Lasioglossum (Dialictus) albipenne (Robertson)

Gibbs, Jason, 2011, Revision of the metallic Lasioglossum (Dialictus) of eastern North America (Hymenoptera: Halictidae: Halictini), Zootaxa 3073, pp. 1-216 : 43-44

Lasioglossum (Dialictus) albipenne (Robertson)

Halictus albipennis Robertson, 1890: 317 . Ƥ 3.

Lectotype. Ƥ USA, Illinois, [Carlinville] (C. Robertson); [ANSP: 4251] designated herein. Examined. Halictus nubilis Lovell, 1905a: 40 . Ƥ.

Lectotype. Ƥ USA, Maine, Waldoboro, 2.viii. (J.H. Lovell); [NMNH: 71570] designated herein. Examined. Halictus (Chloralictus) lactineus Sandhouse, 1924: 34 . Ƥ.

Holotype. Ƥ USA, Colorado, Boulder, 4.viii.1908 (S.A. Rohwer); [ NMNH: 26435]. Examined. Halictus (Chloralictus) basilicus Sandhouse, 1924: 36 . 3.

Holotype. 3 USA, Connecticut, Colebrook, 1– 7.ix., (W.M. Wheeler); [ NMNH: 26439]. Examined.

Taxonomy. Robertson, 1902b: Chloralictus albipennis , p. 249 (key); Viereck, 1916: Halictus (Chloralictus) albipennis , p. 707 (key); Michener, 1951: Lasioglossum (Chloralictus) albipenne , p. 1111, L. (C.) basilicum , p. 1112, L. (C.) lactineum , p. 1114 (catalogue); Mitchell, 1960: Dialictus albipennis Ƥ3, p. 378, D. basilicus 3, 383 (redescription); Knerer and Atwood, 1966a: Dialictus basilicus Ƥ, p. 881 (description); Krombein, 1967: Lasioglossum (Dialictus) albipenne , p. 462, L. (D.) basilicum , p. 462 (catalogue); Hurd, 1979: Dialictus albipennis , p. 1963, D. basilicus , p. 1964, D. lactineus , p. 1967 (catalogue); Moure & Hurd, 1987: Dialictus albipennis , p. 88, D. basilicus , p. 92, D. lactineus , p. 109 (catalogue); Gibbs, 2010b: Lasioglossum (Dialictus) albipenne Ƥ3, p. 57 (redescription, key, synonymies).

Diagnosis. Female L. albipenne can be recognised by the following diagnostic combination: head and mesosoma bluish; wings white, pterostigma and venation pale yellow; hypostomal carinae parallel, unreflexed; mesoscutal punctures coarse, sparse between parapsidal lines (i=1–3d); mesepisternum coarsely reticulate-rugose; propodeum strongly carinate; T1 acarinarial fan large without dorsal opening; and metasomal terga brown with dense tomentum, distinctly punctures throughout. They are most similar to L. cressonii , L. disparile , and L. nymphaearum . Female L. cressonii have the head and mesosoma golden green, mesoscutal punctures relatively dense (i=1–1.5d) and wings faintly dusky. Female L. disparile have a distinct glabrate band on the declivitous surface of T1 separating the acarinarial fan from a dorsal hair band. Female L. nymphaearum have hypostomal carina reflexed distally and propodeal dorsal and posterior surfaces separated by uninterrupted transverse carina.

Male L. albipenne are similar to females except for the following: head elongate (length/width ratio = 0.99–1.08); face obscured by abundant white hairs; flagellomeres short (length/width ratio = 1.21–1.31), bright yellow ventrally; and mesepisternum punctate-reticulate. They are most similar to L. pruinosum and L. nymphaearum . Male L. pruinosum have the clypeus with distal yellow maculation. Male L. nymphaearum have tegula distinctly punctate.

Range. Nova Scotia west to British Columbia, south to North Carolina, Colorado and Oregon. USA: CO, CT, IL, IA, KS, MA, ME, MI, MN, ND, NE, NH, NJ, NY, SD, TN, VT, WI, WV. CANADA: AB, BC, MB, NB, NS, ON, PE, SK.

DNA Barcode. Available. Multiple sequences.

Comments. Common.

Variation in the strength of the female propodeal carinae can be seen in long series. Individuals with weaker carinae have been treated as separate species ( Knerer & Atwood 1966a).

The specimen of Halictus albipennis indicated above is designated herein as the lectotype to ensure future stability in the application of the name. Some of Robertson’s syntype series include more than one species, which could potentially lead to taxonomic confusion. An invalid lectotype led Gibbs (2010b) to treat the name Halictus nymphaearum as a junior subjective synonymy of L. albipenne (for discussion see Gibbs 2010b, below). Other subjective synonymies have also recently been made ( Gibbs 2010b). The specimen of Halictus nubilis indicated above is designated herein as the lectotype to ensure future stability in the application of the name.