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Discover Life 162 kinds match:
Lasioglossum abanci  [popup] female
Lasioglossum achilleae  [popup] female
Lasioglossum acuminatum  [popup] female
Lasioglossum acuminatum  [popup] male
Lasioglossum admirandum  [popup] female
Lasioglossum alachuense  [popup] female
Lasioglossum albipenne  [popup] female
Lasioglossum albohirtum  [popup]
Lasioglossum anomalum  [popup] female
Lasioglossum apocyni  [popup] female
Lasioglossum apopkense  [popup] female
Lasioglossum arantium  [popup] female
Lasioglossum ascheri  [popup] female
Lasioglossum athabascense  [popup] female
Lasioglossum athabascense  [popup] male
Lasioglossum atwoodi  [popup] female
Lasioglossum batya  [popup] female
Lasioglossum birkmanni  [popup] male
Lasioglossum birkmanni  [popup] female
Lasioglossum birkmanni  [popup] female
Lasioglossum birkmanni  [popup] male
Lasioglossum boreale  [popup] female
Lasioglossum boreale  [popup] male
Lasioglossum bruneri  [popup] female
Lasioglossum callidum  [popup] female
Lasioglossum carlinvillense  [popup] female
Lasioglossum cattellae  [popup] female
Lasioglossum ceanothi  [popup] female
Lasioglossum cephalotes  [popup] female
Lasioglossum cinctipes  [popup] female
Lasioglossum cinctipes  [popup] male
Lasioglossum clarissimum  [popup]
Lasioglossum clematisellum  [popup]
Lasioglossum coeruleum  [popup] female
Lasioglossum comagenense  [popup] female
Lasioglossum coreopsis  [popup] female
Lasioglossum coriaceum  [popup] female
Lasioglossum coriaceum  [popup] male
Lasioglossum creberrimum  [popup] female
Lasioglossum cressonii  [popup] female
Lasioglossum curculum  [popup] female
Lasioglossum disparile  [popup]
Lasioglossum dreisbachi  [popup] female
Lasioglossum eleutherense  [popup] female
Lasioglossum ellisiae  [popup] female
Lasioglossum ephialtum  [popup] female
Lasioglossum fattigi  [popup] female
Lasioglossum fedorense  [popup] female
Lasioglossum flaveriae  [popup] female
Lasioglossum floridanum  [popup] female
Lasioglossum forbesii  [popup] female
Lasioglossum forbesii  [popup] male
Lasioglossum foveolatum  [popup] female
Lasioglossum foxii  [popup] female
Lasioglossum foxii  [popup] male
Lasioglossum furunculum  [popup] female
Lasioglossum fuscipenne  [popup] female
Lasioglossum fuscipenne  [popup] male
Lasioglossum georgeickworti  [popup] female
Lasioglossum gotham  [popup] female
Lasioglossum halophitum  [popup] female
Lasioglossum hartii  [popup] female
Lasioglossum hemimelas  [popup] female
Lasioglossum heterognathum  [popup] female
Lasioglossum hitchensi  [popup] female
Lasioglossum illinoense  [popup] female
Lasioglossum imitatum  [popup] female
Lasioglossum impavidum  [popup]
Lasioglossum incompletum  [popup]
Lasioglossum inconditum  [popup] female
Lasioglossum inconditum  [popup] male
Lasioglossum izawsum  [popup] female
Lasioglossum katherineae  [popup] female
Lasioglossum knereri  [popup]
Lasioglossum laevissimum  [popup] female
Lasioglossum lepidii  [popup] female
Lasioglossum leucocomum  [popup] female
Lasioglossum leucozonium  [popup] female
Lasioglossum leucozonium  [popup] male
Lasioglossum leviense  [popup] female
Lasioglossum lineatulum  [popup] female
Lasioglossum lionotum  [popup] female
Lasioglossum lionotum  [popup] male
Lasioglossum longifrons  [popup] female
Lasioglossum lusorium  [popup] female
Lasioglossum lustrans  [popup] female
Lasioglossum lustrans  [popup] male
Lasioglossum macoupinense  [popup] female
Lasioglossum macoupinense  [popup] male
Lasioglossum marinum  [popup] female
Lasioglossum michiganense  [popup] female
Lasioglossum microlepoides  [popup]
Lasioglossum miniatulum  [popup] female
Lasioglossum nelumbonis  [popup] female
Lasioglossum nelumbonis  [popup] male
Lasioglossum nevadense  [popup]
Lasioglossum nigroviride  [popup] female
Lasioglossum novascotiae  [popup] female
Lasioglossum nymphaearum  [popup] female
Lasioglossum nymphale  [popup] female
Lasioglossum oblongum  [popup] female
Lasioglossum obscurum  [popup] female
Lasioglossum oenotherae  [popup] female
Lasioglossum oenotherae  [popup] male
Lasioglossum paradmirandum  [popup] female
Lasioglossum paraforbesii  [popup] female
Lasioglossum paraforbesii  [popup] male
Lasioglossum pectinatum  [popup] female
Lasioglossum pectinatum  [popup] male
Lasioglossum pectorale  [popup] female
Lasioglossum pectorale  [popup] male
Lasioglossum perparvum  [popup]
Lasioglossum perpunctatum  [popup] female
Lasioglossum pictum  [popup] female
Lasioglossum pilosum  [popup] female
Lasioglossum planatum  [popup] female
Lasioglossum platyparium  [popup] female
Lasioglossum platyparium  [popup] male
Lasioglossum pruinosum  [popup] female
Lasioglossum puteulanum  [popup]
Lasioglossum quebecense  [popup] female
Lasioglossum quebecense  [popup] male
Lasioglossum raleighense  [popup] female
Lasioglossum reticulatum  [popup] female
Lasioglossum rozeni  [popup] female
Lasioglossum rufulipes  [popup] female
Lasioglossum sedi  [popup] female
Lasioglossum semicaeruleum  [popup]
Lasioglossum sheffieldi  [popup] female
Lasioglossum simplex  [popup] female
Lasioglossum smilacinae  [popup] female
Lasioglossum sopinci  [popup] female
Lasioglossum sopinci  [popup] male
Lasioglossum stuartense  [popup] female
Lasioglossum subversans  [popup] female
Lasioglossum subviridatum  [popup] female
Lasioglossum subviridatum  [popup]
Lasioglossum succinipenne  [popup] female
Lasioglossum surianae  [popup] female
Lasioglossum swenki  [popup] female
Lasioglossum swenki  [popup] male
Lasioglossum tamiamense  [popup] female
Lasioglossum tarponense  [popup] female
Lasioglossum taylorae  [popup] female
Lasioglossum tegulare  [popup] female
Lasioglossum tenax  [popup] female
Lasioglossum testaceum  [popup] female
Lasioglossum texanum  [popup] female
Lasioglossum texanum  [popup] male
Lasioglossum timothyi  [popup] female
Lasioglossum trigeminum  [popup] female
Lasioglossum truncatum  [popup] female
Lasioglossum truncatum  [popup] male
Lasioglossum versans  [popup] female
Lasioglossum versatum  [popup] female
Lasioglossum vierecki  [popup] female
Lasioglossum viridatum  [popup] female
Lasioglossum weemsi  [popup] female
Lasioglossum wheeleri  [popup] female
Lasioglossum zephyrum  [popup] female
Lasioglossum zonulum  [popup] female
Lasioglossum zonulum  [popup] male


REMAINING (number with state)
Abdomen, T1, pattern and proportion of the upper surface hidden by appressed, short, flattened, densely branched hairs lying prone or nearly prone on the segment, as opposed to the long upright hairs always present - NOTE: not to be confused with the fan of hairs at base of the surface facing the propodeum
 None (112)
 Small patch or line on the far sides of the segment - Can be just a small patch with scattered appressed hairs (23)
Abdomen, T2, pattern and proportion of the upper surface hidden by appressed, short, densely branched, flattened hairs lying prone or nearly prone on the segment, as opposed to the long upright hairs always present
 B. Small triangular patches on the far lateral sides of the segment, usually about the area in size of the propodeal triangle - Can be just a small patch with scattered hairs and there may be a thin line of hairs along the base of the tergite (97)
 A. None (68)
 C. Appressed hairs present EXTENSIVELY across the segment, density may vary, but the hairs are not restricted to the far sides (5)
Abdomen, T3, percent of the upper surface hidden by appressed, short, flattened, densely-branched hairs lying prone or nearly prone on the segment, as opposed to the long upright hairs always present
 B. Small triangular patches on the far lateral sides of the segment, usually about the area in size of the propodeal triangle - Can be just a small patch with scattered hairs and there may be a thin line of hairs along the base of the tergite (91)
 A. None (59)
 C. 10-25 percent of segment hidden, appressed hairs spaced across MUCH of the segment, though perhaps not uniformly (48)
 D. 25-50 percent of segment hidden, appressed hairs spaced across MUCH of the segment, though perhaps not uniformly (42)
 E. over 50 percent of segment hidden (27)
 F. L. imitatum, a common eastern species - Unique in that the bright white appressed hairs are all aligned longitudinally and are UNIFORMLY and REGULARLY and widely spaced in parallel with one another across the entire segment (1)
Abdomen, T4, percent of the upper surface hidden by appressed, short, densely-branched, flattened hairs lying prone or nearly prone on the segment, as opposed to the long upright hairs always present
 A. None (61)
 C. 10-25 percent of segment hidden, appressed hairs spaced across MUCH of the segment, though perhaps not uniformly (58)
 D. 25-50 percent of segment hidden, appressed hairs spaced across MUCH of the segment, though perhaps not uniformly (55)
 B. Small triangular patches on the lateral sides of the segment - Can be just a small patch (53)
 E. over 50 percent of segment hidden (47)
 F. L. imitatum, a common eastern species - Unique in that the bright white appressed hairs are all aligned longitudinally and are UNIFORMLY and REGULARLY and widely spaced in parallel with one another across the entire segment (1)
Abdomen, upperside or tergites, color
 DARK-colored - Usually dark brown to nearly black, but at times with slight overtones of very dark red and in some individuals metallic glintings of green or blue visible in good light (127)
 YELLOW or ORANGE, usually bright, but in some species slightly dulled by obscuring dark patches (17)
EXPERIENCED USERS - An initially difficult to figure out character - Thorax, propodeum, presence of a carina or raised line forming a set of upward facing loops just below the rear edge of the propodeal triangle where the edges of the rear face of the propodeum join the triangle, there may or may not be a carina lining the entire length of the rear face of the propodeums border
 Surface SMOOTH, no raised lines or carinae (120)
 Raised lines or carinae V-SHAPED, usually connected to a raised line or carina separating the rear and the lateral face of the propodeum (28)
 Carinae U-SHAPED to saucer-shaped, usually NOT connected to carinae separating the lateral and rear faces of the propodeum (15)
EXPERIENCED USERS - Thorax, degree of surface roughness or rugosity of the upper part of the mesepisternum - Because categories are not clearly defined you will usually want to click on at least 2 categories when scoring your specimen, particularly for intermediate categories
 B. Surface cross-hatched with SLIGHTLY RAISED lines or scattered bumps that create a slightly rough surface (91)
 A. SMOOTH, with NO raised areas or roughness on the surface (88)
 C. Surface CONTINUOUSLY rough with no flat areas, but not extremely rugged as in category D (47)
 D. Surface EXTREMELY RUGGED, with no flattened areas and the surface angled and faceted, good examples include L. bruneri and L. cressonii in the East (19)
FemFemale, L. leucozonium vs L. fuscipenne ale, L. admirandum, L. paradmirandum, L. viridatum, - This group is tricky to identify and as a group are usually called the L. viridatum group. Identification will be updated soon.
 L. fuscipenne - Dorsal triangle with a tangle or raised lines running from the base towards the rim, however these lines do not extend to the rim and there is a clear smooth bare area across the entire rim, the raised lines appear more like branched roots than parallel straight lines - The humeral angle of the pronotum clearly sharply angled, forming a clear 90 degree or less angle - In direct comparison this species pits slightly smaller and not as bold or deep, particularly on the abdomen (1)
 L. leucozonium - Striations on dorsal triangle portion of the propodeum form clear, nearly straight, parallel, raised lines that go all the way to the rim - The humeral angle of the pronotum slightly rounded over and that angle clearly greater than 90 degrees - In direct comparison this species has bold deep pits, particularly on the abdomen (1)
Female, L. admirandum vs. L. trigeminum - A very tricky pair to tell apart, there is often overlap between the two in these characters and direct comparisons with known specimens is usually required
 L. admirandum - In direct comparison T-1 hair fans more extensive and luxuriant with a relatively narrow section where hair is absent at the top - Face slightly longer with clypeus projecting further below the invisible line running between the bottoms of the compound eyes - Front trochanters very thin and elongate at least 2x as long as wide - Striations on the propodeal triangle run from the base to the rim or just prior to the rim (1)
 L. trigeminum - In direct comparison T-1 hair fans less extensive and sparser with a relatively wide at the top where her hair is absent, this Without hair nearly approaching the extent of the fans on the side - Face slightly shorter with clypeus projecting only slightly below the invisible line running between the bottoms of the compound eyes, although in both species this can be often difficult to judge - Front trochanters relatively wide but not as wide as Lasioglossum callidum usually less than 2x as long as wide - Striations on the propodeal triangle never reach to the rim and often only extend about two thirds of the way (1)
Female, L. admirandum, L. paradmirandum, L. viridatum, - This group is tricky to identify and as a group are usually called the L. viridatum group. Identification will be updated soon.
 L. admirandum (1)
 L. paradmirandum (1)
 L. viridatum (1)
Female, L. alachuense vs L. tarponense
 L. alachuense - Tibiae and tarsi of legs yellow, the remaining sections usually brown - Mesepisternum slightly rough with no pits - Stigma of the wing is a dark honey color - Head round - Size is larger about the same as L. zephyrum (1)
 L. tarponense - Legs largely to entirely yellow - Mesepisternum while heavily lined is smooth and upon close inspection pits are visible - Stigma of the wing is strikingly dark brown, nearly black - Head slightly elongated - Size is small about the same as L. admirandum (1)
Female, L. albipenne, L. creberrimum, L. halophitum
 L. albipenne - Wings with tiny white hairs that make them appear MILKY - Scutum while somewhat dulled by fine, crosshatched, microscopic lines, still readily reflects light - Scutum base color steel blue - In comparison the pits on the scutum are large - Pits on scutum are spaced averaging about 0.75-1.5 pit diameters apart in the center of the segment - Hair fan on T1 dense and forming a tight, complete fan - In comparison, larger (1)
 L. creberrimum - Wing hair golden-brownish - Scutum reflects no light and is very heavily cross-hatched by microscopic lines - Scutum base color is a dull green - In comparison the pits on the scutum are very small - Pits on scutum are CLOSELY spaced averaging about 0.5 to one pit diameter apart in the center of the segment - Hair fan on T1 dense and forming a tight, complete fan - In comparison, smaller (1)
 L. halophitum - Wing hair golden-brownish - Scutum reflects no light and is very heavily cross-hatched by microscopic lines - Scutum base color varies from green to green-blue to blue - In comparison the pits on the scutum are very small - Pits on scutum are WIDELY spaced averaging well over 2 pit diameters apart in the center of the segment - Hair fan on T1 quite sparse but covers a large portion of the segment - In comparison, larger (1)
Female, L. apocyni vs all others
 Others do not have this combination (114)
 L. apocyni - Small - Head is squarish - Clypeus almost dead flat and may even appear subtly concave - Cheek is often quite broad, but some individuals approach a more normal width - Mandibles somewhat longer than normal - Striations on propodeal triangle weak and usually only extend about half way - Head and cheek very similar in appearance to L. heterognathum but hypostomal area not widely spreading (1)
Female, L. apopkense vs L. illinoense - Both about the same size and with clear u-shaped propodeal loops
 L. apopkense - Pits in the center of the scutum averaging greater than 2 pit diameters apart - Mesepisternum highly lined or tessellate but smooth, without any rugged surface sculpturing - Occurring primarily in the Deep South (1)
 L. illinoense - Pits in the center of the scutum averaging 0.75 to 1.5 pit diameters apart - Mesepisternum very rugose, heavily sculpturing, the upper portion not forming any particular pattern but towards the anterior and ventral portions strong raised striations usually appear - Occurring throughout much of the East (1)
Female, L. arantium, L. nymphale, L. pictum, L. testaceum
 L. nymphale - Raised line running up the sides of the rear face of the propodeum reaching only half way or less - The mesepisternum is heavily pitted - The density of pits on the scutum always less than 1 pit diameter apart - Told from the has no yellow along the rim of the clypeus, no pits or only a few vague ones on the mesepisternum, pits on scutum relatively more widely spaced often exceeding one pit diameter - The only difference between this species and L. pictum is the presence of yellow on the rim of the clypeus (1)
 L. testaceum - Raised line running up the sides of the rear face of the propodeum curving over at the very top but absent over the center leaving the central part of the rim curving smoothly over the edge - Has no yellow along the rim of the clypeus - No pits or only a few vague ones on the mesepisternum - Pits on scutum relatively more widely spaced often exceeding one pit diameter (1)
Female, L. athabascenses vs L. fuscipenne
 L. athabascenses - A more northern species - Carinae or raised lines that mark the border between the rear and lateral faces of the propodeum rise less than half way up from the base towards the propodeal triangle - Pronotal collar obtuse and slightly rounded at the tip, but the angle still quite noticeable and strong - Pitting on the scutum denser in comparison with pits up towards the anterior edge, near the head, overlapping they are so dense (1)
 L. fuscipenne - A more southern species - Carinae or raised lines that mark the border between the rear and lateral faces of the propodeum rise far more than half way up from the base towards the propodeal triangle - Pronotal collar very sharply angled to form a right angle turn or something very nearly so - Pitting on the scutum less dense in comparison with pits up towards the anterior edge, near the head, while very close do not overlap (1)
Female, L. boreale vs L. quebecense, head, antenna, color
 Primarily dark brown with half or less yellow, that yellow usually a dull yellow-orange (3)
 BRIGHT yellow with a narrow strip of dark brown below (1)
Female, L. boreale, L. birkmanni, L. foxii, L. macoupinense
 L. birkmanni - Tough to tell from L. macoupinense - Mesepisternum smooth or nearly so, shining usually with visible pits, but these sometimes hard to see - Scutellum with a clearly heavily pitted center line with regions of lower pit density on either side - Face clearly as wide or wider than long, never appearing longer than wide - Small, 5-6,5mm (1)
 L. boreale - Mesepisternum roughened with lines and markings, has no pits - Scutellum uniformly pitted throughout with a heavily pitted center line with regions of lower pit density on either side - Large, 7-8mm (1)
 L. foxii - Mesepisternum roughened with lines and markings, has no pits - Scutellum with a clearly heavily pitted center line with regions of lower pit density on either side - Small, 6-7.5mm (1)
 L. macoupinense - Tough to tell from L. birkmanni - Mesepisternum smooth or nearly so, shining, with clear visible pits - Scutellum with a clearly heavily pitted center line with regions of lower pit density on either side - Face can appear as wide as long, but usually is slightly longer than wide - Small 6-7mm (1)
Female, L. carlinvillense, L. ellisiae, L. lepidii, L. tegulare - A difficult to separate group where their ranges overlap
 L. carlinvillense - Currently known only from a small region in Illinois, likely to occur over a broader region in the Mid-West - A tiny bit smaller than the others - Leg, hind tibia, inner spur , UNIQUE in that the inner spur has only 2 teeth or branches along its side while the others have 3 through 4 , these teeth are small and the spur is often difficult to see (1)
 L. ellisiae - A northern species, occurs in Canada, New England, and south along the Appalacian chain - Most likely to be confused with L. tegulare and very difficult to separate the two - Proper lighting is key to identification, light should be shining from one side of the specimen or show microtopography well - L. ellisiae has a mesepisternum with almost no surface roughness, which doesn t mean that it is not still heavily tessilated or lined with microscopic lines, L. tegulare has enough of a rough surface that it will cast tiny shadows from the ridges and bumps present if light comes from the side, the best place to look is on the mound at the upper end of the mesepisternum, the difference is quite subtle compared to highly sculptured species like L. cressonii, consequently, it is usually the case that one cannot be definitive unless you have comparative material (1)
 L. lepidii - Possibly restricted to Florida, but likely extends at least along the coast outside of the state - Only L. puteulanum is also in the area, if the head and thorax of the specimen is all blue then it is L. puteulanum, if is all green then it is L. lepidii, if it is a mix of blue and green then it could be either - Head with an increased density of small appressed white hairs in the paraocular area, these do not hide the integument from sight, but are significantly denser than in L. puteulanum....can be subtle (1)
 L. puteulanum - A southern species, presently not known from further north than North Carolina - UNIQUE in that some individuals have overall blue coloration of the head and thorax, unfortunately, both L. tegulare and L. lepidii can have significant amounts of blue in these areas at times and some specimens may be impossible to tell apart (1)
 L. tegulare- Occurs widely throughout the region but diminishes in numbers further into the deep South - Note, that some individuals have significant amounts of blue in them making them impossible to tell from L. puteulanum (1)
Female, L. cattellae vs L. surianae
 L. cattellae - Upper side of abdomen always dark - Clear white patches of appressed hairs on T2 and T3 - In comparison larger (1)
 L. surianae - Upper side of abdomen orange-yellow to somewhat dark, not many specimens have been seen, clypeus may have a purplish sheen - Only scattered appressed hairs on T2 or T3 - Restricted to Florida - In comparison, smaller (1)
Female, L. cattellae vs L. tenax - Extremely similar species
 L. cattellae - Fan of hairs on the surface of T1 that faces the propodeum complete and extensive - Thorax color gold-green - More southern in distribution - Slightly larger in comparison (1)
 L. tenax - Fan of hairs on the surface of T1 that faces the propodeum not quite complete usually with a small gap at the top, the overall fan is only sparsely haired - Thorax color dark blue - Far northern in distribution but with specimens from the Smoky Mountains - Slightly small in comparison (1)
Female, L. cattellae, L. zephyrum, L. smilacinae
 L. cattellae - Rare - Striations on dorsal triangle of propodeum reaching to or nearly to rim - Pits on supraclypeus fewer than 40 and less regularly spaced - Tends to be slightly smaller and face with the usual amount of hair - Mesepisternum nearly smooth, very glossy and reflective with only a small amount of surface sculpturing (1)
 L. smilacinae - Uncommon - Striations on dorsal triangle of propodeum usually fairly short, other than the median striation, reaching a little more than half way to rim - Pits on supraclypeus about 40 more or less and regularly spaced - Tends to be larger with the usual amount of hair on the face - Mesepisternum roughened and divided by a network of reticulated raised lines causing the segment to reflect relatively little light (1)
 L. zephyrum - Uncommon to regular - Striations on dorsal triangle of propodeum short on either side of the central striation reach half or less of the distance to rim - Supraclypeus with more than 40 regularly spaced minute pits - Tends to be larger and face hairier - Mesepisternum nearly smooth, very glossy and reflective with only a small amount of surface sculpturing (1)
Female, L. cinctipes vs L. pectorale
 L. cinctipes - Scutellum divided longitudinally by a dense line of pits, the 2 halves very sparsely pitted in their centers - Larger 8-9.5mm more the size of L. sensu strictu - Mesepisternum clearly heavily reticulated with raised lines, but those lines not as tall as the raised striations of the propodeal triangle - The rim of T2 with a fair number of microscopic pits, you will need a good light and microscope to see this character (1)
 L. pectorale - Scutellum uniformly pitted across the entire segment - Smaller 6-7.5mm, more the size of most of the metallic green and blue Lasioglossums - Mesepisternum very coarsely sculptured the raised lines about the same height as the striations on the propodeal triangle - The central depressed rim of T2 with no pits not even microscopic ones (1)
Female, L. cinctipes vs L. quebecense
 L. cinctipes - Scutellum relatively shiny, pits dramatically less dense in the center of the halves, those pits usually more than 2 pits apart - Longitudinal length of the propodeum usually less than the longitudinal length of the scutellum - The striations of the dorsal portion of the propodeum usually are all complete, reaching the rim of the top of the propodeum and are the SAME height from base to rim - T2-3 usually with prominent bands of white appressed hairs that form a band across the entire base of the segment or sometime just patches to the sides show if the tergite above laps over too far - Head relatively wider (2)
 L. quebecense - Scutellum dull, crossed with many fine lines, pits only slightly less dense in the center of the halves, those pits usually only 0.5 -1.5 pits apart - Longitudinal length of the propodeum usually equal to or more than the longitudinal length of the scutellum - The individual ridges of the striations of the propodeal triangle often are incomplete diminishing rapidly in height about half way and devolving into a reticulated network of raised lines that are much less in height than where the striations originate from the base, those reticulations usually reach right to the rim - T2-3 with no bands of white appressed hairs that form a band across the base of the segment, rarely there will be some hairs on the far sides, and often there is a faint band of tan hairs along the sides of the rims of T2 and T3 - Head more elongate (1)
Female, L. cinctipes vs L. truncatum
 L. cinctipes - Lateral angles of the pronotal collar profile clearly obtuse - Rim of T2 with clear and numerous pits, though at a slightly lower density than the center of the segment (1)
 L. truncatum - Lateral angles of the pronotal collar with a 90 degree or nearly so sharp angle to them - Rim of T2 without any pits (1)
Female, L. coeruleum vs all others
 Others - Not as stated (114)
 L. coeruleum - A large species which is unique in that the majority of specimens this bee is bright metallic Ceratina blue throughout the entire body, including the abdomen, however, in some specimens including, but not restricted to, old ones, the metallic blue sheen of the abdomen has greatly faded, fortunately, in almost all cases there is some residual blue overtones to the bare reddish abdomen, which completely lacks appressed hairs, such as that will never be found in other specimens (1)
Female, L. coreopsis, L. creberrimum, L. longifrons - All with relatively long heads and a scutum so heavily lined that it appears beaded and reflecting no light
 L. coreopsis - Pitting on scutum spaced far on average more than 2 pit diameters apart - Hair fan on the base of T1 complete or with only a very tiny opening at the top - Subantennal sutures roughly the same length as the suture bordering the supraclypeus and the clypeus - Widely distributed throughout the East - In comparison smaller (1)
 L. creberrimum - Pitting on scutum spaced, on average, far LESS than 2 pit diameters apart - Hair fan on the base of T1 complete to slightly open at the top - Subantennal sutures slightly shorter than the suture bordering the supraclypeus and the clypeus - Distribution primarily restricted to the southern coastal plains - In comparison larger (1)
 L. longifrons - Pitting on scutum spaced far on average more than 2 pit diameters apart - Hair fan on the base of T1 WIDELY open at the top, the gap often as large at the patches to the sides - Subantennal sutures longer than the suture bordering the supraclypeus and the clypeus or about the same - Distribution primarily restricted to the southern coastal plains - In comparison smaller (1)
Female, L. creberrimum, L. pilosum, L. pruinosum, L. raleighense, L. tamiamense - Species with long-heads, densely pitted, heavily lined, dull scutums
 L. creberrimum - Abdomen dark, with relatively few hairs, appressed hairs on T4 scattered and integument readily visible - Minute hairs on wing tan to brown - Pits on T1 minute, so small as to be easily missed in poor light, dense toward base but absent or only with a few scattered ones near the rim - Pitting on scutum and scutellum dense in spots but in centers of these segments there are places where the pits are clearly not touching one another (1)
 L. pilosum - Abdomen usually with clear metallic reflections, very hairy, appressed hairs on T4 dense and usually completely obscuring the surface, note that old individuals may have lost some of this hair - Minute hairs on wing tan to brown - Pits on T1 small to minute, relatively dense throughout most of the segment but there are clear linear patches of low pit density away from the center line and slightly back away from the rim - Pitting on scutum and scutellum very dense most pits touching one another, but in most individuals there are at least a small area in the center of these segments where at least some of the pits don t touch one another - Hair on the scutum often with a distinct golden cast, in the other species this tends to be white or tan (1)
 L. pruinosum - Abdomen usually with clear metallic reflections, very hairy, appressed hairs on T4 dense and usually completely obscuring the surface, note that old individuals may have lost some of this hair - Minute hairs on wing BRIGHT WHITE, causing the wing to appear milky - T1 pitting pattern similar to L. pilosum but often with pit size being microscopic - Pitting on scutum and scutellum dense in spots but in centers of these segments there are places where the pits are clearly not touching one another (1)
 L. raleighense - Abdomen dark, hairy to moderately hairy, appressed hairs on T4 usually moderately dense nearly completely obscuring the surface, note that old individuals may have lost some of this hair - Minute hairs on wing tan to brown - Pits on T1, clear, nearly as large as those on scutum, abundant, nearly touching and uniform in density all the way to the rim - Pitting on scutum and scutellum uniformly dense with ALMOST ALL PITS TOUCHING ONE ANOTHER (1)
 L. tamiamense - Abdomen dark, with relatively few hairs, appressed hairs on T4 scattered and integument readily visible - Minute hairs on wing tan to brown - Tricky to differentiate from L. creberrimum, but restricted to far southern Florida, pits on scutellum uniformly dense whereas in L. creberrimum the pit density clearly declines towards the center of the segment, pits on scutum and scutellum in comparison smaller, overall size slightly smaller in comparison - Pits on T1 minute, so small as to be easily missed in poor light, dense toward base but absent or only with a few scattered ones near the rim - Pitting on scutum and scutellum uniformly dense but pits so small that while it may appear that way most pits are not touching one another (1)
Female, L. disparile, L. subviridatum, L. smilacinae
 L. disparile - UNIQUE, above the T1 hair fan is a hairless gap and then above that is a latitudinal band of hairs that runs across the segment, this band of hairs is composed of hairs similar to that of the hair fan in size, density and the fact that they similarly lie flat and sits just below where the segment bends to the dorsal surface and is much wider than long - T1 hair fan open at the top - In direct comparison slightly smaller than L. smilacinae (1)
 L. smilacinae - There is no band of hairs above the T1 hair fan - T1 hair fan either complete or with only a small opening at the top, the opening always LESS wide than the patches of hair to the sides - In direct comparison slightly larger and the abdomen hairier (1)
 L. subviridatum - There is no band of hairs above the T1 hair fan - T1 hair fan very WIDELY open at the top, the opening usually wider than the patches of hair to the sides - In direct comparison, smaller and the abdomen with only a small amount of appressed hairs on either side of the segments when compared to L. smilacinae (1)
Female, L. dreisbachi, L. viridatum group, L. lineatulum, L. novascotiae
 L. viridatum group - Mesepisternum without the extreme contrast between the upper and lower portions and in most cases without any pits - T4 varying between a small amount to completely covered with short, fat, appressed hairs, but such hairs always present - In direct comparison smaller - Found throughout the region (3)
 L. dreisbachi - UNIQUE, surface roughness of the mesepisternum very rough on the upper half but smooth on the lower section along with some scattered pits, the line between the two sections dramatic, as that of a rocky coastline meeting the ocean - T4 with scattered short, fat, appressed hairs, integument clearly visible and hairs covering less than 25 percent of the surface - In direct comparison smaller - Rare northern species (1)
 L. lineatulum - Mesepisternum without the extreme contrast between the upper and lower portions and in most cases without any pits - T4 with greater than 50 percent of the surface covered in short, fat, appressed hairs, often nearly complete - In direct comparison larger - Extends well south in the mountains (1)
 L. novascotiae - Mesepisternum without the extreme contrast between the upper and lower portions and in most cases without any pits - UNIQUE, T4 with no short, fat, appressed hairs - In direct comparison larger - Far northern species (1)
Female, L. foveolatum and L. ceanothi vs all others
 Others - Not as stated (79)
 L. ceanothi - Known only from the type specimen which is from Wayne County, NC - Almost exactly the same as L. foveolatum except supraclypeus not as swollen, supraclypeus with a few pits in the center, and pitting in the parocular region almost as dense as that surrounding the antennal bases, in L. foveolatum those pits decrease in density greatly in the parocular region (1)
 L. foveolatum - Moderately small bee - Clearly swollen supraclypeus which has only a few large pits and metallic purple sheen in center - L. versans has similar supraclypeal structure but L. versans has more pits, less purple, and is less swollen as well as overall bigger and with striations that only go about half way down the propodeal triangle (1)
Female, L. foxii vs L. inconditum
 L. foxii - Best distinguished by the fact that the striations of the propodeal triangle do not reach the rim and that there is always a prominent smooth area crosshatched by microscopic lines before the rim In comparison, the head is NEARLY as broad as long, the scutum is SLIGHTLY more lined making it look duller, the hairs along the pronotal lobe and the area of the underside of the cheek nearest in proximity to the pronotum are denser and under 40X these hairs have a much higher rate of branching making them look like fat white hairs rather than thin hairs with scattered branches as in L. inconditum (1)
 L. inconditum - Best distinguished by the fact that the striations of the propodeal triangle reach all the way to the rim - In comparison, the head is CLEARLY longer than broad, and the scutum is SLIGHTLY less lined at least in the center, making it look shinier (1)
Female, L. illinoense vs all others
 Others - Not as above (141)
 L. illinoense - This is a small species about the size of L. imitatum, L. hitchensi - The quickest way to separate out this species from the others listed below is the presence of 2 u-shaped or horseshoe shaped raised carinae on either side of the rim of the propodeal triangle, most people have an initially difficult time detecting this feature, but once learned it works well for this often very common species - UNIQUE to this species but often cumbersome to detect is that the front coxae are expanded outward looking more like a set of female breasts rather than the usual flatter aspect of all the rest of the Lasioglossum species (1)
Female, L. laevissimum, L. planatum, L. smilacinae - Very similar large species
 L. laevissimum - T2 with absolutely NO pits in the slightly depressed portion of the segment bordering the rim, the depressed area is hard to see at times but its about one-third of the segment and in all species is hairless - Mesepisternum with no pits at all (1)
 L. planatum - T2 depressed rim has scattered minute pits, these may be hard to see without good light and a good microscope or a goopy specimen - Mesepisternum with either no pits or just a few along the border with the metepisternum - Overall impression of the abdomen, on average, being the least hairy of the three (1)
 L. smilacinae - Depressed rim of T2 has scattered minute pits, these may be hard to see without good light and a good microscope or a goopy specimen - Mesepisternum with scattered pits THROUGHOUT, these may not be obvious at first due to a fair amount of surface sculpturing but can be readily seen at high magnification (1)
Female, L. leucocomum vs L. pilosum - Nearly identical and expect there to be some specimens that cannot be separated and separation best done with reference material handy
 L. leucocomum - Head, clypeus, go to the rim of the clypeus, go the edges of the rim and observe the corner where the perimeter of the clypeus returns towards the head, this corner is CLEARLY OBTUSE, this is the most definitive character - Thorax, scutum, hairs are ALWAYS WHITE to OFF-WHITE - In direct comparison, the supraclypeus is slightly shorter, T1 has a different pattern to the microscopic markings, and individuals are SLIGHTLY smaller - There appears to be some association with this species and sandy areas (1)
 L. pilosum - Head, clypeus, go to the rim of the clypeus, go the edges of the rim and observe the corner where the perimeter of the clypeus returns towards the head, this corner is ROUGHLY AT RIGHT ANGLES, making the projecting distal end of the clypeus appear to be squared off or rectangular, however, this is not perfect and many specimens have a slightly obtuse angle - Thorax, scutum, hairs OFTEN WITH A GOLDEN HUE, BUT NOT ALWAYS, old specimens and coastal specimens, in particular, may be faded from being in the sun - In direct comparison, the supraclypeus is slightly longer and more pitted, T1 has a different tesselation pattern, and individuals average slightly larger - There appears to be less of a restriction and association with this species and sandy areas, but it usually present and can be more common than L. leucocomum in sandy areas (1)
Female, L. leucozonium vs. L. zonulum
 L. leucozonium - Thorax, pronotal collar, the lateral angles located along the upper edges to either side of the back of the head are generally OBTUSE , to the interior of the collar running from the pronotoal angle towards the head there is only mild rounded over ridge - Abdomen, S2, along the very edge of the rim of S2, and projecting beyond it, is a DENSE ROW of very short appressed bright white hairs, these hairs are branched but that is only visible under high magnification and are the same type of hairs as found in patches on the tergites, these hairs are also extremely short, only about an eight as long as the other hairs on the sternite (1)
 L. zonulum - Thorax, pronotal collar, the lateral angles of the pronotal collar located to either side of the back of the head are strong and sharp, forming RIGHT ANGLES or nearly so, to the interior of these angles running from the angle towards the head there is an abrupt, sharp, PROMINENT RIDGE - Abdomen, S2, with only a few or no white hairs along the rim and these never forming a complete band (1)
Female, L. leviense vs L. admirandum, L. lineatulum, L. oblongum, L. viridatum group
 L. admirandum, L. lineatulum, L. oblongum, L. viridatum group - Tarsi and basitarsi of the hind legs all brown or at most with yellowish basitarsi and yellow only at the apical and basal tips of the tarsi (4)
 L. leviense - Tarsi of the hind legs primarily yellow with a brown spot in the center, basitarsi completely yellow - Southern coastal plain (1)
Female, L. nigroviride vs all others
 Others do not have this combination (91)
 L. nigroviride - The largest and darkest of all eastern metallic Lasioglossum - Abdomen with almost no hairs, and no hint of a colored rim - Mesepisternum glossy and CLEARLY pitted (1)
Female, L. nymphale vs L. vierecki
 L. nymphale - Hair on thorax and head clearly WHITE (1)
 L. vierecki - Hair on thorax and head clearly GOLDEN YELLOW (1)
Female, L. oblongum vs L. obscurum - Note, size, abdomen color, and hair pattern are very, very similar
 L. oblongum - Thorax color varies from a beautiful deep blue to green-blue - Mesepisternum fairly rough and rugose, with absolutely no pits - Acaranarium fan on T1 much reduced usually only thin patches of hair on either side of center - Pits on scutum widely separated in the center of the segment but very crowded and spaced far less than 1 pit diameter apart between the sides and the parapsidal lines (1)
 L. obscurum - Thorax color is green-blue - Mesepisternum relatively smooth, somewhat shiny, and with clear pits - Acaranarium fan on T1 thicker and moderately complete with a wide opening at top, much more robust in comparison - Pits on scutum widely separated both in the center of the segment and between the sides and the parapsidal lines (1)
Female, L. pectorale vs L. truncatum
 L. pectorale - Smaller, 7-9mm - Humeral angle on the pronotum obtuse - Base of T2-3 with only relatively sparse scattering of short, fat, prone, white hairs on the far sides - Overall impression is that of a metallic member of Lasioglossum (1)
 L. truncatum - Larger, 9-10mm - Humeral angle on the pronotum only a bit greater than 90 degrees - Base of T2-3 with what are usually unbroken stripes across the segment of dense short, fat, prone, white hairs - Overall impression and often confused with Lasioglossum sensu strictu (1)
Female, L. perpunctatum, L. pilosum, L. pruinosum, L. succinipenne
 L. perpunctatum - Thorax hairs are white to off-white - T2 pit density CLEARLY drops to scattered pits as you go toward the rim - Rear face of the propodeum somewhat smooth but there are faint, but noticeable, striations fanning out from the lowest or basal point of the segment and spreading out like a vase upwards - Antennal flagellar segments dark with a slight lightening of the undersides toward the tip - Pit density in the center of the scutum clearly very dense averaging less than 0.5 pit diameter apart - Supraclypeus often mounded up and with a slight purplish tint - In comparison to L. pilosum, head less elongate and integument of tergites less dulled by microscopic lines (1)
 L. pilosum - Thorax hairs are often, but not always yellow-gold - T2 pits go clearly and with uniform density to the rim - Rear face of the propodeum smooth and without any raised reticulations or at most some vague unclear surface sculpturing - Antennal flagellar segment coloration variable, running from completely dark to bright yellow on the undersides - Pits density in the center of the scutum clearly very dense averaging less than 0.5 pit diameter apart - Be careful of worn, old individuals, the hair will fade to white and hair density on the abdomen will decrease (1)
 L. pruinosum - Thorax hairs are white to off-white - T2 pits decrease somewhat towards the rim but not as dramatic as L. perpunctatum and L. succinipenne - Rear face of the propodeum smooth and without any raised reticulations - Antennal flagellar segments yellowish underneath dark on top, not as dramatic a contrast as in L. succinipenne - Pit density in the center of the scutum clearly WELL SEPARATED averaging over 1 pit diameter apart (1)
 L. succinipenne - Thorax hairs are white to off-white - T2 pits go clearly and with uniform density to the rim - Rear face of the propodeum STONGLY RETICULATED with a web of raised reticulated lines, particularly towards the base - Antenna flagellar segments clearly yellow on the underside starting about the second flagellar segment - Pits density in the center of the scutum clearly very dense averaging less than 0.5 pit diameter apart - A western prairie species that only barely makes it into the region (1)
Female, L. pilosum vs L. pruinosum
 L. pilosum Florida race Similar to other Eastern bees, but with less hair on the top of abdominal segments 2 and 3 (1)
 Pilosum Eastern bees scutal hair gold or yellowish; scutum green-gold; wing hairs brown-yellow; top of second abdominal segment almost always with a band of hair going across the base; scutum pits nearly touching 0.25 pits apart and relatively large (1)
 Pruinosum scutal hairs bright white; scutum steel blue; top of second abdominal segment with hair usually only on the sides; scutum pits more widely separated, 0.5-0.75 pits apart and relatively small; wing hairs white (1)
Female, L. sensu strictu, abdomen, T1, surface facing propodeum, pattern of UPRIGHT hairs and presence of distinct central bare spot - Note that there is often a fan of long PROSTRATE hairs intermixed with the upright hairs, these should be ignored
 No distinct bare spot, sparsely scattered hairs (6)
 Arrowhead-shaped bare spot with an opening at top that is narrower than fringe of hairs on either side (1)
 Bare spot completely encircled by hairs (1)
 Bare spot encircled by hairs but with an opening at top that is as wide or wider than fringe of hairs on either side (1)
 Bare spot encircled by hairs but with an opening at top that is narrower than the width of the fringe of hairs on either side (1)
Female, L. smilacinae vs L. hitchensi, L. versatum, and L. viridatum group, L. callidum
 L. hitchensi, which was formely known as L. atlanticum, L. versatum, L. viridatum, L. callidum - Mesepisternum ABSENT of any pits - L. admirandum and L. viridatum group distinctly smaller - Rim of T2 in L. versatum and L. versatum usually, but not always, with distinct bands of translucent yellow-brown to clear edge (6)
 L. smilacinae - Mesepisternum with scattered pits THROUGHOUT, these may not be obvious at first due to a fair amount of surface sculpturing but can be readily seen at high magnification - Rim of T2 as dark as rest of segment or with no distinct band of translucent yellow-brown to clear edge or only the tiniest sliver that is easy to overlook (1)
Female, L. smilacinae vs L. lineatulum and L. novascotiae
 L. lineatulum and L. novascotiae - Scutum pit density very low, very widely spaced apart, pits between the parapsidal lines and tegulae never touching and usually averaging further than 2 pit diameters apart (2)
 L. smilacinae - Scutum pit density relatively high, pits between the parapsidal lines and tegulae touching or very nearly touching (1)
Female, L. swenki vs all other black thorax species, abdomen, color
 Abdomen entirely black or a very dark reddish brown (76)
 T1-3 a slightly darkened red color, one of the few species with extensive, short, thick, prone, white hairs that line the edge of the scutum and across the cheek (1)
Female, L. tenax, L. obscurum, L. zephyrum
 L. obscurum - UNIQUE, pits on scutum very widely spaced both in the center of the segment and between the parapsidal lines and the tegulae - Striations of the propodeal triangle extend about 75 percent of the way or more to the rim - Abdomen with no appressed hairs (1)
 L. tenax - Pits between the tegulae and the parapsidal lines touching or nearly so - Striations of the propodeal triangle extend about 75 percent of the way or more to the rim - Abdomen with at least some appressed hairs at the far sides of T2 and T3 (1)
 L. zephyrum - Pits between the tegulae and the parapsidal lines usually not closer but far closer together than in the center of the scutum - UNIQUE, striations of the propodeal triangle extend less than half way to the rim - Abdomen with at least some appressed hairs at the far sides of T2 and T3 (1)
Female, L. versatum vs L. laevissimum
 L. laevissimum - Rims of T2-4 tend to be same color as the body or are narrow and clear to very slightly yellowish-brown - Pits on T2 largely to entirely disappear in the last one-third of the center of the segment near the rim - T1 hair fan usually only very slightly open at the top (1)
 L. versatum - Rims of T2-4 tend to have a strong yellow component to them, are comparatively wide the very outer edge is usually clear and largely without color - Pits on T2 in comparison denser and decrease in density only somewhat towards the rim, although beware that the pits near the rim can be microscopic and you will need a good light and microscope to detect them - T1 hair fan usually with a hairless opening at the top that is about the same width as the hair patches on the sides (1)
Female, L. versatum vs L. lineatulum
 L. lineatulum - Pit density of the scutum very low, average pit spacing far more than 2 pits apart, pit density between the tegulae and the parapsidal lines also widely spaced - Pits on T2 in comparison less dense and fall off to only scattered pits towards the rim as in L. versatum these pits can be microscopic - Overall impression is one of a slightly glossier bee (1)
 L. versatum - Pits in the center of the scutum moderately spaced averaging about 1-2 pit diameters apart from one another, pit density between the tegulae and the parapsidal lines dense most pits touching or nearly so - Pits on T2 in comparison denser and decrease in density only somewhat towards the rim, although beware that the pits near the rim can be microscopic and you will need a good light and microscope to detect them - Overall impression is a slightly duller species with not as much light reflecting from the surface of the scutum and the abdomen (1)
Female, L. versatum vs L. viridatum group
 L. viridatum group - Small like L. imitatum, L. illinoense, L. hitchensi - Pits on T2 in comparison less dense and fall off to only scattered pits towards the rim as in L. versatum these pits can be microscopic - Rims of T2-4 tend to be same color as the body or are narrow and clear to very slightly yellowish-brown - In most individuals the tegula is yellow (3)
 L. versatum - Large to moderately-sized like L. lineatulum, L. cressonii, L. oblongum - Rims of T2-4 tend to have a strong yellow component to them are comparatively wide the very outer edge is usually clear and largely without color - In most individuals the tegula is brown - Pits on T2 in comparison denser and decrease in density only somewhat towards the rim, although beware that the pits near the rim can be microscopic and you will need a good light and microscope to detect them (1)
Female, Yellow form of L. birkmanni vs selected other species
 Others, including the very common non yellow form of L. birkmanni - Legs vary from dark brown to a dull brown red (26)
 L. birkmanni - Yellow form - All segments of all legs BRIGHT orange-yellow (1)
Female, abdomen, T1, hairs on the base of the segment, on the surface that faces the thorax - Note, these hairs are NOT like the appressed short hairs that are often found on the tergites, particularly T3 and T4, but are thin and similar to the other long hairs on the abdomen, however, what is special about these hairs is that they often form a FAN at the very base of T1, originating from the base of the segment near where it joins the propodeum on the thorax, these hairs are NOT upright and lie on the face of the segment, often the specimen needs to be rotated so that the hairs show up in the microscope light, note that the face holding the hairs can be hidden if the abdomen is not slightly drooping
 COMPLETE - Hairs form a fan across the segment with hairs running from the sides and across the top without any hairless break in the pattern (44)
 PART OPEN - Hairs are present on the sides of the segment and fan upwards but there is a hairless break in the center, this hairless arc in the center is NARROWER than the regions to either side that do have hairs (43)
 WIDE OPEN - Hairs are present on the sides of the segment and fan upwards but there is a hairless break in the center, this hairless arc in the center is WIDER than the regions to either side that do have hairs (30)
 ABSENT - No hairs present as a fan, however, there might be scattered upright hairs (14)
Female, head, supraclypeus, number of pits found within the suture lines that define the sides and bottom of the segment and the upperside defined by the imaginary line running below the lower edge of the bases of the antennal fosssae - which are the holes that the scape silts in
 30-40 (87)
 20-30 (83)
 40 or more (60)
 20 or fewer (46)
Female, legs, front pair, trochanters
 Round to slightly flat and relatively narrow (128)
 Very flat and wide, length less than 2x the width (3)
Female, thorax, pronotum, lateral angle, shape
 Obtuse, rounded over, weakly projecting (120)
 Sharply projecting right angle (45)
Female, wing, weakened transcubital veins - See EXPLAIN for details - Note that males are scored for this character BUT can only sometimes be separated using this character, the weakening of veins is much less obvious, we would suggest that for males you use this only as a secondary character
 BOTH second and third transcubital veins weakened (128)
 Third transcubital vein ONLY weakened (18)
 Wing only has 2 submarginal cells, third transcubital vein weakened (4)
Head, cheek, width relative to the eye - To compare, position head so that your eye sights across the flat face of the bee
 About the same as the eye (114)
 Clearly much wider than eye over 1.2 times (87)
 LESS, than the eye (37)
 HUGE - Over 2 times the width of the eye (6)
Head, clypeus, color
 All Dark (93)
 Yellow or White on rim, can extend to up to half the clypeus (17)
 All yellow (3)
Head, face, dimensions
 Head width and length equal (130)
 Wider than long (111)
 Distinctly longer than wide (39)
Head, hypostomal groove, shape
 Sides parallel or VERY slightly divergent toward the mouth (127)
 Sides CLEARLY and obviously GREATLY diverging towards the mouth (9)
L. comagenense vs L. quebecense
 Comagenense - We have seen the types and at this point we consider this to be the same species as quebecense (1)
 Quebecense (1)
L. forbesii vs L. paraforbesii, face, dimensions
 Moderately elongate (2)
 Short, rounded (2)
L. gotham vs L. smilacinae
 L. gotham - Thorax with a strong greenish cast - Scutum, in comparison, slightly more glossy and less dulled by microscopic lines - T1 fan always part open at the top with the fan hairs originating close to the border of the triangular depresssion at the base of the segment - Possibly restricted to mid-Atlantics woodlands in the spring (1)
 L. smilacinae - Thorax with a strong midnight blue cast - Scutum, in comparison, slightly glossy, dulled by many microscopic lines and reflecting less light - T1 fan complete to barly open at the top and, in comparison less dense with hairs not originating along the border of the triangular depression and consequently the fan hairs are not as long and presenting the fan more circular in outline (1)
L. nelumbone vs all others, propodeum
 Entire surface of propodeum surface is visible, scattered hairs present but most of these thin, long, and sparse (50)
 Propodeal triangle comes to a clear point in the center, striations complete, without noticeable hair, and prominent, remainder of propodeum obscured with a thick coat of gray to off-white, short, thick, prone hairs (3)
L. sensu strictu group - Thorax, propodeum, dorsal triangle
 Ruguloso - Striolate - Weak squiggly lines that do not stand more than a couple of hair widths above the surface (12)
 Smooth and unmarked over entire posterior half (7)
 Strongly striate or reticulate - Bold and often relatively straight lines that stand tall and proud above the surface and extending all the way to the rim (6)
L. texanum versus all others, ocelli, space between the side of the lateral ocelli and the compound eyes
 More than the diameter of an ocelli (123)
 Less than the diameter of half of an ocelli (2)
L. versatum vs L. planatum
 L. planatum - Pits on depressed rim portion of T2 noticeably and CLEARLY less dense than those elsewhere - T2 with moderate to strong metallic reflections - Appressed hairs on the abdomen vary from bright white to off-white - T1 hair fan varies from wide open to open just at the very top, but where it exists it is moderately dense - Striations on the propodeal triangle simple, largely unbranched, but in comparison less tall, less wide and less bold - Scutum color varies from sky blue to green-blue but not gold-green - In direct comparison smaller (1)
 L. versatum - Pits on T2 run at about the same density from the base to the rim of the segment, pits on the depressed rim often slightly smaller is diameter - T2 without strong or often any metallic reflections - Scutum color usually, but not always, a golden green color - Striations on the propodeal triangle simple, largely unbranched, relatively thick, relatively tall, those in the center going about 75 percent of the way to the rim - Appressed hairs are tan or off-white rather than bright white - In direct comparison one of the largest of the metallic Lasioglossums (1)
Male, L. acuminatum, L. coriaceum, L. pectinatum A set of long mandibled males
 L. acuminatum Mandibles dark - Labrum dark Gena or cheek wide and SOMETIMEs with a very prominent projection very similar to H. ligatus females - Anterior edge of scutum RAISED above the level of pronotal collar - Mesepisternum dull and slightly rugose pits absent - Rear basitarsi yellow (1)
 L. coriaceum Mandibles dark or some dull yellow or gold infused along the mid-portions - Labrum dark - Gena or cheek wide, and slightly angular in outline - Anterior edge of scutum dead flush with the level of pronotal collar - Mesepisternum dull and slightly rugose pits largely obscured Rear basitarsi dark (1)
 L. pectinatum Mandibles yellow Labrum part or all yellow Gena or cheek wide, and slightly angular in outline Anterior edge of scutum raised above the level of pronotal collar Mesepisternum shiny and pits clearly visible Rear basitarsi dark (1)
Male, L. athabascense vs selected others, S5, tufts of long erect hair on sides, clearly longer than other hairs on segment
 Absent (7)
 Present (2)
Male, L. birkmanni vs L. foxii vs L. macoupinense
 L. birkmanni - Dark form - Labrum appears bright yellow, with a prominent bump in the center occupies half or more of the latitudinal width of the segment - Mesepisternum smooth and relatively shiny with obvious pits - Propodeal triangle and the rear face of the propodeum both tessellated with fingerprint like inscribed lines, neither with pits - In direct comparison, T1 with much finer pits than the other species, which are often nearly impossible to see and may give the impression of debris or mere surface imperfections, not visible under certain angles (1)
 L. foxii - Labrum appears dark brown, with the surface smoothly convex or flat throughout - Mesepisternum irregularly roughened, any pits present well disguised and indistinct as a result - Propodeal triangle with striations limited to the basal half or so, smooth and shiny along the rim, this contrasting with the finely-pitted rear face of the propodeum - In direct comparison, T1 with relatively larger pits than are seen in the other two species, which are visible at most angles under high magnification (1)
 L. macoupinense - Labrum appears amber-brown, with a prominent bump in the center occupies about one third of the latitudinal width of the segment - Mesepisternum only weakly roughened and sometimes slightly shiny, making the pits present easily recognized - Propodeal triangle tessellate at its apex, this contrasting with the slightly more roughened, but unpitted, rear face of the propodeum - In direct comparison, T1 with very fine pits which resemble pinpricks and are often only visible at certain angles under high magnification, these pits smaller than those in L. foxii but slightly more apparent than those of L. birkmanni (1)
Male, L. cinctipes, L. quebecense, L. truncatum
 L. cinctipes - Antennae all brown - Labrum brown - Hind leg tibia all brown - Scutum in comparison not as dulled and lined as in L. quebecense (1)
 L. quebecense - Antennae noticeably yellow underneath - Labrum yellow - Hind leg tibia all brown in dark abdomened individuals or with a small amount of yellow at the ends, in individuals with a good deal of reddish in the abdomen the tibia can also be yellowish particularly at the ends - Scutum very, very dull, reflecting no light, heavily cross-hatched by minute lines (1)
 L. truncatum - Antennae all brown - Labrum yellow - Hind leg tibia with bright yellow apical and basal ends - Tarsal segments a brighter yellow in comparison to the other species - Scutum, in comparison, not as dulled and lined as L. quebecense (1)
Male, L. foxii vs L. inconditum
 L. foxii - Best distinguished by the fact that the striations of the propodeal triangle do not reach the rim and that there is always a prominent smooth area crosshatched by microscopic lines before the rim - In comparison, the head is NEARLY as broad as long, the scutum is SLIGHTLY more lined making it look duller, the hairs along the pronotal lobe and the area of the underside of the cheek nearest in proximity to the pronotum are denser and under 40X these hairs have a much higher rate of branching making them look like fat white hairs rather than thin hairs with scattered branches as in L. inconditum (1)
 L. inconditum - Best distinguished by the fact that the striations of the propodeal triangle reach all the way to the rim - In comparison, the head is longer (1)
Male, L. fuscipenne vs selected others, S2 - 4, rear halves
 Without dense hair patches (7)
 Central area of each segment with dense hairs which lay flat on the surface, clearly denser than the scattered hairs found on most species and largely hiding the surface (1)
Male, L. leucozonium vs L. zonulum, S6
 With inverted v-shaped depression bordered by conspicuous long hairs (1)
 Without v-shaped depression and hairs (1)
Male, head, antenna, length of flagellar segment 2 compared to segment 1 and pedicel combined
 Shorter (12)
 Longer (10)
 Equal (3)
Male, head, clypeus, surface and shape
 Distinctly mounded and usually at least partially dulled by fine lines (8)
 Almost completely flat and highly polished (6)
Male, head, labrum, color
 Brown (22)
 Yellow (15)
Male, head, mandible, length
 Reaching only to or just a bit beyond the far side of the labrum (17)
 Reaching to or nearly to the opposite mandible base (7)
Male, head, mandible, length in relation to opposing clypeal angle - That area of the lateral edges of the clypeal rim that are bent downward
 About equal or barely longer (10)
 Long, obviously exceeding distance (5)
Male, legs, rear pair, basitarsi, color
 Yellow to yellowish orange (15)
 Dark brown (9)
New species from Jason Gibbs revision are being added to the guide and the guide is slowly being overhauled. Some of these species have not been scored for the characters in the guide. By clicking the RECOMMENDED button below you will remove those species that have not been scored at all and decrease some of your frustrations. Note, that species that are scored may not, as of yet, be separable from other species. We are working on that. It will be good to use both this key and Jason s keys to work out the identity of your Lasioglossums.
 RECOMMENDED - Use the species currently with character scorings (140)
 Display the species not currently included (25)
Parasitic Females - Mandibles a simple blade without any additional teeth or lobes
 L. ascheri - Propodeal triangle with striation extending nearly to the rim - Cheeks extremely wide - Mandibles very long and thin, extending nearly to the base of the opposite mandible - The mesepisturnum is distinctly PITTED - Hypostomal cavity edges parallel (1)
 L. cephalotes - Propodeal triangle with striations restricted to the very base of the propodeum, these strations often just small bumpts scattered along the base, extending far less than half-way down the triangle - Cheeks extremely wide, its bottom edge forming a blunt approximately 90 degree angle - Mandibles very long, not far from the the tip the upper edge makes a rapid sinuate transition as the mandible rapidly widens - Width of the clypeus greater than the length of the compound eye - The carinate rim of the hypostomal cavity remains at approximately the same height throughout it length - The clypeus extremely flat and longitudinally short - Mesepisternum very smooth and clearly and densely PITTED - head width 1.802.02 mm (1)
 L. furunculum - Propodeal triangle with striation extending nearly to the rim - Cheek width and length and length of mandible similar to that of non-parasitic species of Dialictus - Pronotal ridge sharply angled and similar to all the parasitic species except L. simplex (1)
 L. lionotum - Propodeal triangle with NO STRIATIONS whatsoever or a few short striations near the base - Cheeks extremely wide, its bottom edge forming a blunt approximately 90 degree angle - Mandibles very long and thin, extending nearly to the base of the opposite mandible - In direct comparison much smaller, the size of L. imitatum - Width of the clypeus than the length of the compound eye - The carinate rim of the hypostomal cavity remains at approximately the same height throughout it length - The clypeus extremely flat and longitudinally short - head width 1.251.30 mm (1)
 L. platyparium - Propodeal triangle with striation extending nearly to the rim - Cheeks extremely wide, its bottom edge forming a blunt approximately 90 degree angle - Mandibles, broad and long, from the tip they widen but then narrow slightly again before widening to the base of the mandible, note, some specimens can have a very minute tooth microscopic in size and no where near the size of non-parasitic species - Width of the clypeus less than the length of the compound eye - UNIQUE, the carinate rim of the hypostomal cavity approximately doubles in height above the surface from the base to the mandibles - The clypeus extremely flat and longitudinally short (1)
 L. rozeni - Propodeal triangle with striation extending nearly to the rim, though the central striations often only reach about half-way, these striations strong and prominent - Cheeks extremely wide - Mandibles very long and thin, widening uniformly from the tip to the base without any abrupt transitions and extending nearly to the base of the opposite mandible - Edges of the hypostomal cavity clearly diverge as they extend to towards the mandibles, the carinate rim remains the same height throughout its length - Mesepisternum not pitted, or only very vagulely so (1)
 L. simplex - Propodeal triangle with striation extending nearly to the rim - Cheek width and length and length of mandible similar to that of non-parasitic species of Dialictus - UNIQUE in that the pronotal ridge is SMOOTHLY ROUNDED similar to non-parasitic species of sub-genus Dialictus (1)
Parasitic Females - Mandibles with a distinct tooth on the upper margin, set slightly back from the tip
 L. curculum - Propdeal triangle with clear and priminent striations - Mandible clearly with a TOOTH similar ot non-parasitic species - Width of the clypeus greater than or equal to the length of the compound eye - Cheeks extremely wide, its bottom edge forming a blunt approximately 90 degree angle - The carinate rim of the hypostomal cavity remains at approximately the same height throughout it length - The clypeus extremely flat and longitudinally short - Told from the similar L. michiganense by the presence of CLEARLY visible pits scattered across the mesepisturnum and no obvious striations present (1)
 L. izawsum - Cheeks moderately wide or similar to non-parasitic species and its bottom edge evenly rounded again similar to other non-parasitic species (1)
 L. michiganense - Propodeal triangle with clear striations - Width of the clypeus less than the length of the compound eye - Cheeks wide, but not greatly wider than that the width of the compound eye - The carinate rim of the hypostomal cavity remains at approximately the same height throughout it length - The clypeus extremely flat and longitudinally short - UNIQUE in the presence of raised vertical striations on the mesepisturnum amidst some vague pits, note that these striations are not as prominent as those found on the propodeal triangle (1)
 L. platyparium - Propodeal triangle with clear striations - Mandibles with only a very tiny tooth, this tooth much smaller than any found in the non-parasitic species and easily overlooked, sometimes with no tooth at all, broad and long, from the tip it widens and then narrows again before widening to the base, note, some specimens can have a very minute tooth microscopic in size and no where near the size of non-parasitic species - Width of the clypeus less than the length of the compound eye - Cheeks extremely wide, its bottom edge forming a blunt approximately 90 degree angle - UNIQUE, in that the carinate rim of the hypostomal cavity approximately doubles in height above the surface from the base to the mandibles - The clypeus extremely flat and longitudinally short - UNIQUE in labrum usually has a PROMINENT projecting bump or mound in the center (1)
Sex, Total number of antennal segments, including the scape and pedicel
 12, female (122)
 13, male (27)
Shortcuts to groups within Lasioglossum - Click on 1 or more groups listed below, hit search, then hit simplify, and more questions will appear - Note that the groups listed below are not all exclusive, but members can partially or completely overlap with other groups - Males of the metallic species have yet to be scored and entered into the system - Be aware that separation of species in the metallic groups are often extremely difficult
 Female, metallic, non-parasitic species in the past classified by Mitchell as Dialictus - Note, males of this group are not yet scored (87)
 All black species, includes all or some members of Dialictus, Evylaeus, Lasioglossum, Sphecodogastra, and Hemihalictus groups (52)
 Lasioglossum sensu strictu - as defined by McGinley - All have only 1 weakened transcubital vein (16)
 Parasitic species - Paralictus, as defined by Mitchell - Note, not all males have been scored and people often miss the fact that females have no scopa, so to be conservative click this box if the bee is metallic (12)
 Sphecodogastra - As defined by McGinley - If you don t know this group then click this box to keep it in the guide (4)
Size - This is a relative measure so you will need some experience with known specimens to use effectively
 Small - Size of L. imitatum, L. illinoense, L. admirandum (45)
 Large - Size of L. bruneri, L. coeruleum, L. cressonii, L. lineatulum (39)
 Moderate - Most species are scored as moderate and large or moderate and small so this is a bet-hedging category (31)
 Very Large - Size of L. sensu strictu like L. fuscipenne, L. leucozonium, L. coriaceum (23)
State or province where bee was collected - Lasioglossum sensu strictu only
 NY (19)
 NH (18)
 Ontario (18)
 VT (18)
 MI (17)
 PA (17)
 ME (16)
 NJ (16)
 New Brunswick (16)
 Nova Scotia (16)
 Quebec (16)
 CT (15)
 MA (15)
 Newfoundland and Labrador (15)
 Prince Edward Island (15)
 RI (15)
 WV (15)
 MD (13)
 WI (13)
 DE (12)
 IN (12)
 VA (12)
 IL (11)
 OH (10)
 GA (9)
 NC (9)
 SC (9)
 KY (8)
 TN (8)
 DC (5)
 AL (3)
 FL (3)
 MS (3)
States or provinces where bee was collected - All species except for Lasioglossum sensu strictu
 Outside of the other states (110)
 NC, SC, GA, AL, MS (91)
 FL (37)
Subgenus
 Dialictus (104)
 Evylaeus (22)
 Lasioglossum (16)
 Hemihalictus (2)
Thorax, color
 Not black - Can be gold, blue, green, to a very dark brown, if dark brown or nearly black then with a strong metallic sheen (94)
 Black (54)
Thorax, mesepisternum, degree of pitting
 ABSENT, no pits present (67)
 OBVIOUS, pits are clearly defined and as easy to detect as those on the scutum (30)
 VAGUE, at certain angles pits can be seen but an initially the segment appears to lack pits (30)
Thorax, propodeum, edge or border between the top face - Also known as the dorsal triangle - And the rear face - At the bottom of which is the attachment to the abdomen
 Edge smooth and rounded over without a raised line along rim, although there may be v- or u-shaped raised lines at the far sides (117)
 Sharp transition, has a raised line - Also known as a carina - That runs along this border but is ABSENT in the CENTER - Be sure to look closely and be precise (20)
 Sharp transition, with a narrow raised line -Carina - Across the ENTIRE edge - Look closely to make sure there is NO break in the center (20)
Thorax, propodeum, raised line - Carina - That separates lateral from rear faces
 Incomplete, reaching only about half way or less to upper surface (105)
 Complete, reaching or nearly reaching dorsal surface (55)
Thorax, propodeum, top surface - Also known as the propodeal triangle - AVERAGE length of striations in the central section as measured from the base towards the rim, IGNORING the one middle stripe that is normally longer than the others
 C. 75% to almost to the edge (100)
 D. All the way to the edge (89)
 B. 50% (51)
 A. Less than 50% of the way (27)
Thorax, scutum, spacing of pits in the area around the center line, hint - Units are in numbers or fractions of pit diameters
 2. 0.5 to 0.75 (88)
 3. 1-1.5 (84)
 4. 1.75-2 (66)
 1. Less than 0.5 (57)
 5. More than 2 (39)
Thorax, scutum, surface reflectivity - Caution, best used after lots of experience
 Semi-glossy, reflective, but not like a mirror (106)
 Flat, dull, lusterless, but surface smooth (95)
 Glossy, shiny, polished (52)
 Beaded, granular, bumpy, opaque (38)
Thorax, tegula, shape
 Oval - Inner and outer margins convex and symmetrical (128)
 Non-oval, outside margin similar to other species, but inner margin flattened to slightly concave with a lobe of the bottom edge projecting inward toward the scutum (7)
Wing, submarginal cells, number
 3 (134)
 2 (4)
zz Dreisbachi, oblongum, viridatum; thorax, side, region from where front wing attaches to where the middle leg attaches, amount of surface roughness - rugosity - Warning, All 3 may be Intergrades of the same species!
 Dreisbachi - rough on upper half, smooth on lower half (1)
 Oblongum - moderate to low rugosity throughout (1)
 Viridatum - very rough throughout (1)