My Facebook page post yesterday contained a photo of a female Broad Centurion, and here for completeness is her other half. The books would have you believe that you can tell the difference by their colours – while they both have a greeny-gold thorax, her abdomen is generally said to be blue, or even purple, while his is gold. To some extent this is dependent on the quality and direction of the light though, so I’d recommend a far more reliable way of telling them apart: his eyes join on the top of his head (think monobrow), but hers are separated. Male and female are both about 9mm long.
When I first ran across the term ‘soldierflies’ I assumed that they were named for some aspect of their behaviour, and I was (and still am, really) bemused to discover that the name merely relates to the fact that many of them have a metallic sheen, and might therefore be thought to be wearing armour. Among people with over-active imaginations. I’m not sure who originally coined the term, but it seems to go back at least to the early nineteenth century, and some variation of the same idea is used in naming this group of species in other European countries too.
Here we have forty seven recognised soldierfly species, all bearing common names that reflect their ‘military’ status. If I’m honest I find this slightly twee, but no-one asked for my opinion when they were assigning the names. Some of our species are much bigger and far more spectacular than the neat little Broad Centurion, but many are coastal, marsh, and fen specialists, so unlikely to be seen in a West Midlands garden. I did trip over an Ornate Brigadier recently though, beside the small pond at Grove Hill in Warwickshire, so it’s worth keeping an eye out for interesting-looking flies in the vicinity of ponds and lakes.
The indefatigable Steven Falk has catalogued all the British soldierfly species, to save you the trouble of doing it yourself. And if forty seven species aren’t be enough to keep you occupied, you can always start working through the other ten related fly families that fall under the umbrella term “Soldierflies and Allies”. That should keep you out of mischief for a while.