Dagger fly

Empis livida

Right around this time of year, we start to notice dagger flies (aka dance flies) hanging around the composite flowerheads in the garden. The most regular of these is Empis livida, identified by its red-orange legs and the three dark stripes on its brown thorax (visible in the picture above). Females have clear wings (as below), while those of males are slightly cloudy. As you might guess from that wicked looking proboscis, this is a hunter-killer. It lurks around on flowers waiting to stab any unsuspecting insect that wanders by – though while it waits, it's more than happy to sip a bit of nectar from the flowers. They fly from April through July across much of England and Wales but are far less common in Scotland. Elsewhere, they're found throughout temperate and northern Europe, making them one of the most widespread flies in their genus. They've been shown to be quite effective pollinators, which isn't surprising, I suppose, considering their general hairiness (particularly on their legs) and their habit of hanging around on flowers. Their larvae are carnivorous, feeding on things they find in the damp soil and leaf litter where they grow to adulthood.