Saturday, March 31, 2012

Bee-fly - Bombylius discolor

This is a photo of two of our Bee-fly species from Stubbs & Drake's British Soldierflies & Their Allies' excellent identification guide. The relatively rare Bombylius discolor is centre-left, and the very common Bombylius major is centre-right.

For years I have examined hundreds of the common Bombylius major Bee-flies in Bedfordshire hoping to come across Bombylius discolor....but to no avail. Here on the Isle of Wight there have been large numbers of Bombylius major Bee-flies holding territory and buzzing all over Golden Hill Country Park in the sunshine over the past week...but no Bombylius discolor, though I have been told that the latter are fairly common on the Island.

Then today, at Walter's Copse, Newtown, I came across this during a brief patch of warmer weather:

Bombylius discolor....yahay!!! :-) :-) :-) The spotty wings present in this species are quite obvious.

I spent the next few minutes observing the fly nectaring on Primrose, it's amazingly long proboscis reaching right to the base of the petal tube as this video shows:

The long mouth-parts mean that it's not receiving any pollen in exchange, so the flower is probably being cheated! (There were also Platycheirus albimanus hoverflies feeding at the flowers - they would have been unable to reach the nectar but would be specifically after the pollen!).

What I will be looking out for now is the amazing sight of the female Bee-flies flicking their eggs onto the ground where the larvae will crawl into solitary bee holes and parasitize the larvae. These species of Bee-fly even have a sand-chamber at the base of their abdomen which they use to coat the doubt giving them a bit more weight for launching and, maybe, to give the eggs a bit of camouflage and protection before hatching out!

Here's a bit more video to enjoy:

Notice that white stripe running down the centre of the backside! When the bees are in flight I reckon that might be an easier way for distinguishing the two species rather than trying to work out if the wings have spots which I have been seeking to do up to now.


  1. Fantastic videos of the bee-flies, Steve! Congratulations!

  2. Thanks, big invertebrate interest is hoverflies so I'm hoping to get some footage of these beautiful creatures as the season goes on!

  3. Saw a discolor today in Henlow, Bedfordshire I'm sure I've never seen one before.
    The white spots on the rump and your great video confirmed this. The white spots become an array in flight.