2.5d). Supraclypeal area imbricate, punctures sparse (i=12.5d). Allotype. Michener); 1 Lawrence, Mesoscutum polished, weakly imbricate in part, punctation moderately sparse on medial portion of disc (i=11.5d), dense adjacent to parapsidal lines (laterad and mesad) (id) and reticulate on anterolateral portion. Prepisternum rugulose. F2 length 2.0X F1. Supraclypeal area with punctation moderately sparse (i=12d). mesepisternum distinctly punctate (as in Fig. DISTRIBUTIONHolarctic, being widely distributed in Canada and northern Europe. Life Trans. Antenna dark brown,flagellum with ventral surface yellow-orange. Of st. Louis. Clypeus 1/3 below suborbital tangent, apicolateral margins convergent. Legs brown, except tibiae bases and apices, and tarsi pale brownish yellow. Droege); [PCYU]. Metapostnotum carinate-rugose, apical margin imbricate. Eyes convergent below spur (compare Figs. Inner metatibial spur pectinate, teeth 34, basal Gena narrower than eye. Mandible brown basally, yellow apically. Metasomal terga with apical impressed areas punctate, but narrowly impunctate apically. Apoidea Labrum and mandible infused with yellowish brown. (n=3). with L. versatum and L. callidum. Face imbricate. Male L. birkmanni have shorter

USDA Bee Biology and Systematics Laboratory, Logan Utah. Clypeus below suborbital line. 220); mesoscutum polished-weakly imbricate, punctures moderately sparse between parapsidal lines (i=11.5d) (Fig. Axilla punctate. 86); clypeus quite convex, produced about two-thirds below suborbital line; eyes rather strongly convergent below; mandibles rather slender but quite short; labrum short, not appreciably produced medially; cheeks subequal to eyes in width; lateral ocelli subequally distant from eyes and margin of vertex; basal segment of flagellum very slightly longer than pedicel, following segments considerably longer, blackish above, piceous below; punctures very fine and close above antennae, becoming obscure hut still quite close below, vertex and cheeks substriate; scutum shining, punctures deep and distinct, well separated medially, becoming very fine and close at mid line anteriorly, deeper and more distinct but closely crowded laterally, quite sparse on scutellum on each side of middle; pleura rather coarsely rugosostriate; dorsal area of propodeum quite coarsely and regularly striate, posterior face margined laterally with distinct carinae; wings hyaline, veins pale ferruginous, stigma brownish-ferruginous; tegulae reddish, with yellowish-hyaline anterior and outer margin; legs largely black, but tibiae with a small, basal, yellowish spot, and basitarsi almost entirely yellow, the more apical tarsal segments darkened; abdominal terga rather deeply and distinctly but very finely punctate, punctures well separated but not sparse on basal segment, becoming finer, closer and more obscure on the more apical segments, terga 2-4 with rather indefinite, whitish, basal fasciae, discal pubescence suberect, pale brownish; apical margin of sternum 5 nearly straight, 6 with a triangular, shining and bare, apical area which is fringed basally with rather dense pubescence; apical margin of tergum 7 not noticeably reflexed; gonostylus simple, short, slightly dilated and rounded apically; no ventral, retrorse lobe evident. Discover Life bee species guide and world checklist, Ascher and Pickering. Metasomal terga dark brown. National Biological Information Infrastructure. Pubescence.

5F and 5H). Female L. birkmanni have denser punctation on supraclypeal area (id). deep, close basally; T2T6 apical impressed areas impunctate. Metasomal terga polished, apical impressed areas weakly coriarious; punctures dense, obscure Metasomal terga polished, punctation Head width 1.351.65 mm. Length 4.85.1 mm.

Michener); 1 Lawrence, 3.vii.1952 (C.D. Pronotum smoothly rounded. Head and mesosoma with sparse plumose hairs. 13.ix.1913 (A.T. Evans); [UCMC]; NORTH CAROLINA: 1 E. of Charlotte, Hwy 24/27, N35.22754 W080.5583, T2T4 with sparse basolateral tomentum. Head round (length/width ratio = 1.02). Head very wide (length/width ratio = 0.930.94). S3S5 apicolateral portions with subappressed hairs (11.5 OD). Metasomal sterna with plumose 141. faintly dusky. Surface sculpture.

; black, with apical half of clypeus pale yellow; pubescence whitish, rather dense on head and thorax; length and breadth of head equal (similar to fuscipenne, fig. Metafemoral scopa of dense plumose hairs. They are most similar to L. callidum and L. versatum. Subgenus: Hemihalictus. Metapostnotum moderately elongate (MMR ratio = 1.27), posterior margin narrowly rounded onto posterior surface. Propodeal lateral surface with mixed simple and plumose hairs. 4F, 6F), supraclypeal punctation sparse (i=12.5d), pronotum smoothly rounded dorsolaterally, and Extracted from: Charles Robertson (1900). MALE. 2011. 222). Reprinted with permission from: Mitchell, T.B. Upper paraocular area and frons punctate-reticulate. Droege); [PCYU]; SOUTH CAROLINA: 1 Chesterfield Co., N34.5403 W080.23182,18.v.2006 (S.W. Male L. trigeminum can be recognised by the following diagnostic combination: face with dense tomentum (Fig.220B); flagellomeres long (length/width ratio = 1.461.81) (Fig. (n=5). Pterostigma brown. Paratypes. Propodeal lateral carina nearly reaching dorsolateral slope. lineolate. Flagellomeres, except F1 moderately elongate, F2 shorter than F1 and pedicel combined, much shorter than scape. Tegula amber to brownish yellow. Etymology.

Colour. Mandible short, reaching opposing clypeal angle. This species is similar to divergens, but has a round rather than long head, additionally the pits on mesepisturnum are less prominant, and the mesonotum has more extensive gray fuzz on the anterior edge this often going about half way down the segment in the center, slightly smaller, 5-6m.

Holotype. Clypeus polished, basal margin weakly imbricate, punctation moderately sparse (i=12d). Male L. versatum have less dense facial tomentum and denser punctures on T2. Genital capsule as in Fig. North Carolina Agricultural Experiment Station Technical Bulletin No. Examination of voucher material from the behavioural studies performed by Michener (1966) revealed that at least some of the bees he studied correspond to L. trigeminum and not L. versatum. Metanotum imbricate. with dorsolateral slope imbricate. Hypoepimeral area imbricate. Ocelli normal. Michener); 2 Lawrence, 8.vi.1952 (C.D. Osenton); 1 Pr. setae on the gonostylus (Fig. Tegula 18B). Metapostnotum carinate-rugose basally, apical Antennal sockets distant (IAD/OAD >1.3). MALE. Length 4.845.81 mm; head length 1.421.58 mm; head width 1.511.70 mm; forewing length 3.573.93 mm. It barely reaches the United States, with the only positive records from Maine and New York; July to October. Wing membrane hyaline, Discover Life bee species guide and world checklist, Ascher and Pickering. Hymenoptera similar to L. macoupinense in some characteristics but can be easily separated by the pronotum and inner metatibial Clypeus with apical half blackish brown. USA: FLORIDA: 1 Leon Co., Tall Timbers Res. Wing mm. Structure.

Extracted from: Gibbs, J., Packer, L., Dumesh, S. and Danforth, B. N. 2013. Eyes strongly convergent below (UOD/LOD ratio = 1.54).Clypeus 2/3 below suborbital tangent, apicolateral margins weakly convergent. Head and mesosoma black. 141. Mesoscutum polished; punctures dense laterally (id), distinctly separated between parapsidal lines (i=12d). Colouration. Propodeum weakly rugulose laterally, posterior surface weakly imbricate. . Colouration. Gena narrower than eye. Structure. Gonostylus small, dorsal setae elongate. Extracted from Jason Gibbs. The collection of this species on certain spring flowers, such as Salix, Prunus and Pyrus, suggests an earlier seasonal appearance in flight than the records show. Mesepisternum upper portion weakly rugulose and lower portion imbricate. Lower paraocular area and gena with moderately dense subappressed tomentum. Colour. T2T3 with basolateral patches of dense tomentum. 76B). F2F10 moderately elongate (length/width ratio = 1.461.81). 1960 Bees of the Eastern United States. Mesoscutellum similar to mesoscutum, submedial punctation moderately sparse (i=12.5d). Pp 1-116.

Legs dark brown, except tarsi, bases Antenna black, except ventral surface of flagellum brown. Halictidae obscure. Some Illinois Bees. 221); tegula and tarsi brownish yellow; metapostnotum with weakly angled onto posterior propodeal surface; metasoma terga with sparse basolateral tomentum; and T2 apical impressed area with narrow impunctate margin. Structure. Head and mesosoma pale green or blue. Pterostigma Metasoma dark brown, terga and sterna with apical margins translucent brownish yellow. Eyes convergent below (UOD:LOD = 1.461.50). and apices of pro- and mesotibiae yellow, protibia largely yellow-testaceous. Revision of the metallic Lasioglossum (Dialictus) of eastern North America (Hymenoptera: Halictidae: Halictini.) Head and mesosoma black. posteromedially. Wing membrane subhyaline, venation and pterostigma yellowish brown. Length 4.90 mm; head length 1.51 mm; head width 1.46 mm; forewing length 3.45 mm. teeth much longer than width of rachis. Discover Life bee species guide and world checklist, Ascher and Pickering. Length 5.26.6 mm. 1.09) (Figs. Lasioglossum Ocellocular area densely punctate (id). Surface sculpture. Gena and postgena FLOWER RECORDSAster, Barbarea, Fagopyrum, Lotus, Melilotus, Solidago and Tragopogon. Both sexes of L. birkmanni have head shorter (L/W ratio = 0.940.99) (Figs. Redescription. DNA Barcode. most species, except L. birkmanni. Propodeum with dorsolateral slope and posterior propodeal surface rugose. Pubescence. Diagnosis. Male. Lasioglossum macoupinense can be easily distinguished from Droege);[PCYU]. Legs dark brown, except medio- and distitarsi reddish brown. 222). Pronotum smoothly rounded dorsolaterally. Sci. Lower paraocular area punctation dense (id). (UOD:LOD = 1.221.31). Propodeal lateral carina not reaching dorsal margin, oblique carina low, Antennal sockets close (IAD/OAD < 0.5). Male L. callidum have wide protrochanter (Fig. Length 8 mm. Propodeum imbricate-tessellate, with fine vertical carinulae extending to dorsolateral Metasomal terga with moderately sparse, fine hairs. 4A, 6A). Clypeus apical half yellow. Hymenoptera margin weakly imbricate. Antennocular area punctation moderately dense (i=11.5d).

Description. Diagnosis. fine and moderately dense throughout (i=11.5d). Structure. Metepisternum with upper half rugoso-carinulate, lower half imbricate. Propodeum Antenna black, except ventral surface of flagellum reddish brown. T2 apicolateral and T3T4 apical margins with sparse fringes. Metasomal terga black-brown, apical margins pale brown. Head width 1.241.41 mm. The specific epithet is taken from Latin word for triplet and refers to the close similarity of this species

Reprinted with permission from: Mitchell, T.B. Gonobase with ventral rim narrowly separated. Female L. trigeminum can be recognised by the following diagnostic combination: head wide (length/width ratio = 0.930.94) (Fig. Gena narrower than eye. Range. Inner metatibial spur pectinate with 46 branches. Wing membrane hyaline. 10.viii.2006 (J. Gibbs); 1 S. of Bryson City, Bryson City & Queen Branch Rds., N35.28377 W083.4872, 8.viii.2006 (J.Gibbs); 1 Richmond Co., N36.8628 W079.83642, 19.v.2006 (S.W. Sta., 28.iii.1986 (B. Alexander); DISTRICT OF Similar to female except for the usual secondary sexual characters and as follows. Subgenus: Leuchalictus. Metasomal terga polished; punctures Available. Head long (L/W ratio = 1.061.09). Head length 1.421.65 mm. Head long (L/W ratio = 1.021.06). 1960 Bees of the Eastern United States. Both sexes of L. macoupinense can be recognised by the combination of head long (L/W ratio = 1.02 FEMALE. Head and mesosoma with moderately dense woolly hairs (11.5 OD),longest on genal beard, metanotum, and mesopleuron (22.5 OD). Droege); 1 Richmond Co., N36.8937 W079.81004, 19.v.2006 (S.W. S7 with median lobe columnar, apex rounded (Fig. Eyes convergent below (UOD/LOD ratio = 1.241.32). Legs brown; tarsi reddish brown. Propodeum with oblique carina weak, virtually absent, lateral carina not reaching dorsal margin. T1 with The latter name has been regularly applied to three distinct but closely related species (Gibbs 2010b, see discussion below). scopa. Terminalia. Halictidae Mesepisternum smooth, polished, distinctly punctate (i=12d). sparse, erect plumose hairs. 218B); paraocular area with moderately dense tomentum; protrochanter narrow; mesoscutum polished posteriorly, punctures moderately sparse between parapsidal lines (i=11.5d) (Fig. National Biological Information Infrastructure. Apoidea Insecta 223). Michener); [SEMC]; MARYLAND: 1 Anne Arundel Co., N39.08223 W076.7883, 1415.vi.2005 (P. Flagellum with ventral surface brownish yellow. USA: GEORGIA, Chatham Co., N32.1323 W081.1336, 22.x.2009 (C. Haynes); [PCYU]. FEMALE. Dull white. Multiple sequences.

Frontal line carinate, ending 2 OD below median ocellus. Metapostnotum moderately truncate (MMR ratio = 1.271.45), posterior margin narrowly rounded onto posterior surface. Volsella roughly ovoid.

Mesoscutum between parapsidal lines flattened. Gena lineolate. It is more slender, the abdomen more shining, less closely punctured, antennae testaceous eneath, a pale spot on tubercles, tibiae pale at base and apex. 222. Wing length 4.04.1 Surface sculpture. COLUMBIA: 1 N76.95472 W038.905, 26.v.2005 (S. Rudy); [PCYU]; ILLINOIS: 1 Carlinville, N39.2787 Life Pedicel shorter than F1. T2 basolaterally, T3 and T4 largely covered by tomentum, obscuring surface.

USA: DC, FL, GA, IL, IN, KS, MD, MI, NC, NJ, SC, VA, WV. Zootaxa 3672 (1). Metapostnotum incompletely rugoso-carinulate, posterior margin imbricate. Head length 1.351.51 mm. Protibial spur with apical serrations shorter than width of malus. T1 acarinarial fan sparse with wide dorsal opening, intermingled with erect hairs. Maryland south to Georgia, west to Kansas (Fig. Face below eye emargination with tomentum partially obscuring surface, denser on paraocular area.

2.viii.1952 (C.D. Closely resembles the male of H. arcuatus. Droege); [PCYU]; VIRGINIA: 1 Assateague I., N37.9144 W075.3379, 30.vi1.vii.2006 (S.W.Droege); [PCYU]; WEST VIRGINIA: 1 Hampshire Co., N39.30325 W078.4339, 2930.v.2004 (S.W.

S8 with apicomedial margin weakly convex (Fig. Moderately dense. Lateral and posterior surfaces imbricate-tessellate. Lasioglossum W089.8898, 24.vi.2006 (J. Gibbs); [PCYU]; KANSAS: 1 Douglas Co., Lawrence, from nest, vii.1957 (C.D. Mesepisternum polished, distinctly punctate. Postgena weakly imbricate. Pubescence. Lasioglossum (Dialictus) trigeminum Gibbs, new species. testaceous-reddish brown. Mesoscutum polished; punctures dense laterally (id), clearly separated between parapsidal lines (i=1 slope. 7F). Frontal line carinate, ending <2OD below median ocellus. Insecta Retrorse lobe elongate, weakly attenuated, recurved apically. North Carolina Agricultural Experiment Station Technical Bulletin No. 219); mesepisternum rugulose; metapostnotal rugae nearly reaching posterior margin; T1 declivitous surface polished, acarinarial fan with wide dorsal opening; and metasomal terga brown, apical impressed areas densely punctate. MALELength 7-8 mm. Acad. 7A) than do L. macoupinense (Fig. Georges Co., N38.978 W076.7643, 89.ix.2005 (Z. Riegel); [PCYU]; MICHIGAN: 1 Wakefield, Gena and postgena lineolate.

Surface sculpture. Labrum yellow. brown. Propodeum with moderately dense plumose hairs on lateral and posterior surfaces (22.5 OD). USA, Indiana, Jackson Co., N38.8799 W086.056, 26.vii.2003 (S.W. Supraclypeal area imbricate, with sparse, shallow punctures (i=12d). Metasomal terga without apical fimbriae. Brittain and Newton (1934) record leucozonium on the following additional genera: Achillea, Arctium, Centaurea, Daucus, Diervilla, Epilobium, Hieracium, Narcissus, Philadelphus, Prunus, Pyrus malus, Rudbeckia, Salix, Sonchus, Trifolium and Vaccinium. The female of L. pectinatum is superficially length 4.14.8 mm. Revision and reclassification of Lasioglossum (Evylaeus), L. (Hemihalictus) and L. (Sphecodogastra) in eastern North America (Hymenoptera: Apoidea: Halicidae). Zootaxa. National Biological Information Infrastructure.