Larval behavioural phenotype: homozygous larvae have very low sensitivity to touch. Homozygous larval motility is severely reduced. Adults are barely able to walk and die by adhesion. Homozygous larval also exhibit frequent turning and gynandromorph mosaics exhibit severe uncoordination. Nervous system morphology is indistinguishable from wild type. At a high transepithelial potential (TEP) the mechanoreceptor potential (MRP) is reduced, but not eliminated.