Two kinds
Mossflits flush into the air when you get close, and may bite if hurt. Cinderfangs defend their roost: they circle, screech, then dive at you in runs, and they give up if you walk away from the roost.
Under tall roofs some colonies are Dripwings, which go for your torch.
Dealing with them
Listen for the screech and sidestep the dive, or just walk off. Standing still and quiet in the dark draws them less.