In the comments, Ted observes astutely:

Okay, I have to ask – do you give your subjects a “bath” prior to photographing them? I’m thinking in particular of the caterpillar hunter – there’s not a speck of anything on him. I think I just figured out one of the keys to your superb photos.

I noticed a while back that insects shot in the home studio were a good deal dirtier than insects shot out in the field. How could this be?

Most insects are meticulously clean animals, constantly stopping to groom themselves and remove bits of crud from their bodies. In the wild I don’t as often encounter dust-encrusted insects unless grubbiness is a regular part of their natural history. And regardless, I feel a loyalty in those circumstances to capturing scenes as I see them rather than grooming them down to a cleaner abstraction.

The trouble comes when transporting insects to the studio. I use a vial or old plastic food container, usually with a bit of moist paper to keep the humidity at a healthy level. Confined to such a small space the animals have a harder time keeping up their standards of hygiene. Dust sticks to everything. Vials roll and tumble in transport. Paper fibers cling to body hairs. And the poor insects emerge from their trip looking rather more disheveled than when they started.

So yes. I almost always clean animals before the indoor shots. It’s a simple process. By holding a leg between my fingers I can keep an insect still long enough to give it a few puffs with the same air blower I use to remove dust from camera lenses. Or I just co-opt my aspirator by operating it in reverse. A couple seconds later the insect is clean and ready to shoot.