Bombus Mystery, back, roulston, va

And now we present a mystery. Here is a bumble bee collected in northern Virginia in a blue vane trap as part of T'ai Roulston's research group looking at bee populations in restored fields. The question at hand is what species is it? Its a clean, unworn bee, appears to be the size of large worker or perhaps a small queen and it fits some characteristics of B. affinis (endangered species!..) and on the other hand it fits some characters of B. rufocinctus (no validated records for MD, VA, WV, or NC...a recently validated record from NW PA). Things to note...Face has all black hairs (B. rufocintus usually has yellow hairs at the top of the head), ocelli are clearly recessed below the tops of the compound eyes (characteristic or queen B. rufocinctus, but I think not for B. affinis), Has characteristic hair pattern on top of abdomen for B. affinis ...except that there are extensive, and symmetrical patches of black hairs on the lateral sides...somethings that I have never seen in B. affinis (B. rufocintus is extremely variable in hair, but perusal online shows no hair patterns exactly like this one...usually there is much more extensive amounts of light colored hair throughout the abdomen. OK, your turn...what do you think it is and why?