A50: Packer, L. 1998. A phylogenetic analysis of western European species of the Lasioglossum leucozonium species-group (Hymenoptera: Halictidae): sociobiological and taxonomic implications. Canadian Journal of Zoology. 76: 1611-1621.
Abstract: A data matrix of 81 characters for 23 species of the subgenus Lasioglossum sensu Michener (1999) is analysed cladistically with the primary purpose of obtaining a phylogeny for western European species of the Lasioglossum leucozonium group. Outgroup taxa were chosen on the basis of published species groupings for Old World species and a phylogeny for the New World species. Outgroup resolution was poor but results for the ingroup were consistent and indicate that (i) the social behaviour recorded for L. aegyptiellum is nested within a solitary background and therefore represents an origin of sociality independent of all others within the Halictidae, (ii) the monotypic subgenus Sericohalictus is a derived member of the leucozonium species-group, and (iii) L. laevigatum is not a member of this group.