I have seen many of those bumble bee-like flies in Eastern Canada. In a
few cases I mistakenly followed one believing it was a Bombus impatiens
worker. These flies belong to the Syrphidae, which include some of the
most striking bee mimics. The Genus Mallota  and Voluvella  have
fine yellow hairs on the thorax and the basal portion of the abdomen that
resembles the pile of a bee, the
remaining hairs are black or entirely lacking. The fly closely resembles
a bumble bee worker. Mallota sp. and Voluvella sp.  are easily distinguished
from a
bee, because they have large compound eyes which meet dorsally, short
club-like antennae and lack of a pollen carrying basket.
        Bee flies (Family: Bombylidae) are easily distinguished from
Syrphids by a long proboscis which may be as long as the body.
 
 
                                                Best Wishes,
                                                Blair
 
Blair Sampson
Dept. of Entomology
Auburn University
Alabama 36849-5413
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