On the right is the butt end (i.e., the spiracles) of a Sheep Nose Bot (Oestrus ovis) larva, which makes its home in the warm, snotty nasal passages of sheep. When the larva has matured, it falls to the ground, burrows into the dirt, and pupates. The pupa hatches into an adult fly, which (while flying) deposits larvae directly into the nostril of the sheep.
Additional images of the Oestrus ovis larvae can be found on my website, The Monster Hunter's Guide to Veterinary Parasitology:
http://www.veterinaryparasitology.com/oestrus.html
- Ludo vs. Oestrus ovis.jpg (141.95 KiB) Viewed 1807 times