"It is made more unusual as most nasal botflies directly lay their eggs into the nasal cavity. So the first instar stage uses its large mouth hooks and spines on its back to pull itself along from the eye to drop down into the nasal cavity. I have just tried looking up images for this and even for me, have decided that may be too much…..
It is generally found in large ruminants such as deer but can be problematic in sheep. It has been found in man although these cases are exceptionally rare I hasten to add. There was a case were large numbers of first instar larvae were deposited in the ear!!"