Lasioglossum (Dialictus) reasbeckae Gibbs, 2010

Gibbs, Jason, 2010, Revision of the metallic species of Lasioglossum (Dialictus) in Canada (Hymenoptera, Halictidae, Halictini) 2591, Zootaxa 2591 (1), pp. 1-382 : 276-279

Lasioglossum (Dialictus) reasbeckae Gibbs , new species

( Figure 193A–C )

Holotype. ♀ CANADA, British Columbia, Stoltz Meadows , 15 km E Lake Cowichan, N48°46´54´´ W123°3´06.9´´, 23.vii.2005 (E. Elle); [ PCYU].

Diagnosis. Females of L. reasbeckae can be recognised by the diagnostic combination of a golden green head and mesosoma, wide head (length/width ratio = 0.94–0.95), distinctly purplish supraclypeal area, smooth and shining integument with coarse moderately sparse punctures (i=1–2.5d) on the mesoscutum and mesepisternum, metapostnotum posterior margin smooth and shining, and dense, deep punctures on the brown metasomal terga, obscure on the apical impressed areas, T1 with impunctate posteromedial area wider than punctate posterolateral portion. They are most similar to L. abundipunctum , L. dashwoodi and L. punctatoventre . Female L. dashwoodi have clear metallic reflections on the metasomal terga. Female L. abundipunctum have distinct punctures on apical impressed areas of the metasomal terga. Female L. punctatoventre have metapostnotum posterior margin rough and dull, and T1 with impunctate posteromedial area narrower than punctate posterolateral portion.

Male unknown.

Description. FEMALE. Length 6.16–6.53 mm; head length 1.70–1.75 mm; head width 1.80–1.87 mm; forewing length 4.70–4.82 mm.

Colouration. Head and mesosoma golden green with some bluish reflections. Clypeus with apical 4/5 blackish brown, basal 1/5 brassy. Supraclypeal area purplish-brassy. Antenna dark brown, with ventral surface brownish yellow. Tegula dark, reddish brown. Wing membrane subhyaline, venation and pterostigma reddish brown. Legs brown, medio- and distitarsi brownish red. Metasomal terga weakly metallic golden green, sterna brown, apical margins reddish brown to translucent yellow.

Pubescence. Dull white. Moderately dense. Head and mesosoma with moderately sparse woolly hairs (1– 1.5 OD), longest on genal beard, metanotum and mesopleuron (2–2.5 OD). Lower paraocular area and gena with sparse tomentum not obscuring surface. Metanotum anteromedial portion with dense tomentum obscuring surface. Propodeum with moderately dense plumose hairs on lateral and posterior surfaces (2–2.5 OD). Metasomal terga with moderately dense, fine setae. T1 acarinarial fan sparse, complete dorsally, intermingled with erect hairs. T2 basolateral and T3–T4 with moderately dense tomentum, partially obscuring surface. T2 apicolateral and T3–T4 apical margins with weak fringes.

Surface sculpture. Face polished, weakly imbricate, punctation coarse. Clypeus with apical half weakly lineolate, punctation moderately sparse (i=1–2.5d). Supraclypeal area with punctation sparse (i=1–3d). Lower paraocular and antennocular areas with punctation dense (i≤d). Upper paraocular area and frons punctatereticulate. Ocellocular area irregularly punctate (i=1–2d). Gena shining, weakly striate. Postgena polished, coarsely punctate. Mesoscutum polished, anteromedial portion weakly imbricate, punctation coarse, sparse between parapsidal lines (i=1–2.5d), moderately dense laterad of parapsidal lines (i=1–1.5d), contiguous on anterolateral portions. Mesoscutellum similar to mesoscutum, submedial punctation sparse (i=2–4d). Axilla punctate. Metanotum ruguloso-imbricate. Preëpisternum reticulate-rugose. Hypoepimeral area polished, punctate (i=1–1.5d). Mesepisternum polished, weakly lineolate, coarsely punctate (i=1–1.5d). Metepisternum with dorsal third finely ruguloso-striate, ventral portion reticulate-imbricate. Metapostnotum anastomosingly rugose, posterior margin smooth. Propodeum with dorsolateral slope and lateral and posterior surfaces ruguloso-imbricate. Metasomal terga polished except apical margins coriarious, punctation on basal halves dense (i=1–2d), obscure on apical halves (i=2–3d).

Structure. Head wide (length/width ratio = 0.94–0.95). Eyes weakly convergent below (UOD/LOD ratio = 1.12–1.18). Clypeus 1/2–2/3 below suborbital tangent, apicolateral margins convergent. Antennal sockets close (IAD/OAD <0.5). Frontal line carinate, ending 2.5 OD below median ocellus. Gena narrower than eye. Inner metatibial spur pectinate with 4 teeth. Metapostnotum moderately elongate (MMR ratio = 1.13–1.21), posterior margin rounded onto posterior surface. Propodeum with oblique carina weak, obscure, lateral carina widely divergent, not reaching margin of dorsal surface.

MALE. Unknown.

Range. British Columbia ( Fig. 194 ).

Paratypes. CANADA: BRITISH COLUMBIA: 1♀ topotypical, 13.vii.2005 (E. Elle) ; 1♀ Cowichan Lake Forestry Stn., Ministry of Forests, Meachie Lk. , N48°49´07.9´´ W124°08´05.1´´, 13.vii.2005 (E. Elle); [ PCYU] ; 1♀ Vernon, Goose Lake , 10.v.1980 ( R. A. Cannings) ; 1♀ White Lake, Okanagan Falls , 30.vi.1990 ( R. A. Cannings & H. Nadel); [ RBCM] ; USA: OREGON: 1♀ Hood River Co., 11 mi S Mt. Hood , at powder spring, 4000 ft., 7.vii.1978 (N.L. Herman); [ AMNH] .

Etymology. The specific epithet is a dedication to my mother Connie Barbara Gibbs (née Reasbeck).

Comments. Uncommon.

Figures

FIGURE 193. Lasioglossum reasbeckae new species. Female (A) lateral habitus; (B) dorsal habitus; (C) face. Scale bars, A–C = 1 mm.

FIGURE 194. Distribution of Lasioglossum reasbeckae (dark grey) and L. ruidosense (light grey).