Baeus vulcanus, 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 : 43

20. Baeus vulcanus, Stevens , sp. nov.

( Figs 14 E & F, 17B)

Holotype, Ψ, Queensland, 'Samford, Q., 18 Sept.1968, G. Monteith'; 'ANIC Berlesate No. 115, Dry Sclerophyll' (ANIC).

Paratypes: Queensland: 4 Ψ, Black Butt Ridge, Benarkin, G.B. & S.R. Monteith (QDPC); 1 Ψ, Cooloola, 25.xii.1974 – 27.iii.1975, G.B. & S.R. Monteith (QDPC); 2?, Mt Tamborine, xi.1978 –i.1979, 6–17.iii.1981, Agard (QDPC); 5 Ψ, Mt Glorious, 10–31.i.1982, ii.1982, 14.xi.1986 – 30.i.1987, T. Hiller (ANIC, QDPC); 1 Ψ, Maroochy Horticultural Research Stn, Nambour, 22–29.iii.1985 (QDPC); New South Wales: 1 Ψ, Tooloom Plateau, via Urbenville, 11.xi–24.xii.1973 (QDPC); 2 Ψ, New Brighton Beach, 25.xii.1974 – 21.iii.1975, G.B. & S.R. Monteith (ANIC); 1 Ψ, O'Sullivans Gap Res., 11 km NE Buladelah, 11.vi–27.viii.1982, S. & J. Peck (ANIC); 1 Ψ, Mt Wog Wog, 4 km NE of, 37.04S 149.28E, ii.1987, C.R. Margules (ANIC).

Description. Female. Mean length 0.80 mm (0.77–0.85; n = 5); body and head brown, legs and antennae lighter, both with darker markings dorsally.

Head. 2.16 (2.12–2.24) x as wide as inter-ocular distance and 1.67 (1.57–1.73) x as wide as long; medial ocellus 20 μm in diameter, 80 μm from posterior head margin; lateral ocelli touching eye margin, and are 20 μm from posterior head margin; posterior ocellar line 1.19 (1.18–1.24) x inter-ocular distance; vertex coriarious, pilosity generally sparse in density, but patches of moderate density can occur, and mostly short in length, but can be of medium length in patches; eyes large and ovoid, eye height 0.57 (0.56–0.58) x head height, eye width 0.56 (0.53–0.58) x length, pilosity short; frontal carina broad, prominent, but short, reaching 0.40 (0.30–0.46) 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 0.57 (0.56–0.59) of ventral eye margin length; posterior eye margin touching hyperoccipital carina.

Mesosoma. Length 0.56 (0.52–0.64) x width; mesoscutum and mesoscutellum faintly coriarious, pilosity mostly of moderate density along anterior regions of both sclerites but gradates to sparse posteriorly, mostly of medium length but can be short in patches; propodeum plicate medio-dorsally; mesoscutum length 0.43 (0.42–0.44) x width, 0.66 (0.61–0.69) x mesosoma length and 3.17 (2.75–3.67) x mesoscutellum length; mesoscutellum length 1.67 x propodeum length; dorso-lateral propodeum dominated by large, round propodeal spiracle (opening? 20 μm diameter), margins form large, distinct cone resembling a volcano; posterior margin of metapleuron mostly straight, curving marginally dorsally, reaching dorsal to level of antero-lateral margin of T2, posterior margin not elevated above anterior margin of lateral propodeum; hind femoral spine large (? 20 μm in length).

Metasoma. T2 length 0.92 (0.91–0.94) x width, sculpturing coriarious; pilosity mostly sparse and short, glabrous band along posterior margin short; both T3 and T4 smooth and bearing one row of setae posteriorly.

Comments. Baeus vulcanus is easily distinguished from all other Baeus spp. by its large prominent propodeal spiracles and large hind femoral spines. The namesake of this species relates to the propodeal spiracle resembling a volcano, and is therefore named after Vulcan, the Roman god of fire, who established his forge within the volcanicly active Mount Etna. Baeus vulcanus is found along the eastern seaboard from northern Queensland to northern New South Wales ( Fig. 16 B).

Acknowledgments

We wish to thank Lubomir Masner, Norm Johnson and John Jennings for their help and advice with this project, the curators of the various collections listed above for loan of material, and the staff at Adelaide Microscopy (The University of Adelaide) for assistance with the SEM. This project was funded in part by grants from the Australian Biological Resources Study, the Australian Research Council, and The University of Adelaide. ADA would also like to acknowledge support from the NSF-PBI program.

Figures

FIGURE 14. Female Baeus spp.: A & B, B. tropaeumusbrevis: A, lateral habitus; B, latero-dorsal habitus. C & D, B. tropaeumusdensus: C, lateral habitus; D, dorsal habitus. E & F, B. vulcanus: E, lateral habitus; F, dorsal mesosoma. Scale lines, A, C, & D = 200 μm; B, E, & F = 100 μm.

FIGURE 16. Distribution maps: A B. matthewi, B. moorei; B B. murphyi, B. mymyae; C B. ocellatus, B. prolatusspissus; D B. saliens, B. scrobiculus.