Bombus soroeensis?

JRsbugs · #1 (**permalink**) 06-09-2011, 11:31 PM

OK, I know we need to see the mandibles and that is reasonably visible in one shot of the possible queen, I can't quite work out how they work with the black with white between, it doesn't fit in with where the notch should or should not be! There looks to be several black 'tooth' shapes with stretchy white areas between extending from those.

The worker was no more than 12mm, feeding on white clover. Within half an hour there was a bigger bee which looks like a queen near the same spot and was ~16mm, she had stopped for a quick clean. I got the worker the following day in the same place, and saw it the previous day.

These don't look like any B. lucorum I have seen, but I had a bee similar in 2008 feeding on Heuchera which was more worn and looked like this. These aren't very worn, and I doubt the yellow band on the abdomen would be eroded in the middle.

Taken mostly on 9th July.

Worker..

Queen..

Matt Smith · #2 (**permalink**) 07-09-2011, 09:47 AM

The queen appears to be a B.lucorum queen, there is no yellow in the sides of T1. For the mandibles, we really need to see the tip to check for a notch or not, but the presence of the 3 "dark lines" are indicative of ridges or carina on the mandibles which B.soroeensis doesn't have.

The worker looks to me like a wet and tatty B.lucorum worker - the yellow bands do wear. I have picked up countless "broken banded" bumblebees over the years and on examination not one of them has turned out to be a female B.soreensis.

JRsbugs · #3 (**permalink**) 07-09-2011, 11:39 AM

Thanks Matt, that was my gut feeling as I couldn't see any yellow at the sides of T1 either.

The mandibles are strange, I have seen the whitish areas in others but not sure what they are constructed of, is it solid or does it have stretchability.

The worker wasn't wet, it was quite well haired. I wonder if this is the 'possible' 4th species in the B. lucorum complex which Stuart mentioned not long ago..

I found someone's blog about the species complex in Canada..

The Home Bug Garden: Bumbling with Bombus: the late lucorum

A pdf giving more info, B. sporadicus is one included in the complex of 5 species which also includes B. terrestris. Would this be the suspect 4th species in the lucorum complex?

http://www.sbes.stir.ac.uk/people/go...sDiversity.pdf

Matt Smith · #4 (**permalink**) 07-09-2011, 12:21 PM

Quote:

Originally Posted by JRsbugs

The mandibles are strange, I have seen the whitish areas in others but not sure what they are constructed of, is it solid or does it have stretchability.

The white on the mandibles is essentially "gunge", either soil or pollen or something else stuck on the surface of the mandibles between the ridges.

Quote:

Originally Posted by JRsbugs

The worker wasn't wet, it was quite well haired.

If not wet, at least damp - look at the clotting of the black hairs highlighted against the yellow of the collar in the photo of the bee facing away from you.