Lasioglossum (Dialictus) fattigi (Mitchell)

Gibbs, Jason, 2010, Revision of the metallic species of Lasioglossum (Dialictus) in Canada (Hymenoptera, Halictidae, Halictini) 2591, Zootaxa 2591 (1), pp. 1-382 : 129-132

Lasioglossum (Dialictus) fattigi (Mitchell)

( Figures 109A–E , 110A–F )

Dialictus fattigi Mitchell, 1960: 392 . ♀. Holotype. ♀ 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).

Diagnosis. Most similar to L. paradmirandum . See the diagnosis for that species. Also similar to the Eastern USA species L. apocyni (Mitchell) which is distinguished by its distinctly flattened clypeus, narrow and elongate mandibles, and gena wider than eye.

Description. FEMALE. Length 4.03–5.55 mm; head length 1.25–1.54 mm; head width 1.27–1.54 mm; forewing length 3.23–3.90 mm.

Colouration. Head and mesosoma pale golden green, sometimes bluish. Clypeus with apical half blackish brown, basal half and supraclypeal area sometimes golden. Antenna dark brown, flagellum with ventral surface dark reddish brown. Tegula pale reddish brown. Wing membrane subhyaline, venation and pterostigma brownish yellow. Legs brown, medio- and distitarsi reddish brown. Metasoma brown, terga and sterna with apical margins translucent brownish yellow.

Pubescence. Dull white. Moderately sparse. Head and mesosoma with moderately dense woolly hairs (1– 1.5 OD), longest on genal beard, metanotum and mesopleuron (2–2.5 OD). Lower paraocular area and gena with virtually no tomentum. Propodeum with moderately dense plumose hairs on lateral and posterior surfaces (2–2.5 OD). Metasomal terga with sparse, fine setae. T1 acarinarial fan with wide dorsal opening, equal to width of lateral hair patches. T2 basolaterally and T3–T5 entirely with sparse tomentum not greatly obscuring surface. T2 apicolateral and T3–T4 apical margins with weak fringes.

Surface sculpture. Face weakly imbricate, punctation moderately strong. Clypeus polished, punctation sparse (i=1–3d). Supraclypeal area with punctation sparse (i=1–3d). Lower paraocular and antennocular areas with punctation moderately dense (i=1–1.5d). Upper paraocular area and frons reticulate-punctate. Ocellocular area minutely punctate (i=1–1.5d). Gena weakly lineolate. Postgena polished, weakly imbricate. Mesoscutum weakly tessellate-imbricate, punctation fine, moderately sparse between parapsidal lines (i=1–2.5d), dense laterad of parapsidal line (i≤d), and reticulate on anterolateral portions. Mesoscutellum similar to mesoscutum, submedial punctation sparse (i=1–4d). Axilla punctate. Metanotum imbricate. Preëpisternum weakly rugulose. Hypoepimeral area imbricate. Mesepisternum weakly tessellate-imbricate with obscure shallow punctures (i=1.5–2d). Metepisternum dorsal third rugoso-striate, ventral portion imbricate. Metapostnotum weakly rugoso-striate, posterior margin imbricate. Propodeum with dorsolateral slope imbricate, lateral and posterior surfaces tessellate. Metasomal terga coriarious, punctation on basal halves moderately dense (i=1–1.5d), obscure on apical halves (i=2–2.5d), T1 dorsal portion and T2 apical half virtually impunctate.

Structure. Head round (length/width ratio = 0.98–1.00). Eyes convergent below (UOD/LOD ratio = 1.20– 1.21). Clypeus ½ below suborbital tangent, apicolateral margins strongly convergent. Antennal sockets moderately close (IAD/OAD <0.6). Frontal line carinate, ending 2.5 OD below median ocellus. IOD subequal to OOD. Gena narrower than eye. Inner metatibial spur pectinate with 3 teeth. Metapostnotum moderately elongate (MMR ratio = 1.33–1.40), posterior margin rounded onto posterior surface. Propodeum with oblique carina virtually absent, lateral carina weak, reaching halfway to dorsal margin.

MALE. Similar to female except for the usual secondary sexual characters and as follows. Length. 5.12 mm; head length. 1.44 mm; head width. 1.34 mm; forewing length. 3.48 mm.

Colouration. Flagellomeres with ventral surface orange-yellow. Tarsi brownish yellow.

Pubescence. Lower paraocular area with moderately dense tomentum obscuring surface. Gena without evident tomentum. S3–S5 with apical patches of appressed hairs.

Surface sculpture. Clypeal punctation moderately dense (i=1–1.5d). Metanotum rugose. Preëpisternum and hypoepimeral area rugulose. Metapostnotum with moderately strong rugae nearly reaching posterior margin. Propodeum with dorsolateral slope rugose, lateral and posterior surfaces ruguloso-imbricate. Metasomal terga polished, punctation moderately dense (i=1–2d) nearly reaching premarginal line, apical impressed areas impunctate.

Structure. Head elongate (length/width ratio = 1.07). Eyes strongly convergent below (UOD/LOD ratio = 1.52). Antennal sockets distant (IAD/OAD> 1.2). Frontal line carinate, ending 2 OD below median ocellus. Pedicel shorter than F1. F2 length 1.9X F1. F2–F10 moderately elongate(length/width ratio = 1.62–1.64). Propodeum dorsal surface moderately elongate (MMR ratio = 1.30), posterior margin weakly angled onto posterior surface.

Terminalia . S7 with median columnar, apex rounded ( Fig. 110F ). S8 with apicomedial margin weakly convex. Genitalia as in Fig. 110D–E . Gonobase with ventral arms widely separated. Gonostylus small, dorsal setae elongate. Retrorse lobes narrow, strongly attenuated apically.

Range. Ontario south to Georgia ( Fig. 108 ).

Additional material examined. CANADA: ONTARIO: 10♀ Brock University , residences, 31.vii.2003 ; 18♀ Glenridge , escarpment, 25.iv.2003 ; 3♀ Glenridge , escarpment, 28.v.2003 ; 1♂ Glenridge , escarpment, 26.ix.2003 ; 1♀ York University, Keele Campus, CSEB green roof, 20.vi.2005 (E. Willis); 1♀ York University, Keele Campus, Pond Rd. green roof, 17.viii.2006 (E. Willis) ; 1♀ Toronto, York University , N43.77175 W079.4965, 3.x.2006 (H. Ngo); [ PCYU] ; USA: GEORGIA: 1♀ Robin Bald , 9.viii.1957 (W. R. Richards); [ CNC] ; NORTH CAROLINA: 1♀ paratype McDowell Co., Parkway , 23.vi.1954 ( T. B. Mitchell); [ NMNH] .

Floral records. HYDRANGEACEAE : Hydrangea , RHAMNACEAE : Ceanothus , ROSACEAE : Aruncus .

Comments. Uncommon. First description of male.

Figures

FIGURE 108. Distribution of Lasioglossum ephialtum (light grey) and L. fattigi (dark grey).

FIGURE 109. Lasioglossum fattigi (Mitchell). Female (A) lateral habitus; (B) dorsal habitus; (C) face; (D) mesepisternum; (E) T3–T5. Scale bars, A–C = 1 mm.

FIGURE 110. Lasioglossum fattigi (Mitchell). Male (A) lateral habitus; (B) dorsal habitus; (C) face; (D) ventral view of genital capsule; (E) dorsal view of genital capsule; (F) S7, S8. Scale bars, A–C = 1 mm, F = 0.5 mm.