Perhaps a blister beetle, Meloe sp.. Their adult-like larvae crawl up
   into flowers, where they wait for a bee, then attach, return to the
   bee's nest, drop off, moult to a more typical "grub" larva, feed, and
   mature. I think these are native species, adapted to some native bee.
   Perhaps a Bombus expert will know.
   Some attach to honey bees. We've found them in our external mite
   detection surveys, but I've never seen one as big as 4 mm. I'd be
   interested to hear of what you find.
 
 
   Kerry Clark, Apiculture Specialist
   B.C. Ministry of Agriculture
   1201 103 Ave
   Dawson Creek B.C.
        V1G 4J2  CANADA          Tel (604) 784-2225     fax (604) 784-2299
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