26 R. W. CROSSKEY 



upper calypter. The smaller dorsal one of the pair of membranous lobes at the 



wing base (alar squama) . 



This has little use in taxonomy but is of note in Prodiaphania (tribe Rutiliini) 

 in which, when the wings are closed, it is as long as or almost as long as the 

 lower calypter. In other Tachinidae it is normally much shorter. 



venter. The lower surface as a whole (especially of the abdomen). 



vertex. The upper surface of the head between the eyes and around the ocellar 

 triangle (Text-figs i & 2). 



This area is precisely delimited laterally by the eyes but it is rather vaguely 

 defined from the frons and occiput. The width of the vertex varies greatly 

 according to how closely the eyes are approximated and is typically wider in 

 females than males. The width when seen from above in relation to total head 

 width provides important specific differences. When the head is fully holoptic 

 (e.g. in some Palpostomatini) all that remains of the vertex is a prominent 

 ocellar tubercle (see ocellar triangle) . 



vestiture. Setae and hairing collectively. 



vibrissae. Paired setae inserted anteroventrally on the head at the lower ends 

 of the facial ridges and directed forwards (Text-fig. 3) . 



Typically the vibrissae are extremely strong and curve forwards and inwards 

 like a pair of tusks; often they are the strongest setae borne on the head. In 

 some forms they are reduced and scarcely distinguishable from the peristomal 

 setae (below them) or from the small setulae on the lower ends of the facial 

 ridges (above them). Short stubby non-crossing vibrissae occur in some forms. 



vibrissal angles. The corners of the head, typically rather prominent, on which 

 the vibrissae stand (Text-fig. 1). 



vibrissal axis. An imagined horizontal line through the head profile at the level 

 of the vibrissal insertions (Text-fig. 14) . 



vitta. A longitudinal band or line on the dorsum of the thorax or abdomen. 



vittate. Marked with vittae. 



wing venation. The rigid veins that support the wing membrane collectively. 

 This provides many important taxonomic characters at several levels, 

 according to the proportions shown by different vein lengths, the fusion or 

 non-fusion apically of R i + 5 and M v the position of the bend of vein M in 

 relation to the wing margin, the evanescence of parts of veins (especially loss 

 of M x ), the positions at which long veins abut on the costa, and to whether 

 certain veins reach or fail to reach the wing edge. In addition the extent and 

 presence or absence of setulae on certain veins can provide useful characters. 

 Setulae may occur on veins R v R i+5 , or Cu 1 but not on the other long veins 

 and never on the cross- veins; they are usually more extensive when present 

 on the upper surface of the wing but may occur ventrally also on R x and R 4 + 5 

 (especially on the node). 



KEY TO AUSTRALIAN SUBFAMILIES OF TACHINIDAE 



The satisfactory classification of the Tachinidae into subfamilies is a matter of 

 great difficulty and specialists are still far from agreed on the number and scope 



