ebo⁶⁷⁸ mutant flies exhibit a normal external appearance. However, the ellipsoid body (EB) is split in two in 50% of ebo⁶⁷⁸ mutant flies. The fan-shaped body (FB) also appears to be vertically divided in the middle.

Tethered ebo⁶⁷⁸ mutants fly readily and for extended period of time which may be longer than in wild-type. Average torque traces and optomotor response appear as in wild-type. Torque spike rate is only slightly, and not significantly, reduced in these mutants. The amplitude of the small torque oscillations in between spikes is also reduced. The size and shape of torque spikes in these mutants are not noticeably abnormal. ebo^KS263 mutants exhibit normal optomotor response dynamics.

In a closed-loop with a single stripe (flight simulator), ebo¹⁰⁴¹ mutants behave close to normal. For over 85% of their flight time they keep the stripe in a frontal (+/- 15[o]) position.

Mutants have impaired visual pattern memory.

Show normal ability to develop ethanol tolerance.

Mushroom body defects are similar to ebo⁶⁷⁸. The ellipsoid body is open ventrally, flattened and occasionally divided. The fan-shaped body is split in many flies.

Females display increased ovulation and low receptivity after Acp70A injection.

Flight behaviour shows reduced amplitude in the small random oscillations of the torque trace (yaw torque activity). The frequency of torque spikes is significantly reduced (torque spike frequency). Flies behave close to normal in a single stripe flight simulator (on-target fixation). Gyandromorphs demonstrate the behavioural phenotypes yaw torque activity and torque spike frequency are all highly correlated with the phenotype of the ellipsoid body.

Ellipsoid body usually open ventrally (kidney shaped or horizontal bar shaped) and may dissociate. Phenotype of ebo¹⁰⁴¹ stronger than that of ebo⁶⁷⁸, which in turn is stronger than ebo^KS263.