Homozygous 12-day old larvae show overgrowth of the brain, hematopoietic organs and imaginal discs and a reduction in size of the salivary glands. The size of the digestive tract is nearly normal.
Lethality occurs during third instar larval or pupal stages. Mutants exhibit visible disc abnormalities: very small or no discs. Clones cannot be induced in wild type discs.
Elongated brain hemispheres, slightly abnormal folding in discs, lymph gland retains lobular structure.