Anatomical basis of worm bursting at the vulva

Dear Worm Breeders,
I was hoping someone could shed light on the essentials of the worm burster phenotype. I have a mutant that reaches adulthood then bursts leading to the gut coming out of the vulva area. I used to remember there being a specific phenotype called Bst to describe this, but I can’t find anything about it on wormbase/book (maybe it was just lab lingo).
What is the anatomical basis of this phenotype? Is it failure to molt, or a fragile vulva? What are some mutants that give this phenotype? I’d also appreciate pointers to any relevant published literature.
Thanks
Ahmed Elewa

I am more familiar with protruding vulvae leading to rupture in some cases. I believe that a major cause is an abnormal vulval-uterine connection (see AP Newman papers), and thus stemming from abnormal or additional primary vulval lineages (e.g., lin-12(lf), abnormal anchor cell (e.g. fos-1.evl-5), etc. The rupture is a “terminal” phenotype, so look at L4 stage, and then look earlier if there is a defect there.

Thanks Paul … this was helpful .
AE