Hi, do you see that strand coming from the pupa? That is what the parasite came out of the pupa on. I have seen this with the parasite sturmia bella. This is what i think will have killed your pupa. It crawls out as a grub and pupates, then after two weeks hatches into a fly.
Hi! Thank you for answering my question. I am sad that now I only have three pupa left but I already thought so... Do I have to remove the dead pupa or can they stay? I don't want to disturb the other ones if possible and they all are hanging from the same wood thing (don't know what to call my creation made of take out chopsticks).