Entomology (Study of Bugs)/Swallowtail Caterpillar Dying
Can you please help me to figure out what may have happened with this little caterpillar? I have raised dozens of swallowtails and I have had this one since the beginning as he came in on some parsley I harvested. Since he was so tiny I didn't put him back outside because there were about 6 others who were full-sized in the parsley patch. So I kept him on the parsley inside, grown by me and untreated - same parsley everyone else is eating outside. He did all his molting and was nearly ready to form a chrysalis. Last night before bed I checked on him and he was fine and he was eagerly munching away on the parsley but when I got up this morning his whole back end was shriveled, gray and looked wet. I have included a picture. I would really like to know "what" happened so that if possible, I may prevent this from happening again.
Thanks in advance for any input.
The survival rate of insects is low. They are subject to attack from bacteria and internal parasites. I suspect that one of these is the cause here. I believe that a puncture of the skin before the last stage begins can also be at fault. I am sorry but I do not believe that you can prevent these events