Complete removal of the armi coding region in the Df(3L)armi-J deficiency line.
arminull mutant flies (expressing CycJ+t4 to restore CycJ[+] function) produce mature eggs that are often collapsed and that have dorso-ventral axis establishment defects. The arminull mutant ovaries have significantly fewer egg chambers per ovariole compared to wild type and show frequent mislocalisation of oocytes within egg chambers.
CycJ+t4, arminull has dorsal appendage phenotype, suppressible by lokp6
This deficiency has been used as a null allele for armi when in combination with CycJ+t4.