ebiP7/ebiE4 wings are 86% the size of control wings. Gross defects in wing patterning are not apparent. There is no significant decrease in the size of other organs or the whole organism.
ebiP7/ebiE4 larval wing discs have visibly smaller wing pouches.
No or very few ebiE4 clones survive to late third instar stage when induced at 48 hours after egg deposition (AED), and survival is not improved by inducing clones in a Minute/+ background. Clones induced at 72 hours AED do survive, but are very small.
The average number of crystal cells per embryo is reduced in homozygous stage 13-14 embryos compared to wild type.
In ebiE4/ebi7 animals at the non-permissive temperature a loss of cone cells is seen. When homozygous ebiE4 clones are made in the developing eye, these mutant cells can differentiate into cone cells when they have wild-type neighbours.
Mutant embryos exhibit a tail up or U-shaped phenotype, with head defects. When there is no maternal contribution of ebi+ gene product, the embryos have a more severe phenotype, including a tightly curled morphology and the loss of ventral denticle belts. Severe head defects also occur. In contrast to Egfr mutants, some residual cuticular structures remain. Filzkorper are present but malformed. In mutant clones in the eye, each ommatidium contains a single R8 cell, and early clusters appear normal. Clusters containing 8 neurons do form, but disorganised clusters with fewer differentiated neurons also occur. Generally R cell number is reduced, though R7 cells do develop, and 80% of R cells show altered cellular morphology.