Abstract
Three new species of Meteorus parasitoids of Arctiinae are described: Meteorus anuae n. sp., M. juliae n. sp. and M. mirandae n. sp. The first biological record for M. cecavorum Aguirre & Shaw as well as its cocoon description is reported. A comprehensive key for the Neotropical Meteorus attacking Arctiinae is provided. A total of nine Meteorus species have been reared from Arctiinae in the Neotropical Region. Six of them are gregarious and three solitary. The biological information about host and food plants concurs with the hypothesis of specialist parasitoids preferring “nasty” caterpillars.