Abstract
A new mutant, reddish eye (rd), was isolated from the Taipei strain of Aedes (Finlaya) togoi (Theobald), and has been found to be recessive and closely linked to the sex locus (or chromosome segment) m with a recombination value of less than 1%. This allele expresses itself only in the pupal eye with full penetrance and fairly constant expressivity, and can be used as a good genetic marker.