Lasioglossum (Dialictus) nigroviride (Graenicher)

Gibbs, Jason, 2011, Revision of the metallic Lasioglossum (Dialictus) of eastern North America (Hymenoptera: Halictidae: Halictini), Zootaxa 3073, pp. 1-216 : 148-149

Lasioglossum (Dialictus) nigroviride (Graenicher)

Halictus nigro-viridis Graenicher, 1910: 233. Ƥ.

Holotype. Ƥ USA, Wisconsin, Swiss, Burnett Co., 27.vii.1909, [Milwaukee: 32837]. Halictus (Chloralictus) richardsoni Cockerell, 1937: 113 . Ƥ.

Holotype. Ƥ Canada, Alberta, Wabamun , 60 miles E of Edmonton, 1.vii.1935 (E.H. Strickland); [ CNC: 4169]. Examined Evylaeus pineolensis Mitchell, 1960: 358 . 3. [new synonymy]

Holotype. 3 USA, North Carolina, Pineola , 3.viii.1937 (D.L. Wray); [ NMNH: 100875]. Examined.. Dialictus nigroviridis Knerer and Atwood, 1962b: 169 (Emend.)

Taxonomy. Cockerell, 1937: Halictus (Chloralictus) nigroviridis , p. 113 (diagnosis); Michener, 1951: Lasioglossum (Chloralictus) nigro-viride, p. 1115, L. (C.) richardsoni , p. 1117 (catalogue); Mitchell, 1960: Dialictus nigro-viridis Ƥ3, p. 406 (redescription); Krombein, 1967: Lasioglossum (Dialictus) nigroviride , p. 464 (catalogue); Hurd, 1979: Dialictus nigroviridis , p. 1968, D. richardsoni , p. 1971 (catalogue); Moure & Hurd, 1987: Dialictus nigroviridis , p. 115, D. richardsoni , p. 127 (catalogue); Gibbs, 2010b: Lasioglossum (Dialictus) nigroviride Ƥ3, p. 203 (redescription, key, synonymy).

Diagnosis. Female L. nigroviride can be recognised by the following diagnostic combination: size large (7.0– 8.1 mm); head and mesosoma golden; gena wider than eye; mesoscutal punctures sparse between parapsidal lines (i=1–4d), sometimes sparse laterad of parapsidal line (i=1–2d); mesepisternal punctures distinct, sparse (i=1–2.5d) ( Fig. 24 A); lateral carina reaching or nearly reaching oblique carina ( Fig. 2 B); and metasomal terga black-brown, tomentum and apical fringes. They are superficially similar to L. obscurum , which is smaller (4.9–5.9 mm) with weak propodeal carinae, and sparse apical fringe hairs on metasomal terga.

Male L. nigroviride can be recognised by the following diagnostic combination: size large (7.0– 7.5 mm); head and mesosoma golden green; flagellomeres elongate (length/width ratio = 1.60–1.87); mesoscutum polished due to weak microsculpture, punctures sparse between parapsidal lines (i=1–4d); mesepisternal punctures distinct; metasomal terga blackish brown; and S3 and apicolateral portions of S4 with very dense plumose hairs. Male L. obscurum are similar but have relatively sparse hairs on the metasomal sterna.

Range. Nova Scotia west to British Columbia, south to Georgia. USA: GA, MA, MD, ME, NC, NH, NY, PA, VT, WA, WI, WV. CANADA: AB, BC, MB, NS, ON.

DNA Barcode. Available. Multiple sequences.

Comments. Common.

Figures

FIGURE 2. Propodeum and metapostnotum variation in female Lasioglossum (Dialictus). (A) L. cressonii, (B) L. nigroviride, (C) L. lineatulum, (D) L. coreopsis, (E) L. connexum, (F) L. (D.) sp.

FIGURE 24. Mesepisternum (A) punctate, (B) impunctate (rugulose). (From Gibbs 2010 b).