Posted by Susan R Walter on 29-04-2007 19:14
#1
Apologies for the state of this specimen - it had a rather serious accident, as you can see:(. I wouldn't have bothered to post it, but it, and its brethren, were exhibiting some interesting behaviour a couple of weeks ago (14 April) in my front garden. This garden has a large patch of Lesser Celandine, and a healthy population of mining bees. These flies were taking a great interest in the Tawny Mining Bees
Andrena armata on the south side of the garden where the Celandine is thick. A
Nomada bee (presumably signata, as it is associated with
A armata) was also around.
I witnessed the Nomada going right down into the Tawny Mining Bee holes, apparently when the bee was absent. The flies though hung about the Lesser Celadine and 'tailgated' any passing Tawny Mining Bees, to what purpose is not clear. They apparently take a great interest in where the Tawny Mining Bee disappears (down its hole). I witnessed flies waiting at the entrance after a bee had entered a hole, and venturing into the mouth of the hole to about one body length, while the bee was still in residence. The bee stayed down in the hole and did not emerge to discourage the fly's activity.
The north side of the garden, which has a lot more bare earth and not so much Lesser Celandine, seems to be favoured by a different mining bee, maybe the Early Mining Bee
Andrena haemorrhoa. They do not seem to be pestered by either the flies or the parasitoid bee.
Unfortunately, just as I went for a shot of the fly and bee together and interacting, the batteries went dead on the camera:(
Does anyone know anything about this behaviour and can anyone identify the fly. I have tried keying it through Acland, but have had my usual lack of success with this key. (The key is fine, but complex, and I am not experienced enough to cope well with it.)
Posted by Susan R Walter on 29-04-2007 19:17
#3
Close up of the wing (well, since it's come off, might as well :p _
Posted by Susan R Walter on 29-04-2007 19:21
#5
The fly venturing into the
Andrena armata hole. The bee had gone down the hole a few moments before.
Posted by Kahis on 29-04-2007 20:09
#9
Hmm. The behaviour and the remains have me thinking of
Leucophora (Anthomyiidae). The larvae of these flies live as inquilines or brood parasites in bee nests.