Metasoma. T2 length 0.87 (0.83–0.89), sculpturing coriarious; pilosity generally of moderate density medio-anteriorly, but sparse elsewhere, and mostly long in length, but can be of medium length in parts; both T3 and T4 smooth, non-pilose medially.

Comments. Notable features of this species are the propodeal spiracle being situated close to the lateral margin of the laterally projecting carina, and the distinctive quarter-circle shape of the recess below this lateral carina. It is confined to north eastern Australia ( Fig 17 A). The name ' spirolimbus' is from the Latin words that relate to the closeness of the propodeal spiracle to the lateral margin of the lateral carina; spiro, meaning breathe, and limbus, meaning fringe.

Figures

FIGURE 13. Female Baeus spp.: A & B, B. scrobiculus: A, lateral habitus; B, latero-anterior head and mesosoma, latero-dorsal margin of propodeum (arrow) rounded. C & D, B. spirolimbus: C, dorsal habitus, propodeal spiracle (arrowed) on the lateral margin; D, latero-anterior head and mesosoma, fc = frontal carina; laterally projecting carina on latero-dorsal margin of propodeum (long arrow) clearly delineates the lateral part of the propodeum from the dorsal part, distinctive quarter-circle shaped recess present below lateral ridge (short arrow); cristulations of malar region (distorted arrow). Scale lines, A – C = 200 μm; D = 100 μm.

FIGURE 17. Distribution maps: A B. spirolimbus, B. tropaeumusbrevis; B B. tropaeumusdensus, B. vulcanus.