Imprecise excision of the P{lacW} element resulting in a deletion within the bl transcription unit.
viable (with HnRNP-Kv1)
visible (with HnRNP-Kv1)
leg (with HnRNP-Kv1)
wing (with HnRNP-Kv1)
blv1/blv2 flies are viable. The legs and wings are almost wild type in size (they are smaller than normal). The eyes are normal.