Lycaenid Caterpillar

Description:

I didn't know what to make of this larva when I found it on the upper side of a leaf, almost exactly matching the color and texture of the leaf, except that it was covered in short fine white bristles. It was impossible to tell which end was the head and had no visible legs or prolegs. I took pictures of it during the day (pictures 5 and 6) in which it was immobile in the center of the leaf. I took more pictures of it after dark and by then it had moved to the edge of the leaf to feed (where it had obviously been feeding the night before) (first 4 pictures). After a bit of searching, I find that this is the larva of a Lycaenid butterfly, probably one of the hairstreaks. These are notoriously famous for varying types of associations with ants, from mutualism to parasitism (some species even feeding on the ant's larvae within their nests). These larvae possess Tentacular Eversible organs on the tail end of the larva which emit chemical compounds for communication with ants. (These are just visible in the last picture as tiny white bumps on the third to the last segment). They also have a Dorsal Nectary Organ one segment above the Tentacular organs which is used to feed ants in mutualistic relationships in which the ant receives food in exchange for protection from predators. During the various visits I made to this larva, I never saw any ants anywhere near it. I've listed several fascinating references for the behavior of Lycaenid larvae. Another fascinating aspect about these larvae is that many species (if not all) produce sound (such as stridulations or squeaks) which also aid in their communication with ants through the leaf surface. The sounds are not audible to the human ear. There are also Pore Glands scattered over the surface of the body of the larva which are thought to alert ants to the fact that the caterpillar is not a prey item, maybe through a chemical type of appeasement signal. I believe these pores are visible on this larva as very tiny red dots. It was about 1 cm long. Family Lycaenidae. As an unrelated aside, a tiny (about 1 mm) green Leaf Beetle passed over the top of the larva (5th picture). I've never seen that particular Leaf Beetle before either.