A reevaluation of the generic limits of Pnigalio Schrank (Hymenoptera: Eulophidae) based on molecular and morphological evidence

Ratzeburgiola Erdös is a small but phylogenetically interesting genus exhibiting a combination of characters once used to define both the former tribes Elachertini and Eulophini of the subfamily Eulophinae (Hymenoptera: Chalcidoidea: Eulophidae). It was once classified in the tribe Elachertini with genera having scutellar grooves and complete notauli, but in some characters it resembles the genus Pnigalio Schrank from the former tribe Eulophini. As part of a revision of Pnigalio we investigated the phylogenetic relationships between Ratzeburgiola and Pnigalio using both morphological and molecular data. Based on our results we synonymize Ratzeburgiola under Pnigalio n. syn., transfer its two included species to Pnigalio as P. cristatus (Ratzeburg) comb. n. and P. incompletus (Bouček) comb. n., and reassess the phylogenetic and taxonomic value of morphological characters traditionally considered important at the genus level.