I heard about your site in German TV and so I remembered a photo I’d taken in 2006 in Sweden. That little bug is “torturing” a bumble-bee by pinching its proboscis. Can you tell me what ‘s happening there? Kind regards
You are the second letter we received today that mentioned seeing our site on television. Our first job is to identify your beetle. This appears to be a Flea Beetle in the tribe Alticini, but we would like verification. Hopefully, Eric Eaton can substantiate that. This diminutive beetle cannot possibly think the bee is food, but it might be hitching a ride, a phenomenon known as Phoresy. We hope to get clarification on that from Eric Eaton as well.
That is a really remarkable shot of the beetle clamped onto the bumble bee! It is not a flea beetle, or any other type of Chrysomelidae leaf beetle as far as I can tell (flea beetles get their name from their ability to jump, not because they are parasitic). I suspect it is some kind of sap beetle (family Nitidulidae), some of which can be abundant inside flowers.
I think I have a proper guess what sort of a beetle this might be! It belongs to the genus Antherophagus (fam. Cryptophagidae, silken fungus beetles), which has three species in Sweden, all developing in nests of bumble bees. I think this one is A. pallens (Linnaeus, 1758) (~4 mm), which is the most common species of the genus. All species visit flowers to clamp onto bumble bees to hitch a ride and infest their nests. But the larvae are supposed to be harmless to their hosts, feeding on the bees’ faeces. So this is a perfect example of a picture showing the start of a Phoresy! Best,
Bengt Andersson Sweden