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TACHINIDAE OF AUSTRALIA 19 
Tachinidae but has taxonomic importance as a taxonomic feature in a few 
forms in which it bears long dense hair (e.g. Microtropesa and Paratropeza). 
pollinose. With a covering of pollinosity (q.v.). 
pollinosity. A nap-like covering to any part of the body formed by closely 
aggregated ultramicroscopic pubescence. 
The extent, density and colour of pollinosity can provide taxonomic characters 
and are largely responsible for the general appearance of many Tachinidae. 
Banded or spotted patterns are typically produced either by islands of dense 
pollinosity surrounded by less pollinose areas, or alternatively by non-pollinose 
islands in areas that are mainly thickly coated with pollinosity (e.g. the 
conspicuous spot patterns of Amphibolia). When pollinosity is not evident 
at normal magnifications of the entomological microscope (up to X I00 or x 150) 
or is very inconspicuous on any area then the area is said to be ‘non-pollinose’. 
When the cuticle is dark, non-pollinose areas are typically metallic and the extent 
of metallic colour can be important taxonomically (e.g. in Rutiliini). 
postabdomen. The part of the abdomen including the terminalia lying beyond 
segment 5 (the last segment normally readily visible). 
In many forms much of the postabdomen is concealed and tergite 5 forms 
the end of the immediately visible abdomen. In some forms the postabdomen 
is more conspicuously developed than normal and may be distinctly recurved 
under the main part of the abdomen (preabdomen) (e.g. Cylindromyiini) and 
may bear elaborate modifications associated with oviposition (e.g. various 
forcipate processes in female Phasiinae). 
postalar calli. The paired convexities forming the posterolateral corners of the 
thoracic dorsum (Text-figs 4 & 7). 
postalar setae. The strong horizontal setae standing on the postalar calli 
(Text-fig. 4). 
In nearly all Tachinidae there are two strong postalar setae, but in all 
Rutiliini there are three or more (sometimes as many as six or seven) strong 
postalars, the distinction between three, and four or more, being very important 
in taxonomy of the group. Outside of Rutiliini the development of a strong 
third postalar seta is rare (but occurs, e.g., in some Microtropesa). Rarely only 
a single strong postalar seta is developed (e.g. in some Phasiini). 
postalar wall. The vertical declivity forming the outer surface of the postalar 
callus (Text-fig. 7). 
This area is of taxonomic value in the Rutiltini where the postalar wall bears 
a dense tuft of hair in Formosia and Formodexia Crosskey that is absent in 
other genera. These genera appear to be the only forms represented in the 
Tachinidae with such hair (in all others the postalar wall is bare or at most has 
only one or two hairs on its extreme upper part immediately below the rounded 
haired outer lip of the callus). 
_postbucca. A vaguely defined area between the gena and the occiput forming 
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the posteroventral corner of the head (posigena) (Text-fig. 1). 
posteroventral declivity of the thorax. That part of the thorax laying between 
the base of the abdomen and the insertions of the hind coxae (Text-fig. 7). 
