The fangs of a botfly
I must admit I am responsible for harboring an alien species (via Belize last month)... the human bot fly, Dermatobia hominis... I have four... #2 son decided to be a bigger pain than usual (each of them feeds inside my leg about two to three times per day) and started to emerge so with a friendly squeeze, out he popped as a late 3rd instar (head is left, posterior spiracles right, the black specks are backwards projecting spines).
I had five originally, one definitely euthanised (hot sponge, big squueze!), and I thought I'd also removed two more to just keep two, but it appears that in those two warbles, room-mate larvae were still there! So now I still have three at different stages, another 3rd instar and two perhaps still at 2nd.
the only real pain is like sharp needle pricks inside the warble, lasting a few seconds each (they refuse to be courteous and feed at separate times!), immediately followed by a stream of blood from fresh wounds or they expel clotted tissue or escahr that interferes with their breathing.
actually it's kinda cool- the female bot fly captures a mosquito and deposits her eggs inside it... as soon as the mosquito takes a blood meal (ie. me!) the eggs react to the temperature change and hatch and then the larvae burrow down into the bite wound to feed and grow... after a few weeks the larvae eventually emerge, drop to the ground and pupate and about 2 weeks later the next generation of fly emerges to mate and then start the whole process over again... I have three left inside me so I'm hoping I can grow one of them to the fly stage.
UPDATE: I'm a dad again! After 15 weeks feeding off me as a larva inside my leg and then another 4 weeks as a pupa underground, I gave birth yesterday!