The subfamily Pachygronthinae contains two genera within the limits of the United States, each with two well established species. Little is known of the life history of any species and none of the immature stages has been adequately described in the literature. This paper discusses three species: Phlegyas abbreviatus (Uhler), Oedancala dorsalis (Say), and Oedancala crassimana (Fabricius). The paper includes descriptions of all available immature stages with keys to the genera and species and means of separating the various instars within the species
