Lasioglossum (Dialictus) packeri 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 : 230-234

Lasioglossum (Dialictus) packeri Gibbs , new species

( Figures 167A–D , 168A–F )

Holotype. ♀ CANADA, Saskatchewan, Grassland National Park , prairie, N49.0711 W106.52935, 830 m, 4.vi.2007 (Goulet, Boudreault & Fernandez); [ PCYU].

Diagnosis. Females of L. packeri can be recognised by the diagnostic combination of a small size (4.0– 4.4 mm), wide head (length/width ratio = 0.90–0.95), distinctly separated punctures on the frons (i=1–1.5d), very wide gena nearly 1.5 times wider than eye with widest point at midlength of eye ( Fig. 167D ), parallel hypostomal carinae, highly polished mesosoma due to lack of microsculpture, finely punctate mesepisternum distinct metatibial scopa, short basal rugae on metapostnotum that reach less than half way to posterior margin and brown metasoma with dense punctures on the dorsal surface of T1. They are similar to L. pallidellum and the southern USA species L. semibrunneum (Cockerell) (= Halictus oleosus Cockerell new synonymy). Female L. pallidellum have the gena narrower than the eye. Female L. semibrunneum have the gena narrower except some large specimens with a distinct tubercle located below the midlength of they eye and sparse punctures on the dorsal surface of T1.

Males of L. packeri can be recognised by the diagnostic combination of small size (3.4–4.1 mm), abundant facial tomentum, short flagellomeres (length/width ratio = 1.00–1.25) that are bright yellow ventrally, acute dorsolateral angle of the pronotum, distinct mesepisternal punctures and short rugae on the metapostnotum reaching only halfway to the posterior margin.

FEMALE. Length 3.97–4.39 mm; head length 1.27–1.44 mm; head width 1.34–1.61 mm; forewing length 3.05–3.23 mm.

Colouration. Head and mesosoma bluish green with golden reflections. Labrum reddish to orange-yellow. Mandible orange-yellow. Clypeus with apical half blackish brown. Antenna dark brown, F2–F10 with ventral surface orange-yellow. Tegula translucent amber. Wing membrane subhyaline, venation and pterostigma pale yellow. Legs brown, medio- and distitarsi reddish brown. Metasoma dark brown, terga and sterna with apical margins translucent brownish yellow.

Pubescence. Dull white to white. Moderately dense. 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 abundant tomentum. Propodeum with moderately dense plumose hairs on lateral and posterior surfaces (2–2.5 OD). Metasomal terga with abundant setae. T1 acarinarial fan complete dorsally. T1 basolaterally and T3–T5 entirely with sparse tomentum. T2 apicolateral and T3–T4 apical margins with sparse fringes.

Surface sculpture. Face polished, punctation fine, deep. Clypeal punctation sparse (i=1–6d). Supraclypeal area with punctation moderately sparse (i=1–3d). Lower paraocular area punctation dense (i=d). Antennocular area punctation moderately dense (i=1–1.5d). Upper paraocular area and frons punctation distinctly separated (i=1–1.5d). Ocellocular area minutely punctate (i=d). Gena polished. Postgena imbricate. Mesoscutum polished, punctation sparse between parapsidal lines (i=1–5d), closer laterad of parapsidal lines and on anterolateral portion of disc (i=1–1.5d). Mesoscutellum polished, virtually impunctate. Axilla punctate. Metanotum distinctly minutely punctate (i≤d). Preëpisternum obscurely punctate (i≤d). Hypoepimeral area and mesepisternum polished, distinctly and finely punctate (i=1–1.5d). Metepisternum with dorsal third weakly rugulose and ventral portion imbricate. Metapostnotum basal half weakly rugoso-striate, apical half polished. Propodeum with dorsolateral slope weakly imbricate, lateral and posterior surfaces tessellate. Metasomal terga coriarious, punctation very fine and obscure throughout (i=1–2d).

Structure. Head wide (length/width ratio = 0.90–0.95). Eyes weakly convergent below (UOD/LOD ratio = 1.06–1.08). Clypeus 2/3 below suborbital tangent, apicolateral margins very strongly convergent. Antennal sockets close (IAD/OAD> 0.6). Frontal line carinate, ending 1 OD below median ocellus. Gena at midlength approximately 1.5 times as wide as eye. Pronotum with dorsolateral angle orthogonal. Metatibial spur with 3 teeth. Metapostnotum moderately elongate (MMR ratio = 1.28–1.44), posterior margin rounded onto posterior surface. Propodeum with oblique carina absent, lateral carina weak, not reaching dorsal margin.

MALE. Similar to female except for the usual secondary sexual characters and as follows. Length 3.36– 4.09 mm; head length 1.08 mm; head width 1.14 mm; forewing length 2.26–2.50 mm.

Colouration. Labrum brownish yellow. Mandible yellow, apex red, base blackish brown. Flagellum with ventral surface yellow. Tibial bases and apices, and tarsi pale brownish yellow.

Pubescence. Face below ocelli with dense tomentum obscuring surface. Clypeus with moderately sparse tomentum partially obscuring surface. Gena with moderately dense tomentum partially obscuring surface. S2– S4 with dense plumose hairs (1.5–2 OD).

Surface sculpture. Clypeal punctation relatively dense (i=1–2d). Metasomal terga with distinct punctation throughout (i=1–2d).

Structure. Head wide (length/width ratio = 0.95). Eyes strongly convergent below (UOD/LOD ratio = 1.28). Clypeus 1/2 below suborbital tangent, apicolateral margins convergent. Antennal sockets distant (IAD/ OAD> 1.1). Frontal line carinate, ending 1.5 OD below median ocellus. Pedicel longer than or subequal to F1. F2 length 1.4–1.5X F1. F2–F10 short (length/width ratio = 1.00–1.25). Gena narrower than eye. Metapostnotum elongate (MMR ratio = 1.05–1.25), posterior margin broadly rounded onto posterior surface.

Terminalia . Genitalia as in Fig. 168D–F . Gonostylus small, dorsal setae elongate. Retrorse lobe narrow, strongly attenuated apically.

Range. Saskatchewan, Alberta south to Colorado ( Fig. 165 ).

Allotype. ♂ CANADA: SASKATCHEWAN: Grasslands N.P., N49.1799 W107.40047, 27.vii.1996 (A. T. Finnamore); [ PMAE].

Paratypes. CANADA: ALBERTA: 2♀ Cypress Co., 10 km S Manyberries, Hwy 501, N49.26131 W110.59052, 948 m, 13.vi.2007 (Gibbs & Sheffield); [ PCYU] ; 1♀ Writing-On-Stone P.P., Grass-north , 17– 26.iv.1990 (D. McCorquodale); [ PMAE] ; SASKATCHEWAN: 1♀ topotypical ; 1♀ 18 km S of Maple Creek , 3000ft., 16.vii.2005 (J. R. Vockeroth); [ PCYU] ; 1♀ Grasslands N.P., N49.1791 W107.40721, 2.vii.1996 (A. T. Finnamore) ; 1♀ Grasslands N.P., N49.179997 W107.40047, 2.vii.1996 (A. T. Finnamore) ; 1♀ Grasslands N.P., N49.1316 W107.59919, 13.vii.1996 (A. T. Finnamore) ; 1♀ Grasslands N.P., N49.1791 W107.40721, 14.vii.1996 (A. T. Finnamore) ; 1♀ Grasslands N.P., N49.17997 W107.40047, 14.vii.1996 (A. T. Finnamore) ; 1♀ Grasslands N.P., N49.1799 W107.40047, 23.vii.1996 (A. T. Finnamore) ; 1♀ Grasslands N.P., N49.1791 W107.40721, 23.vii.1996 (A. T. Finnamore) ; 2♀ Grasslands N.P., N49.1432 W107.44675, 23.vii.1996 (A. T. Finnamore) ; 1♀ Grasslands N.P., N49.1791 W107.40721, 27.vii.1996 (A. T. Finnamore) ; 2♀ Grasslands N.P., N49.1799 W107.40047, 27.vii.1996 (A. T. Finnamore) ; 1♀ Grasslands N.P., N49.1903 W107.37732, 28.vii.1996 (A. T. Finnamore); [ PMAE] ; MANITOBA: 1♀ Russell , 21.vii.1954 (Brooks & Wallis); [ CNC] ; USA: COLORADO: 1♀ ( H. oleosus homotype) Logan Co., Sterling , 18.vi.1923 (G. Sandhouse) ; 1♀ ( H. oleosus homotype) Logan Co., Sterling , 28.vi.1923 (G. Sandhouse); [ ANSP] ; 1♀ Logan Co., Sterling , 18.vi.1923 (G. Sandhouse); [ CNC] ; SOUTH DAKOTA: 1♀ Badlands National Park , 20.viii.2008 ; 3♀ 2♂♂ Badlands National Park , 4.ix.2008; [ BLNP] .

Etymology. It is a pleasure to name this species for Laurence Packer for his studies of Halictine sociobiology and in gratitude for supervising my doctoral research.

Comments. Uncommon.

Figures

FIGURE 165. Distribution of Lasioglossum oceanicum (light grey), L. pacatum (medium grey), and L. packeri (dark grey).

FIGURE 167. Lasioglossum packeri new species. Female (A) lateral habitus; (B) dorsal habitus; (C) face; (D) lateral view of head. Scale bars, A–C = 1 mm.

FIGURE 168. Lasioglossum packeri new species. Male (A) lateral habitus; (B) dorsal habitus; (C) face; (D) ventral view of genital capsule; (E) dorsal view of genital capsule; (F) apical view of genital capsule. Scale bars, A–C = 1 mm, F = 0.5 mm.