42 R. W. CROSSKEY 
absent (present at least in some species of Chetogaster); scutellum typically with three pairs 
of strong marginal setae (Text-fig. 70) (including crossed or convergent apicals) but most 
Rutiliini with more pairs of marginals (4-11) and apicals often reduced; mid tibia with a v 
submedian seta; hind tibia with or without pv apical seta; suprasquamal ridge often haired 
(Rutiliini); abdominal Tz + 2 usually excavate to its hind margin (not in Doleschallini); 
abdominal sternites concealed by ventral ends of tergites meeting in mid line, at most only 
slightly exposed and tergite venters slightly parted; g aedeagus long and slender and armed 
with a backwardly directed spinus (epiphallus) at junctions of the basiphallus and distiphallus 
(Text-fig. 22). 
The curious small tribe Doleschallini, which occurs in the Oriental Region 
eastwards to New Guinea and the Solomon Islands, has not been found in Australia. 
It seems just possible, however, that it might be represented in northern Queensland, 
and the tribe is therefore included in the following key to tribes. The Doleschallini 
includes the most slender elongate forms found in the Tachinidae and the adults 
are noteworthy for their habit of resting motionless (and well disguised) on the 
trunks of trees (especially coconut and, in New Guinea, Casuarina) with their 
exceedingly long spindly legs outstretched. 
KeEy To AUSTRALIAN TRIBES OF PROSENINAE 
[Note : Doleschallini is included although the tribe is not yet known from Australia. ] 
1 Abdominal Tr + 2 excavate to its hind margin. Thorax membranous medially 
or mainly so between bases of hind coxae and abdominal insertion, coxae and 
abdomen not unusually remote from each other. Head in profile not strongly 
subtriangular, as long at the epistome (or nearly as long) as at the level of the 
antennal axis. Head often with a strong facial carina. Notopleuron distinctly 
differentiated from the scutum by a groove or shallow depression. Body form 
usually robust, but if long and slender then abdomen broadest near base or 
subfusiform . : : : : : ‘ é : 2 
— Abdominal Tr + 2 encavate oaly at ne bie: Thorax closed above the hind coxae 
by a broad sclerotized bridge (as in Cylindromyiini), the hind coxae widely 
separated from the abdominal base. Head in profile subtriangular, profrons 
extraordinarily prominent and lower part of head strongly receding, head very 
much longer at antennal axis than at level of the epistome. Head without facial 
carina. Notopleuron not differentiated from the scutum by any depression. 
Body and legs excessively long and slender, the abdomen with subparallel sides 
(i.e. not distinctly fusiform or widest at base) . : : . DOLESCHALLINI 
2  Postalar callus with only the normal two postalar setae (at most only a weak setula 
in addition). Suprasquamal ridge and postalar wall bare. Epistome not 
produced in front of vibrissal insertions (Text-figs 29-30) or only slightly so 
(Text-fig. 27), usually not much visible in profile. Propleuron bare or haired. 
Barette bare or sparsely haired anteriorly (if all haired then no facial carina). 
Facial carina present or absent. Scutellum with three pairs of marginal setae 
(some supernumerary marginals differentiated in Rutilotriva). Male hypopygium 
without long strong erect setae on T7 + 8 (except in Acucera). Prosternal 
membrane and prosternum totally bare . 3 : . PROSENINI (p. 43) 
— Postalar callus with supernumerary strong setae, with a total of 3-6 setae (except 
in Chetogaster). Either suprasquamal ridge or postalar wall usually haired. 
Epistome subnasute or at least slightly and distinctly projecting in front of the 
vibrissal insertions in profile (Text-fig. 31). Propleuron haired. Barette thickly 

