The complex of two- and three-celled eucerine bees (Hymenoptera: Apoidea: Apidae: Eucerini), phylogenetic reconstruction and generic boundaries

Bees of the tribe Eucerini (Hymenoptera: Apoidea: Apidae) constitute an important guild of pollinators, with over 730 species worldwide, but basic faunistic and systematic knowledge on the group is rather poor. The study I propose to perform focuses on a complex of taxa, representing one of the few groups of bees with a highly unstable generic classification. Two Palaearctic genera, Eucera and Cubitalia, are distinguished from the remaining members of this complex by having two, rather than three, submarginal cells in their forewing. A recent revision of the entire tribe challenged the traditional classification of eucerines and synonymized some of the two- and three-celled taxa. However, overlapping morphological features among species in the complex make the determination of higher taxonomic levels within the tribe difficult. Furthermore, a morphology-based phylogeny of the group rendered the large genus Eucera as polyphyletic and another large genus, Tetraloniella, is predicted to be a paraphyletic taxon. In this study I propose to use molecular analysis to explore the phylogenetic relationships among the taxa of the eucerine complex. Using the phylogenetic evidence, I will establish a classification based on morphological characters of these taxa, thereby laying the foundation for a systematic revision of the higher taxa in the tribe Eucerini.