Lasioglossum (Dialictus) nevadense (Crawford)

Gibbs, Jason, 2010, Revision of the metallic species of Lasioglossum (Dialictus) in Canada (Hymenoptera, Halictidae, Halictini) 2591, Zootaxa 2591 (1), pp. 1-382 : 198-203

Lasioglossum (Dialictus) nevadense (Crawford)

( Figures 148A–C , 149A–F )

Halictus nevadensis Crawford, 1907: 195 . ♀.

Holotype. ♀ USA, Nevada, Ormsby Co., July (Baker); [ NMNH: 12074]. Examined.

Halictus (Chloralictus) pasadenae Michener, 1936: 285 . ♀.

Holotype. ♀ USA, California, Pasadena , 14.iii.1934, (C.D. Michener); [ CAS: 4616]. Examined.

Taxonomy. Michener, 1951: Lasioglossum (Chloralictus) nevadense , p. 1115 (catalogue); Krombein, 1958: Lasioglossum (Chloralictus) nevadense , p. 230, (catalogue); Hurd, 1979: Dialictus nevadensis , p. 1968 (catalogue); Moure & Hurd, 1987: Dialictus nevadensis , p. 114 (catalogue).

Diagnosis. Females of L. nevadense can be recognised by the diagnostic combination of a small size (4.1– 4.7 mm), round head (length/width ratio = 0.96–0.97), nearly entirely brown clypeus, brassy supraclypeal area, imbricate mesoscutum with moderately dense punctures on central disc (i=1–1.5d), dense mesepisternal punctures, rugae on metapostnotum not reaching posterior margin, propodeum with weak carinae, and metasoma brown with sparse tomentum and obscure punctures. They are most similar to L. incompletum which has strong oblique carinae on the propodeum.

Males of L. nevadense can be recognised by their small size (4.0– 4.2 mm), round head (length/width ratio = 0.95–0.96), face with dense tomentum limited to lower paraocular area, flagellomeres moderately short (length/width ratio = 1.33–1.60), polished mesoscutum due to weak microsculpture with fine moderately sparse punctures on central disc (i=1–2d), distinct mesepisternal punctures, brown metasomal terga with impunctate apical impressed areas and moderately dense hairs on the metasomal sterna. They are most similar to L. knereri and L. subversans which both have elongate, scopa-like hairs on the metasomal sterna.

Redescription. FEMALE. Length 4.09–4.70 mm; head length 1.18–1.39 mm; head width 1.22–1.44 mm; forewing length 2.99–3.54 mm.

Colouration. Head and mesosoma metallic green to deep blue. Clypeus with apical 4/5 blackish brown and basal portion, and supraclypeal area bronze. Antenna dark brown, flagellum with ventral surface reddishbrown to brownish yellow at apex. Tegula reddish brown. Wing membrane subhyaline, venation and pterostigma amber. Legs brown, medio- and distitarsi reddish brown. Metasoma dark brown, terga and sterna with apical margins reddish brown to 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 (1.5–2 OD). Sparse subappressed hairs on lower paraocular area and gena, not obscuring surface. Pronotum dorsolateral angle and lobe with dense tomentum. Propodeum with moderately dense plumose hairs on lateral and posterior surfaces (1.5–2 OD). Metasomal terga with moderately dense, fine setae. T1 acarinarial fan incomplete dorsally. T2–T3 basolaterally and T4 entirely with sparse tomentum, partially obscuring surface. T2 apicolateral and T3–T4 apical margins with sparse fringes.

Surface sculpture. Face imbricate, punctation fine. Clypeus with apical polished, punctation moderately sparse (i=1–3d). Supraclypeal area with punctation moderately sparse (i=1–3d). Lower paraocular and antennocular areas with punctation dense (i≤d). Upper paraocular area, frons and ocellocular area punctate-reticulate. Gena and postgena polished. Mesoscutum imbricate, punctation fine, dense between parapsidal lines (i≤d) except moderately dense on submedial portion (i=1–1.5d), dense laterad of parapsidal lines and on anterolateral portions (i<d). Mesoscutellum polished, submedial punctation sparse (i=2–4d). Axilla punctate. Metanotum imbricate. Preëpisternum ruguloso-imbricate. Hypoepimeral area weakly ruguloso-punctate. Mesepisternum dorsal portion weakly rugulose, ventral portion imbricate, punctation distinct (i≤d). Metepisternum with dorsal third striate, ventral portion imbricate. Metapostnotum longitudinally rugoso-striate. Propodeum with dorsolateral slope imbricate, lateral and posterior surfaces tessellate. Metasomal terga polished, weakly coriarious, punctation on basal halves moderately dense (i=1–1.5d), sparse on apical halves (i=2–4d).

Structure. Head wide (length/width ratio = 0.96–0.97). Eyes convergent below (UOD/LOD = 1.10–1.18). Clypeus ½ below suborbital tangent, apicolateral margins strongly 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 2–4 teeth. Metapostnotum elongate (MMR ratio = 1.08–1.17), posterior margin rounded or weakly angled onto posterior surface. Propodeum with oblique carina very weak, lateral carina weak, not reaching dorsal margin.

MALE. Similar to female except for the usual secondary sexual characters and as follows. Length 3.97– 4.21 mm; head length 1.25–1.32 mm; head width 1.32–1.37 mm; forewing length 3.26–3.66 mm.

Colouration. Head and mesosoma more bluish. Flagellum with ventral surface and tarsi brownish yellow. Tegula brown.

Pubescence. Lower paraocular area obscured by tomentum. Clypeus, and supraclypeal area partially obscured by tomentum. S2–S4 apical portions and S5 lateral portion with moderately dense erect hairs (1–1.5 OD).

Surface sculpture. Mesoscutum, mesepisternum and metasomal terga polished. Mesoscutal punctation moderately sparse on disc between parapsidal lines (i=1–2d), closer laterad of parapsidal lines (i=1–1.5d) and on anterolateral portions (i≤d). Hypoepimeral area and mesepisternum with distinct punctures (i≤d). Metapostnotum with irregular longitudinal rugae, posterior margin rounded. Metasomal terga with basal punctation moderately dense (i=1–1.5d), apical impressed areas impunctate.

Structure. Head wide (length/width ratio = 0.95–0.96). Eyes strongly convergent below (UOD/LOD ratio = 1.48–1.55). Antennal sockets distant (IAD/OAD> 1.4). Frontal line carinate, ending 2 OD below median ocellus. Pedicel subequal to F1. F2 length 2.0X F1. F2–F10 moderately short (length/width ratio = 1.33–1.60). Metapostnotum moderately elongate (MMR ratio = 1.20–1.37), posterior margin sharply angled onto posterior surface.

Terminalia . S7 with median lobe wide, strongly clavate, apex broadly truncate ( Fig. 149F ). S8 with apicomedial margin strongly convex ( Fig. 149F ). Genitalia as in Fig. 149D–E . Gonobase with ventral arms narrowly separated. Gonostylus small, dorsal setae elongate. Retrorse lobe wide, elongate, rounded apically.

Range. Southern British Columbia south to southern California , east to Utah ( Fig. 150 ).

Additional material examined. CANADA: BRITISH COLUMBIA: 38♀ Okanagan-Similkameen Reg. Dist., Oliver, Ripley Lk. , N43.2432 W119.6329, 925 m, 12.vii.2008 (L. R. Best) ; 17♀ Okanagan- Similkameen Reg. Dist., Oliver , Ripley Lk., N43.2435 W119.6324, 925 m, 13.vii.2008 (L. R. Best) ; 1♀ Pitt Meadows , N49°14´59´´ W122°43´02´´, comm. cranberry field, “Hopcott” wpt, 5.vii.2003 (C. Ratti) ; 3♀ Thetis Lake Regional Park, ~ 60 km W Victoria, N48°28´00.9´´ W123°27´58.6´´, 30.vi.2005 (E. Elle) ; USA: CALIFORNIA : 1♂ Los Angeles Co., N34.0974 W118.8134, 30–31.v.2008 (S.W. Droege); [ PCYU] ; 1♀ Mariposa Co., 1.5 mi SE Ostrander Rocks , 11S N4173061 E273096, 2114 m, 18–19.vii.2005 (H.W. Ikerd & E. Stephens) ; 1♀ Mariposa Co., 1.7 mi SEbyE Ostrander Rocks , 11S N4173300 E273625, 2091 m, 3.vii.2005 (H.W. Ikerd) ; 1♂ Mariposa Co., Sunrise Tr., 1.4 mi NE Bunnell Pt. , 11S N4181564 E282926, 2412 m, 8.ix.2004 (E. Rentz) ; 1♀ Mariposa Co., Yosem. Vly., El Capitan Mdw. , 11S N4178388 E267563, 1202 m, 1.vi.2005 (E. Stephens & H. Briggs); [ BBSL]; OREGON : 1♀ Lane Co., nr Mcreadie Hot Springs, Hwy 58, E. of Oak Ridge , 27.vii.2001 (L. Packer); UTAH : 1♀ Kane Co., Lick Wash 12S N4135503 E395058, 11.vi.2002 (L. Topham) ; 1♀ Kane Co., 0.61 mi SSW Cougar Knoll , 12S N4128373 E487269, 7.ix.2000 (M. Sunseri); WASHINGTON : 1♀ Okanagan Co., 1.5 mi E Bailey Mountain , 11U N5389141 E294833, 4.vii.2004 (J. Wilson & L. Wilson) ; 1♀ Okanagan Co., 0.7 mi SW Middle Mountain , 11U N5373331 E346958, 28.vi.2004 (L. Wilson); [ PCYU] .

Floral records. AIZOACEAE : Mesembryanthemum crystallinum , ANACARDIACEAE : Malosma laurina , APIACEAE : Heracleum maximum , ASCLEPIADACEAE : Asclepias fascicularis , A. speciosa , ASTER- ACEAE: Achillea millefolium , Anthemis cotula , Chrysothamnus viscidiflorus , Cichorium intybus , Corethrogyne , Crepis vesicaria , Erigeron divergens , E. strigosus , Ericameria bloomeri , Eriophyllum confertiflorum , Helenium bigelovii , Helianthus annuus , Picris echioides , Pseduognaphalium stramineum , Senecio spartioides , Solidago canadensis salebrosa , S. californica , S. spectabilis confinis , Stephanomeria , BORAG- INACEAE: Cryptantha muricata , C. intermedia , BRASSICACEAE : Brassica , Sisymbrium , Stanleya pinnata , CAPRIFOLIACEAE : Sambucus nigra cerulea , CARYOPHYLLACEAE : Stellaria media , CONVOLVU- LACEAE: Convolvulus arvensis , ERICACEAE : Arctostaphylos nevadensis , A. glauca , Rhododendron occidentale , FABACEAE : Lotus glaber , L. strigosus , Lupinus , FAGACEAE : Quercus chrysolepis , HYDROPHYLLACEAE : Eriodictyon trichocalyx , Nemophila menziesii , Phacelia distans , P. heterophylla , P. minor , P. ramosissima , LAMIACEAE : Monardella linoides stricta , Trichostema lanceolatum , LILIACEAE : Nolina parryi , LOASACEAE : Mentzelia laevicaulis , NYCTAGINACEAE : Mirabilis laevis , ONAGRACEAE : Camissonia bistorta , C. campestris , Clarkia williamsonii , PAEONIACEAE : Paeonia brownii , PAPAVERACEAE : Argemone polyanthemos , Eschscholzia californica , POLEMONIACEAE : Eriastrum virgatum , Gilia tenuiflora , POLYGONACEAE : Eriogonum davidsonii , E. fasciculatum , E. gracile , E. nudum , E. wrightii subscaposum , PORTULACACEAE : Calandrinia ciliata , RANUNCULACEAE : Delphinium , Ranunculus californicus , RHAMNACEAE : Ceanothus parvifolius , C. soredatus , Frangula californica , ROSACEAE : Adenostoma fasciculatum , A. sparsifolium , Heteromeles arbutifolia , Malus , Potentilla glandulosa , Prunus armeniaca , P. dulcis , P. persica , Spiraea , SALICACEAE : Salix laevigata , S. lasiolepis , SCRO- PHULARIACEAE: Cordylanthus nevinii , Keckiella ternata , Penstemon grinnellii , P. palmeri , P. rostriflorus , P. spectabilis , Sairocarpus nuttallianus , Scrophularia californica , TAMARICACEAE : Tamarix , ZYGO- PHYLLACEAE: Larrea tridentata .

Biology. Bohart, 1941: (stylopization, as sp. near nevadensis ).

Comments. Common.

Figures

FIGURE 148. Lasioglossum nevadense (Crawford). Female (A) lateral habitus; (B) dorsal habitus; (C) face. Scale bars, A–C = 1 mm.

FIGURE 149. Lasioglossum nevadense (Crawford). 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 150. Distribution of Lasioglossum nevadense (dark grey) and L. nigroviride (light grey).