Ellis, 1913 : 205 Revision of the metallic Lasioglossum (Dialictus) of eastern North America (Hymenoptera: Halictidae: Halictini) Gibbs, Jason Zootaxa 2011 2011-10-28 3073 1 216 3SF64 Ellis Ellis [151,702,390,416] Insecta Halictidae Lasioglossum Animalia Hymenoptera 184 185 Arthropoda species succinipenne Dialictus     Halictus succinipennis  Ellis, 1913: 205. Ƥ.    Holotype.Ƥ USA, Colorado, Florissant, 14.vi.1948on sand (S.A. Rohwer); [ NMNH: 28200]. Examined.  Taxonomy. Michener, 1951:  Lasioglossum( Chloralictus) succinipenne, p. 1118 (catalogue); Hurd, 1979:  Dialictus succinipennis, p. 1972 (catalogue);  Dialictus succinipennis, p. 1972 (catalogue); Moure & Hurd, 1987:  Dialictus succinipennis, p. 132 (catalogue); Gibbs, 2010b:  Lasioglossum( Dialictus) succinipenneƤ3, p. 317 (redescription, key).   Diagnosis.Female  L. succinipennecan be recognised by the following diagnostic combination: head long (length/ width ratio = 1.05–1.09), clypeus apicolateral margins weakly convergent, supraclypeal area elongate, mesoscutal punctures dense throughout (i<d), metapostnotum rugoso-carinulate, and metasomal terga metallic, with dense, whitish tomentum. They are most similar to  L. pilosumand  L. leucocomum. Female  L. pilosumhave subparallel apicolateral margins of clypeus and distinctly yellowish pubescence. Female  L. leucocomumhave a shorter supraclypeal area.  Male  L. succinipennecan be recognised by the following combination: head long (length/width ratio = 1.09–1.21), eyes strongly convergent below (UOD/LOD ratio = 1.38–1.48), clypeus yellow distally, mesoscutal punctures dense, mesepisternum with obscure punctures, metapostnotum rugoso-carinulate, metasomal terga metallic with dense and distinct punctures. They are most similar to  L. pilosum, which lacks mesepisternal punctures.  Range.Alberta and Manitoba south to Colorado, west to Illinois and southern Ontario.  USA: CO, IL, MN, NE, WI.  CANADA: AB, MB, ON.  DNA Barcode.Available. Multiple sequences.   Comments.Common in Midwest. Until recently,  L. succinipennewas only known from Colorado. It was later identified from Manitoba ( Patenaude 2007) and subsequently from numerous Midwestern sites (Wolf & Ascher 2009; Gibbs 2010b).