Dual origins of social parasitism in North American Dialictus (Hymenoptera: Halictidae) confirmed using a phylogenetic approach

Abstract

The bee subgenus Dialictus (Halictidae: Lasioglossum) displays a large array of behaviours including solitary behaviour, eusociality, and social parasitism. Socially parasitic Dialictus share a suite of morphological traits; these could result from shared ancestry, but given their functional significance, could also have resulted from adaptive convergence. A combined morphological and molecular phylogenetic approach was used to test for monophyly of North American socially parasitic Dialictus. Two data sets were used in the phylogenetic analyses. First, short mitochondrial DNA sequences from previous taxonomic studies of North American Dialictus, including six social parasites, were used because of the broad taxon sampling they provide. These data were analysed in combination with a set of 40 morphological characters, including a large proportion of characters associated with social parasitism. Phylogenetic analysis of the combined DNA barcode and morphology data set resolves two distinct lineages of social parasite. The second data set was based on three genes (cytochrome c oxidase subunit 1, elongation factor 1α, and long‐wavelength rhodopsin), but with sparser taxon sampling, including one representative from each putative social parasite‐lineage. This also supported dual origins of social parasitism among North American Dialictus. The evolution of social parasitism is discussed. © The Willi Hennig Society 2011.

Origins, Evolution, and Diversification of Cleptoparasitic Lineages in Long-Tongued Bees

“…This observation, together with the pathway presented above, may help explain the conspicuous discrepancy concerning the appearance of cleptoparasitic lineages among bee families (Wcislo ). Our results, together with those of Cardinal et al (), indicate nine or 10 independent origins of cleptoparasitism in the bee families Megachilidae and Apidae; nine additional origins are posited in the subfamily Halictinae, although some of these origins may in fact represent social parasites and not cleptoparasites (Michener ; Gibbs et al ). Yet there are no confirmed cleptoparasitic lineages in the families Andrenidae, Colletidae, and Melittidae, nor in the halictid subfamilies Nomiinae and Rophitinae (although see Daly and Magnacca [] regarding purported cleptoparasitism in the colletid subgenus Hylaeus [ Nesoprosopis ]).…”

A new species, <i>Lasioglossum (Eickwortia) hienae</i>, from Mexico (Apoidea: Halictidae)

“…The carinate pronotum evident in these bees may also serve to protect the sensitive areas between the head and pronotum from biting (Pabalan et al, 2000). Similar modifications of the head and pronotum are evident in many halictid bees (Engel et al, 2012;Gibbs et al, 2012a).…”

Flexible Host Choice and Common Host Switches in the Evolution of Generalist and Specialist Cuckoo Bees (Anthophila: Sphecodes)

“…However, a pitfall of the ancestral host group reconstruction method arises because some identified hosts might not have yet existed when the ancestral Sphecodes species lived and diverged. According to Gibbs et al [58], [70], the most recent common ancestor of Sphecodes lived before approximately 25 MYA, and the divergence of host Lasioglossum lineages ( Lasioglossum s. s. and other subgenera of this genus) occurred before approximately 30 MYA. These results suggest that the Lasioglossum lineages had already diverged when the MRCA of Sphecodes arose.…”