“Reduced appendage”: A mutation affecting development of pupal and adult appendages of the moth, Plodia interpunctella

A mutant that results in the reduced length of pupal and adult appendages was isolated from a laboratory colony of the Indianmeal moth, Plodia interpunctella (Hübner). “ R e d uced appendage” ( rda ) was determined to be an autosomal recessive mutation that affects the development of pupal and adult appendages during the larval/pupal molt. The rda mutation had no observed effect on the larval phenotype. After pupation, the appendages of rda were reduced in size as compared with wild‐type. In addition, unsclerotized cuticle underlying the pupal appendages was exposed and the establishment of the boundary between the unsclerotized and sclerotized pupal abdominal cuticle appeared normal even though the imaginal discs of rda did not evaginate normally. This demonstrates that rda affects only imaginal discs and that the morphogenesis of structures that were not derived from the imaginal discs were not dependent on interactions with evagination of imaginal discs. Although the rda phenotype resulted in shorter antennae, mouth parts, legs, and wings in pupae and adults, the mutation did not affect the number of cells comprising the imaginal discs or the pupal appendages. Cell counts showed that forewing imaginal discs and pupal forewings from the rda mutants contained the same number of cells as did the imaginal discs and wings from the wild‐type strain. Thus, rda appears to affect processes related to disc evagination and not cell proliferation. © 1994 Wiley‐Liss, Inc. This article is a US Government work and, as such, is in the public domain in the United States of America.