I figured as a Bombus mimic it would be a nectar feeder as an adult. Sometimes insects with such specialized equipment are pretty specialized. That proboscis might be about as long as a long-faced Bumble's tongue - which would make sense.
This is probably Bombylius Major and the adult is not specialized. The larva is a parasite of some solitary bees and wasps nests but again i don't think that it is specialized too much, the distribution would be smaller.