Baeus tropaeumusdensus, Stevens, 2007

Stevens, N. B. & Austin, A. 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 : 41-42

19. Baeus tropaeumusdensus, Stevens , sp. nov.

(Figs 7F, 14C & D, 17B)

Holotype, [[female]], Tasmania, ' Eugenana , TAS, 8.Apr.1988, L. Hill, Euc. viminallis forest' ( ANIC).

Paratypes: Queensland: 1 [[female]], Mareeba , 22km WSW of, 7.i-12.ii.1985, Storey & Halfpapp ( QDPC) ; New South Wales: 1 [[female]], Bundanoon , 2 km SSE of, 3.iv.1982, L. Hill ( ANIC) ; Australian Capital Territory: 3 [[females]], Wombat Ck, 6 km NE of Piccadilly Circus , 35.19S 148.51E, 15.xi.1984, i.1985, Lawrence, Weir & Johnson ( ANIC) ; Western Australia: 1 [[female]], Stirling Range N.P. , 11-15.i.1987, J.S. Noyes ( BMNH) .

Description. Female. Mean length 0.73 mm (0.71-0.75; n = 5); body and head dark brown, almost black, legs and antennae brown.

Head. 1.78 (1.75-1.81) x as wide as inter-ocular distance and 1.72 (1.65-1.76) x as wide as long; medial ocellus 10 µm in diameter, 68 (60-70) µm from posterior head margin; lateral ocelli not touching eye margin but within 10 µm, and are 20 µm from posterior head margin; posterior ocellar line = inter-ocular distance; vertex coriarious along anterior region to imbricate posteriorly, pilosity dense and medium in length throughout; eyes circular, height 0.47 (0.44-0.48) x head height, eye width 0.50 (0.46-0.54) x length, pilosity of medium length; frontal carina broad, and prominent, reaching 0.50 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 0.72 (0.67-0.75) of ventral eye margin length; posterior eye margin not touching hyperoccipital carina, is 20 µm from posterior head margin.

Mesosoma. Length 0.66 (0.64-0.68) x width; mesoscutum and mesoscutellum imbricate, pilosity dense and medium in length throughout; posterior margin of mesoscutellum broadly extending over dorsal propodeum to beyond anterior margin of T2; mesoscutum length 0.49 (0.45-0.52) x width, 0.65 (0.63-0.69) x mesosoma length and 1.87 (1.67-2.20) x mesoscutellum length; sculpturing of dorso-lateral mesopleuron and propodeum anterior to spiracle confused, region of latero-dorsal propodeum, posterior of spiracle, bearing short carinae, each with a long bristle posteriorly, and a longer, more distinct carina ventral to spiracle that is not prominent enough to delineate lateral propodeum from dorsal propodeum; propodeal spiracle opening small and ovoid; posterior margin of metapleuron distinct, straight, and short, ending dorsal to level of anterolateral margin of T2, posterior region of metapleuron level with anterior region of lateral propodeum; hind femoral spine absent.

Metasoma. T2 length 0.97 (0.86-1.11) x width, imbricate anteriorly to coriarious posteriorly; pilosity dense, and medium in length throughout, glabrous band along posterior margin short; T3, transverse coriarious band present medially, bearing two rows of setae; T4 similar, but only one row of setae present.

Comments. As the names suggests, B. tropaeumusdensus is similar to B. tropaeumusbrevis in that the mesoscutellum extends over the propodeum reaching the anterior margin of T2.

Therefore, the first part of the name is similarly derived (see Comments above) and the second part, densus, means dense and thick in Latin, which relates to the species’ pilosity.

Although not commonly collected, B. tropaeumusdensus has a widespread distribution (Fig. 17B).