Juxtocellar Structures in Euglossine Bees: A New Character for Corbiculate Studies

Abstract

A new morphological structure is described and figured for orchid bees (Apinae: Euglossini). These minute features are located posterolateral to the ocelli and are termed "juxtocellar structures". The diversity of their form across Euglossini is described. Homologous structures were found in some related lineages of apid bees {e.g., Anthophorini, Centridini, Eucerini) while in others the structures were absent {e.g., Xylocopinae, Nomadinae). Most notably juxtocellar structures are apomorphically lost in all other corbiculate apine tribes {i.e., Bombini, Meliponini, Apini, Electrobombini, Electrapini, and Melikertini), a pattern which is in accordance with current phylogenetic hypotheses for the clade.