In the case of the cage-fly, the neck produces long spines that fold back and reconnect to the body, forming a protective cage. With the cage, the fly is too large to be swallowed by all but the largest predators. The cage also absorbs much of the impact from collisions. Because the mouth is so deep within the cage, this fly has an extended tongue (F) for feeding. (A) is the abdomen, (B) is the thorax, (c) is the wings, (D) is the hox-neck, and (E) is the head.
Notes: After drawing this, I thought the two rings of cage spines should really overlap each other at point (D), the front collar sending the spines backward and the back collar sending the spines backward. As it is now, the neck is a vulnerable point. Also, I thought the cage should be more symmetrical and wider in the back to make more room for the wings. The creature has no legs and rests on its cage.
Reader Challenge: What are all the types of things these creatures eat?