<Unknown Taxon>

Colless, Donald H., 2012, The Froggattimyia-Anagonia Genus Group (Diptera: Tachinidae), Records of the Australian Museum 64 (3), pp. 167-211 : 193-194

Anagonia anguliventris (Malloch)

Figs 37–39

Froggattimyia anguliventris Malloch, 1932:273. Synonymy by Crosskey (1973:138).

Type. Holotype female in USNM, Mt Stromlo, 8 Mar. 1932, Australian Capital Territory.

Male. A relatively large, dark species, generally resembling the dark form of A. rufifacies but differing as follows:

Head. Width 3.3–3.9, mean 3.60 mm; Frw/Hdw 0.2–0.2, mean 0.21; Gnw/Eyh 0.4–0.5, mean 0.42; Ivb/Vb-E 0.8–1.2, mean 0.93; the difference in width of frons and gena impart a distinctive shape to the head. Eye very sparsely or not at all haired. Reclinate upper frontal hairs strongly inclinate, the upper pairs cruciate. Soft hairs of fronto orbits not markedly long or profuse. Parafacial hairs short, strongly curved, profuse. Postocellar setae usually 2, but up to 7 sometimes present. Upper occipital hairs variable, with from very few to many dark hairs behind the postocular row.

Thorax. Presutural median dark vitta usually well developed, reaching to, or almost to suture; pollinosity of scutellum and adjacent mesoscutum usually with brownish tinge. Scutellum relatively broad at base (Sbs/Ssa 2.6–4.3, mean 3.17, the highest for the group); apical setae highly variable in shape and strength, sometimes not differentiated.

Legs. Tibiae almost always concolorous with femora, but rarely a little paler, approaching the condition in A. rufifacies (see “Notes” below). Hindtibia with pd1 bristle conspicuously long (Pd1/Sdd 0.9–1.4, mean1.15). Foretibia with preapical ad bristle extremely fine, vestigial or not at all differentiated.

Wing. Tegula dark brown, basicosta brown, usually paler at centre or margin.

Abdomen. Very dark, paler areas on tergites 3 and 4 not at all conspicuous. Tergite 3 with submedian pair of marginal bristles usually not differentiated (rarely distinct in specimens from WA).

Terminalia ( Figs 37–39 ). Remarkably small for so large a species ( Fig. 37 is drawn to the same scale as Fig. 40 ). Surstyli about as long as cerci, both rather digitate, tapering to blunt, rounded apices; epiphallus small.

Female. Relatively large, head width 3.3–3.7 mm, mean 3.6 mm; gena (as in male) relatively broad, Gnw/Eyh 0.4–0.5, mean 0.43. As usual, paler than the male, with grey-dusted scutum lacking the presutural median vitta; but with the same characteristic setation of hindtibiae and abdomen; preapical ad bristle of foretibia rather larger, but still noticeably small. Abdominal tergite 5 lozenge-shaped, remarkably produced both anteriorly and posteriorly; shape rather variable, but length usually 1.3–1.7 times breadth.

Terminalia (see Cantrell, 1988:119). Segments greatly elongated, forming a long tubular ovipositor, about 3 times as long as tergite 5; tergite 6 largely membranous, lightly sclerotized apically; tergite 7 consisting of little more than a pair of narrow, lightly sclerotized hemitergites, sternite 7 more strongly sclerotized at apex, latter rounded, rather “scoop-like”. Intersegmental membranes supported by a narrow but conspicuous, median sclerotized strip.

Distribution. Most specimens are from southern states (NSW, ACT, Victoria, SouthAustralia, and WesternAustralia). I have one aberrant specimen (see above) from North Queensland, but the species seems to be at least rare in the tropics.

Biology. In the Canberra region, the species has been reared almost entirely from Paropsis atomaria, but a few from Chrysophtharta variicollis as well; whereas the few specimens from Western Australia were reared from Paropsisterna sp. (“ amoena ”—sic) and one from Trachymela tincticollis. Identified males have also been taken frequently in light traps.

Notes. This is certainly the species described by Malloch. I have not seen the holotype but Dr Norm Woodley has checked the crucial features for me. Also in the ANIC, there are 2 males and 2 females reared from the same batch as the holotype. Moreover, A. major, which has an extremely similar female, has never appeared in extensive rearings from Paropsis atomaria, the species from which the holotype was reared.

Despite the normally dark tibiae, I have seen several males with terminalia as described above, but with the tibiae paler than the femora; two, in particular, have the foretibia conspicuously pale and the metatarsus likewise. Two females are available, presumably of this species or the next, with aberrant setation: one with a stout pair of submedian marginals on tergite 3 and distinct intrapostalars, the other with very stout intrapostalars and tergite 5 more grossly enlarged than usual. Perhaps some of these represent distinct species; but granted the wild variability of tachinids in general, I am more inclined to regard them as simple developmental or genetic variants.

The association of the sexes is based on a large series of co-reared specimens from various dates and localities around Canberra.

Figures

Fig. 37–39. Anagonia anguliventris, male terminalia, (37) lateral, and (38) posterior views, (39) aedeagus.

Figs 40–43. Anagonia major, male terminalia, (40, 41) lateral, and (42) posterior, (43) aedeagus.