Flies have a mutant ellipsoid body.
When originally isolated, homozygous adults had a ventrally opened ellipsoid body in the central brain with strong penetrance. The penetrance became very strong after 5 generations of outcrossing. cibP/Df(1)A113 flies have an opened ellipsoid body with very high frequency. Heterozygotes have no adult central brain defect.
cibP has ellipsoid body phenotype, enhanceable by chic[+]/chic221
chic221, cibP has fan-shaped body phenotype
chic221, cibP has mushroom body medial lobe phenotype
chic[+]/chic221, cibP has fan-shaped body phenotype
chic[+]/chic221, cibP has mushroom body medial lobe phenotype
cibP/+ ; chic221/+ double heterozygotes show a cib-like mutant phenotype, with a partially split fan-shaped body (it is split along the midline in 10% of flies), a ventrally opened ellipsoid body and a normal mushroom body. This interaction is synergistic. Addition of chic221 to cibP/Y flies exacerbates the cibP phenotype; cibP/Y ; chic221/+ males have a fan-shaped body that is split in the middle, a strongly disturbed ellipsoid body (it is flat and very often split along the midline) and disorganised mushroom body medial lobes that rarely reach their normal position. cibP/Y ; chic221/+ males are also sterile and show a thoracic bristle defect with shorter and forked ends than normal.