Descriptions of the Nymphal Stages of Some North American Pentatomidae (Hemiptera-Heteroptera)

A study of various instars is presented as an aid to identification. The external morphological characters of nymphs are discussed, and a detailed description is given of each instar (with very few exceptions) of the following 16 species: Euschistus variolarius (P. de B.), E. euschistoides (Voll.), E. tristigmus (Say), Mormidea lugens (Fabr.), Coenus delius (Say), Menecles insertus (Say), Trichopepla semivittata (Say), Neottiglossa sulcifrons Stål, Peribalus limbolarius Stål, Pitedia persimilis Horváth, Thyanta custator (Fabr.), Cosmopepla bimaculata (Thomas), Oebalus pugnax (Fabr.), Acrosternum hilare (Say), Podisus maculiventris (Say), and Perillus bioculatus (Fabr.). At least one instar each of 14 of these species is illustrated.