The Bristly and the Beautiful

Flies in Australia get a bad rap. I grew up in the era of the antihero, Louis the Fly, who came ‘straight from rubbish tip to you’. And I cannot count the number of times that flies have made an outdoor summer event less than ideal. However there are flies and then there are flies.

Rutilia sp.

Bristle Fly (Amphibolia vidua)

Last month Macwake published a blog on the Golden Headed Rutilia Fly (Rutilia argentifera). This fly is of a group known as Tachinid Flies. With the advent of summer a number of tachinids have been seen in the district. On first sight they look like any other fly but are distinctly bristly, hence the name Bristle Flies. Tachinids are generally larger than the common house fly and in the case of those photographed, much larger. The adults feed on nectar and the honeydew excretions from insects such as aphids and scale insects (not a rubbish tip in sight!). As Macwake noted, flies like these are important players in the pollination of plants.
 

Microtropesia sinuata

***WARNING – GRUESOMENESS AHEAD*** Most tachinid flies deposit eggs on a live host, usually the larvae of butterflies and moths. After a few days the eggs hatch and the maggots bury themselves into the host and proceed to eat it from the inside, eventually killing the host. For flies of the Rutilia genus, the eggs are laid on the ground and the hatched maggots dig into the ground looking for the larvae of Scarab Beetles which they parasitise. These flies are important controllers of pests and some species have been used as biocontrols.

Rutilia sp.

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A close examination of photos shows these flies to be both bristly and beautiful – just like (dare I say it) my partner’s legs…this may be my last blog!