Lasioglossum (Dialictus) fattigi (Mitchell)

Gibbs, Jason, 2011, Revision of the metallic Lasioglossum (Dialictus) of eastern North America (Hymenoptera: Halictidae: Halictini), Zootaxa 3073, pp. 1-216 : 89

Lasioglossum (Dialictus) fattigi (Mitchell)

Dialictus fattigi Mitchell, 1960: 392 . Ƥ.

Holotype. Ƥ USA, Georgia, Neel Gap, 4.viii.1945 (P.W. Fattig); [ NCSU]. Examined.

Taxonomy. Krombein, 1967: Lasioglossum (Dialictus) fattigi , p. 463 (catalogue); Hurd, 1979: Dialictus fattigi , p. 1966 (catalogue); Moure & Hurd, 1987: Dialictus fattigi , p. 100 (catalogue); Gibbs, 2010b: Lasioglossum (Dialictus) fattigi Ƥ3, p. 129 (redescription, key).

Diagnosis. Female L. fattigi can be recognised by the following diagnostic combination: lower paraocular punctures relatively sparse (i=1–1.5d); mesoscutum weakly imbricate, punctures moderately dense between parapsidal lines (i=1– 2d); mesepisternum tessellate-imbricate, shallow punctures visible; T1 acarinarial fan with dorsal opening; T1 declivitous surface dull due to distinct coriarious microsculpture; and T3–T4 with sparse tomentum not obscuring surface and weak apical fringes. They are most similar to L. paradmirandum and L. katherineae . Female L. paradmirandum have head less robust, dense punctures on lower paraocular area (i≤d), mesoscutum tessellate, and T3–T4 with relatively dense tomentum partially obscuring surface and strong apical fringes. Female L. katherineae have T1 acarinarial fan complete, without dorsal opening.

Male L. fattigi are similar to females but may be further distinguished by head elongate (length/width ratio = 1.07); flagellomeres moderately elongate (length/width ratio = 1.62–1.64), pale brownish yellow ventrally; mesepisternum imbricate-tessellate; metapostnotum with posterior margin rounded onto vertical surface; and apical impressed areas of metasomal terga impunctate. They are most similar to L. mitchelli and L. paradmirandum . Male L. mitchelli have posterior margin of metapostnotum distinctly angled, mesoscutum more densely punctate, and mesepisternum rugulose. Male L. paradmirandum have head shorter (length/width ratio = 1.03–1.04) and upper portion of mesepisternum weakly reticulate.

Range. Ontario south to Georgia. USA: GA, MA, NC, NH, NY. CANADA: ON.

DNA Barcode. Available. Multiple sequences.

Comments. Lasioglossum fattigi is usually uncommonly collected, however, a long series was examined from the Niagara region of southern Ontario ( Richards et al. 2011).