The consequence of these profound, developmental changes was that holometaboly immediately provided larval-feeding and adult-reproductive adult instars access to very different habitats that often were deployed in a seasonal or other spatiotemporally exclusive manner--thus allowing survival of both during mutually unfavorable conditions.

Among candidate taxa representing early, Pennsylvanian occurrences of holometaboly , Metropator and Fatjanoptera are probably most notable (Hennig, 1969; Stys and Soldfin, 1980).