Lasioglossum (Dialictus) ebmerellum 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 : 116-120

Lasioglossum (Dialictus) ebmerellum Gibbs , new species

( Figures 101A–D , 102A–F )

Holotype. ♀ CANADA, Alberta, 15 km N Elkwater, Hwy 41, N49.93857 W110.34962, 625 m, (Gibbs & Sheffield), on yellow composite [ PCYU: PYU-1603]

Diagnosis. Females of L. ebmerellum can be recognised by the diagnostic combination of an elongate face (length/width ratio = 1.04–1.06) with a strongly protruding clypeus, moderately dense mesoscutal punctures (i=1–1.5d), subhyaline wings, distinct punctures on the mesoscutum, metapostnotum with rugae reaching approximately 2/3 of the distance to apical margin ( Fig. 101D ); brown metasomal terga with dense tomentum on T3–T4 and T1 acarinarial fan very dense. They are most similar to L. hyalinum which have a round head (length/width ratio = 0.94–0.95) and hyaline wings.

Males of L. ebmerellum can be recognised by the diagnostic combination of a weakly convergent eyes (UOD/LOD ratio = 1.16), elongate mandibles, gena width subequal to eye, distinct mesepisternal punctures, coarsely punctate dorsolateral slope of the propodeum and strong punctures throughout on the metasomal terga.

Description. FEMALE. Length 5.49–6.40 mm; head length 1.80–1.94 mm; head width 1.73–1.85 mm; forewing length 4.58–4.64 mm.

Colouration. Head and mesosoma blue with greenish reflections to green with golden reflections. Clypeus with apical half blackish brown, basal half, and supraclypeal area bronze. Antenna dark brown, F2–F10 with ventral surface orange-yellow. Tegula dark amber. Wing membrane hyaline, venation and pterostigma pale honey-coloured. Legs brown, tibial bases, medio- and distitarsi reddish brown. Metasoma dark brown, terga and sterna with apical margins reddish to pale yellow.

Pubescence. Dull white. Moderately abundant. Head and mesosoma with dense woolly hairs (1–1.5 OD), longest on genal beard, metanotum and mesopleuron (2–2.5 OD). Lower paraocular area with very sparse subappressed tomentum. Gena with tomentum. Propodeum with dense plumose hairs on lateral and posterior surfaces (2–2.5 OD). Metasomal terga with moderately dense, fine setae. T1 acarinarial fan dense, complete dorsally. T1 dorsolateral portion, T2 basolaterally and T3–T5 entirely with dense tomentum. T2 apicolateral and T3–T4 apical margins with sparse fringes.

Surface sculpture. Face imbricate, punctation moderately strong. Clypeal punctation moderately sparse (i=1.5–2d), apical half nearly impunctate. Supraclypeal area with punctation moderately sparse (i=1–2d). Lower paraocular and antennocular areas with punctation dense (i≤d). Upper paraocular area and frons punctate-reticulate. Ocellocular area minutely punctate (i≤d). Gena and inner half of postgena strigate, outer half polished. Mesoscutum polished, weakly imbricate anteromedially, punctation fine, moderately dense between parapsidal lines (i=1–1.5d), dense laterad of parapsidal lines and on anterolateral portion of disc (i<d). Mesoscutellum similar to mesoscutum, submedial punctation sparse (i=1–3d). Axilla densely punctate. Metanotum imbricate-punctate. Preëpisternum reticulate. Hypoepimeral area reticulate-punctate. Mesepisternum polished, coarsely punctate above, very finely punctate below. Metepisternum dorsal third rugulose-striate, ventral portion imbricate. Metapostnotum rugoso-striate, reaching approximately two-thirds of the distance to posterior margin, posterior margin smooth, weakly imbricate. Propodeum with dorsolateral slope rugulose on anterior half, imbricate on posterior half, lateral surface minutely reticulate to tessellate, posterior surface strongly imbricate. Metasomal terga weakly coriarious, punctation on basal halves dense (i=1–1.5d), sparse on apical halves (i=2–2.5d).

Structure. Head elongate (length/width ratio = 1.04–1.06). Eyes weakly convergent below (UOD/LOD ratio = 1.05–1.07). Clypeus 9/10 below suborbital tangent, apicolateral margins convergent. Antennal sockets close (IAD/OAD <0.5). Medial ocellus below upper ocular tangent. Gena narrower than eye. Inner metatibial spur pectinate with 4 teeth. Metapostnotum moderately elongate (MMR ratio = 1.19–1.23), posterior margin weakly angled onto posterior surface. Propodeum with oblique carina very weak or absent, lateral carina not reaching dorsal margin.

MALE. Similar to female except for the usual secondary sexual characters and as follows. Length 6.15 mm; head length 1.84 mm; head width 1.81 mm; forewing length 4.51 mm.

Colouration. Head and mesosoma blue. F1–F11 with ventral surface yellow. Tegula reddish brown. Metasoma blackish brown, terga and sterna with apical margins reddish.

Pubescence. Clypeus, and supraclypeal area with sparse tomentum. Lower paraocular area with very dense pubescence, completely obscuring surface below. Paraocular area and frons below level of eye emargination with dense tomentum largely obscuring surface. Gena with sparse tomentum. Metasomal terga lateral portions with moderately dense pubescence. Metasomal sterna with sparse pubescence.

Surface sculpture. Gena closely punctate-lineolate (i<d). Mesepisternum polished, coarsely punctate (i=d). Propodeum with dorsolateral slope and posterior surface punctate (i≤d), lateral surface reticulate-punctate. Metasomal terga deeply punctate (i=1–2d), T4–T6 apical impressed areas impunctate.

Structure. Head moderately elongate (length/width ratio = 1.01). Eyes weakly convergent below (UOD / LOD ratio = 1.16). Mandible moderately elongate, nearly reaching opposing mandible base. Clypeus 4/5 below suborbital line, anterolateral margins convergent. Antennal sockets distant (IAD/OAD = 1.5). Frontal line carinate, ending 2 OD below median ocellus. Pedicel shorter than F1. F2 length 1.5X F1. F2–F10 (length/ width ratio = 1.43–1.57). Metapostnotum moderately elongate (MMR ratio = 1.31), posterior margin rounded onto posterior surface.

Terminalia . S7 with median lobe strongly clavate, apex rounded ( Fig. 102F ). S8 with apicomedial margin weakly convex ( Fig. 102F ). Genitalia as in Fig. 102D–E . Gonobase with ventral arms narrowly separated. Gonostylus small, dorsal setae elongate. Retrorse lobes narrow, attenuated and reflexed apically.

Range. Alberta, south to Nevada, Utah ( Fig. 103 ).

Allotype. NEVADA: 1♂ Clark Co., 0.53 mi SSW Edna Grey Spr., 11S N4019493 E618228, 9037 ft, 28.vi.2004 (D. Skandilis); [ BBSL].

Paratypes. CANADA: ALBERTA: 1♀ Writing-On-Stone P.P., Sand-North , 18–25.vii.1990 (D. McCorquodale) ; 1♀ Writing-On-Stone P.P., Grass-South , 8.viii.1990 (M. Klassen) ; 1♀ Writing-On-Stone P.P., P. T . Sand W., 16–24.viii.1990 (D. McCorquodale); [ PMAE] ; USA: IDAHO: 1♀ Blaine Co., Ketchum, Sawtooth Botanic Gardens , 1726 m, 24.vi.2007 (Gibbs & Sheffield); [ PCYU] ; UTAH: 1♀ Washington Co. , 0.63 mi NNW Lemmon Spr., 12S N4129346 E33[0?]774, 2.vi.2006 (B. Hays & F. Nicklen) ; 1♀ Washington Co. , 0.75 mi WSW Stave Spr., 12S N4125316 E329919, 9.vi.2006 (B. Hays & F. Nicklen) ; 1♀ Washington Co. , 0.8 mi WSW Stave Spr., 12S N4125286 E329879, 19.vi.2006 (B. Hays & F. Nicklen) ; 1♀ Washington Co. , 0.8 mi WSW Stave Spr., 12S N4125286 E329879, 24.v.2006 (B. Hays & F. Nicklen); [ BBSL] .

Etymology. The specific epithet is a dedication to Andreas W. Ebmer in recognition of his studies of Lasioglossum s.l. and other halictid bees.

Floral records. ASTERACEAE : Hymenoxys lemmonii .

Figures

FIGURE 101. Lasioglossum ebmerellum new species. Female (A) lateral habitus; (B) dorsal habitus; (C) face; (D) metapostnotum. Scale bars, A–C = 1 mm.

FIGURE 102. Lasioglossum ebmerellum new species. 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.

FIGURE 103. Distribution of Lasioglossum ebmerellum (dark grey) and L. ellisiae (light grey).