P element is inserted at 31.
Onion stage early spermatids in homozygous males either lack or have only tiny mitochondrial derivatives. Flagellar axonemes elongate without mitochondrial derivatives. Mitochondria are present in polar primary spermatocytes, but degenerate prior to meiosis in mature primary spermatocytes.
nmdry4/nmd[+] is a suppressor of wing margin phenotype of Bx1
Berg, McKearin and Spradling