|The marmalade hoverfly, Episyrphus balteatus, on Meconopsis cambrica in the garden|
I freely admit that I'm no insect expert but my training as a zoologist / ecologist does allow me to use taxonomic keys to roughly identify most of the larger insects down to family or even genus level. After that I'm reliant on the quality of my photographs to pick out identifying features which can help in the trawl through Google images and other resources to identify particular species. So it is with hoverflies.
Beyond a vague knowledge that there are quite a few different species in the UK (about 250), that many mimic wasps and bees in their protective coloration, and they act as efficient - if indiscriminate - pollinators I'd never really looked at them in any detail. By 2010, however, I'd put together the macro flash rig I illustrated in the previous post and was looking for subjects. And hoverflies suddenly swam into focus.
I don't specifically garden for pollen feeding insects but I do grow a lot of plants that provide abundant sources throughout the warmer months. Which means the garden is a good source of subjects. I also live close to one of Plymouth's suburban nature reserves and walks through there are usually productive. So it was that I started to put together quite a few photos. And then the ID problems started.
Some were easy. Episyrphus balteatus, the marmalade hoverfly, is pretty distinctive in its orange and black markings. Equally easy to ID was the long snouted Rhingia campestris. You can't really mistake it for anything else - even though I only saw it once and only managed a single shot earlier this year and I often need a few for ID purposes.
|Rhingia campestris in the local nature reserve|
|Helophilus pendulus in the garden|
I'd like to think I was working to that philosophy when I took this capture of Myathropa florea feeding on my Sedum spectabile earlier this year. It's not one of my better shots - but I could easily have ignored the hoverfly thinking it was one I'd already photographed.
Then there are the hoverflies that are relatively easy to identify to the genus level but after that it's a nightmare. Sphaerophoria is a case in point. Fifteen British species and the only one that can be identified with certainty from photographs is the long bodied male Sphaerophoria scripta. The one below is female - you can tell from the wide separation of the compound eyes, males are narrowly separated - but apparently they can only be correctly identified from microscopic differences in the genitalia. So, much as I would like to identify this one as Sphaerophoria fatarum - the markings match - I can't.
|Sphaerophoria sp. Possibly S.fatarum|
|Apis mellifera, the honey bee the two Eristalis are mimicing|
|Syrphus ribesii (t), Eristalis pertinax (r) and an unknown small species on Meconopsis cambrica|