Occurrence of a Pupal Melanization Reducing Factor in Different Insects

Abstract

A pupal melanization reducing factor (PMRF) controls incorporation of pigments into the cuticle of pupae of the nymphalid butterfly, Inachis io, to adapt their coloration to the background colors of their pupation sites. In the present paper, we report on the presence of PMRF in the central nervous system (CNS) of further butterfly species which exhibit a pupal morphological color adaptation. Interestingly, two butterfly species which do not show such an adaptation, and even two moth species which pupate in cocoons also contained PMRF in their CNS. The ganglionic extracts of non-lepidopteran species did not show a PMRF activity. The occurrence of PMRF (or PMRF-like molecules), therefore, may be restricted to the lepidopteran order