New and little-known Canadian Lasioglossum (Dialictus) (Hymenoptera: Halictidae) and an emended key to species

Abstract

A revised key to the 94 species of Lasioglossum (Dialictus) currently known to occur in Canada is presented, incorporating new species and taxonomic updates since the publication of the first key in 2010. Two new species, Lasioglossum (Dialictus) immigrans and Lasioglossum (Dialictus) onuferkoi, are described from Canada. Lasioglossum (D.) ascheri, L. (D.) stictaspis, and L. (D.) tegulariforme are reported or confirmed from Canada for the first time. Lasioglossum (D.) gaudiale (Sandhouse, 1924) and L. (D.) helianthi (Cockerell, 1916) are resurrected from synonymy with L. (D.) tegulariforme (Crawford, 1907). The following five new synonymies are established: L. (D.) stictaspis (Sandhouse, 1923) (= L. (D.) albuquerquense (Michener, 1937)); L. (D.) ascheri Gibbs, 2011 (= L. (D.) curculum Gibbs, 2011); L. (D.) helianthi (Cockerell, 1916) (= L. (D.) imbrex Gibbs, 2010); L. (D.) megastictum (Cockerell, 1937) (= L. (D.) punctiferellum (Cockerell, 1937)); and L. (D.) obnubilum (Sandhouse, 1924) (= L. (D.) lilliputense Gibbs, 2010). Previously undescribed males of L. (D.) helianthi, L. (D.) reasbeckae, L. (D.) tegulariforme, and L. (D.) weemsi are diagnosed and figured.

A checklist of the bees (Hymenoptera: Apoidea) of Manitoba, Canada

“…In some cases, "new" records are difficult to define because specimens may be recorded outside of the traditional scientific literature, either in theses (Patenaude 2007;Semmler 2015;Olynyk 2017) or within online databases. In addition, the collaborative nature of our research has meant that some bees first identified as part of this study, including new generic records for the province and new Canadian records, were released early to benefit other studies (Gardner and Gibbs 2021;Onuferko et al 2021;Satyshur et al 2021;Wrigley et al 2021) or were being worked on simultaneously as part of graduate theses (Hanuschuk 2021;Miller 2021;Martini 2022). Our goal is to provide accessible, verifiable data for interesting records, even if there may be an earlier record outside of peer-reviewed publications.…”

“…Relatively few of the studies on wild bees in Manitoba have resulted in peer-reviewed publications (but see Neave 1933;Turnock et al 2006;Semmler et al 2018;Robson et al 2019;Gibbs et al 2021;Olynyk et al 2021). In 2017, research on wild bees at the University of Manitoba, Winnipeg, began in earnest, the results of which included the discovery of many new provincial records (Semmler et al 2018;Gardner and Gibbs 2021;Onuferko et al 2021;Satyshur et al 2021;Wrigley et al 2021). Among these were new national records and new species, as well as erroneous published records based on misidentified material.…”

Revision of the Nearctic species of the Lasioglossum (Dialictus) gemmatum species complex (Hymenoptera: Halictidae)

“…Additionally, females have the propodeum with a distinct oblique carina, and males have the mesepisternum and often propodeum lateral face shiny with large, distinct punctures, and metasomal sterna with moderately sparse plumose pubescence 1-2 OD long. Some members of the L. perdifficile complex (defined in Gardner & Gibbs 2022) have a similar tegula, but these have more than 50% of the clypeus projecting below the suborbital tangent, females with propodeum oblique carina absent, and T1 with lateral tomentum. Some atypical specimens of L. knereri Gibbs, 2010 from California (possibly representing a cryptic species) also have a similar tegula, but have the propodeum without a distinct oblique carina, the metasomal terga all without appressed tomentum, and males have the metasomal sterna with very long and dense scopa-like pubescence (> 2 OD).…”

“…Lasioglossum imbrex was recorded from Alberta in Gibbs (2010), but all of the Alberta specimens were subsequently re-examined and determined as L. stictaspis in Gardner & Gibbs (2022). These specimens were not labelled as paratypes and it was not realised until after publication of Gardner & Gibbs (2022) that they were originally listed as such, and that the L. imbrex type series was mixed. ) helianthi (Cockerell, 1916) (black squares) and predicted distribution by maximum entropy ecological niche modelling in Maxent (colour shading).…”

“…This group is extremely widespread in the Western Hemisphere, ranging throughout most of North America (only absent from northern Canada) (Gardner & Gibbs 2022) and western South America from Colombia to Argentina and Chile (Engel 2000;unpublished data). It occurs even on remote islands including Hawaii (Tabor & Koch 2021), the Greater Antilles (Gibbs 2018b), Isla Socorro (unpublished data), and the Archipiélago de Juan Fernández (Engel 2000).…”