NEW MUTANTS AND THEIR CHROMOSOME ASSIGNMENT IN THE FLY MEGASELIA-SCALARIS

We describe six new mutants, spontaneous or EMS-induced, and a previou sly isolated radiation-induced mutant of Megaselia scalaris Loew (Dipt era, Phoridae). Five are eye-color mutants, one affects the segmentati on of the abdomen, and one disturbs the regular form and arrangement o f ommatidia in the compound eye. A complementation test exposed two pa irs of alleles among the five eye-color mutants, leaving three differe nt loci that affect eye pigmentation. Two of them influence the amount of xanthommatin synthesized, and one blocks the ommochrome pathway at the kynurenine step. We established chromosome assignment of the muta nts by crossbreeding them with Y chromosome-autosome translocation str ains.