A couple of days ago I found a bee at Great Chalfield that I couldn’t identify. Dark-winged, with a dark abdomen with narrow silver/white bands it was nectaring on Cow Parsley. To be totally honest I had no idea what it was, so I took as many photographs as I could before it moved on. After looking at images on the excellent Bee, Wasp, and Ant Recording Society (BWARS) website I was none the wiser though. The UK has some 300 bee species, and many of them are very similar indeed. My bee looked like any number of other bee species and I wasn’t really sure what I should be looking for to separate them anyway…
Oh well, when in doubt, ask an expert – and the BWARS site not only has a wealth of great information it has a very active forum watched over by some very knowledgeable (and extremely helpful) entomologists indeed.
A request for ID help quickly elicited a response from both Jeroen de Rond and Janet Pick. I’d uploaded the images below to a folder on BWARS which they’d looked at. Opinion though was divided between Andrena chrysoceles and Helictus rubicundus – two species I knew nothing about, but which appeared remarkably similar from online images when I checked.
The conversation went back and forth until Jeroen asked whether I had any photographs which showed the wings. There is, he said, a distinctive bend in one of the veins (the Median or Basal vein) in Helictus bees that is lacking in Andrena. Two images he sent showed the difference very well: one vein was strongly bent before joining the vein below it, the other (the andrena) showed more of a smooth curve.
Andrena wing venations, median/basal vein highlghted. Image courtesy of Jeroen de Rond.
Helictus wing venations, median/basal vein highlighted. Image courtesy of Jeroen de Rond.
I checked if I had taken a suitable image, lightened one of the most likely photos I’d taken in Photoshop – and it showed quite clearly a smooth curve (see below). ‘My’ bee was definitely an Andrena. Additionally, Jeroen added, the reddish colouring of the veins identified the species: it was indeed A. chrysoceles.
Andrena chrysoceles wing venations, median/basal vein highlghted
It’s quite remarkable, don’t you think, that it’s possible to identify bees to family level purely on the strength of the shape of one wing vein. Diagnostic vein patterning is not confined to bees though. Hoveflies, it turns out, have a distinctive pattern of venation that distinguish them from other flies. On top of that many insects (micro moths for example) can only be identified by examination of their tiny – and unique – genitalia. It’s extraordinary. Extraordinary that anyone noticed these often subtle differences, but surely even more extraordinary that those differences ever evolved in the first place…
Photos copyright Charlie Moores/Talking Naturally 2012 except were indicated.