My praying mantises tail has been looking strange lately. Every once in a while it will almost fold over onto itself onto the mantises back. Is this normal? His appetite seems have to been very poor lately too. His tail will do that folding thing but then when I check on him a few hours later its back to normal. His had a fly in his enclosure for the past few days and I think he just finished a molt the other day because I see his shell on the bottom of his cage. Any ideas?