Swallowtail chrysalides struggling to emerge

[Crake]

Hi everyone.

I've got a couple B. philenor hirsuta pupae that have started emerging recently, but several of them seem unable to fully eclose. They've developed as usual, with the chrysalis becoming transparent prior to emergence, bu then they just stay that way. They don't emerge, and they eventually die. I had one individual make it out but with crippled wings, which has been the leading factor in my theory that this has something to do with moisture, but I'm not entirely certain this is the case.

Has anyone observed this happening before?

Thanks.

[exoticimports]

Spray them with water?

It occurs naturally, I got a philenor this year that
Had a crinckled HW.

Chuck