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30 kinds match

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Agapostemon angelicus  [popup] female
Agapostemon angelicus  [popup] male
Agapostemon coloradinus  [popup] female
Agapostemon coloradinus  [popup] male
Agapostemon fasciatus  [popup] female
Agapostemon fasciatus  [popup] male
Agapostemon femoratus  [popup] female
Agapostemon femoratus  [popup] male
Agapostemon leunculus  [popup] female
Agapostemon leunculus  [popup] male
Agapostemon melliventris  [popup] female
Agapostemon melliventris  [popup] male
Agapostemon mexicanus  [popup] female
Agapostemon mexicanus  [popup] male
Agapostemon nasutus  [popup] female
Agapostemon nasutus  [popup] male
Agapostemon obliquus  [popup] female
Agapostemon obliquus  [popup] male
Agapostemon peninsularis  [popup] female
Agapostemon peninsularis  [popup] male
Agapostemon sericeus  [popup] female
Agapostemon sericeus  [popup] male
Agapostemon splendens  [popup] female
Agapostemon splendens  [popup] male
Agapostemon texanus  [popup] female
Agapostemon texanus  [popup] male
Agapostemon tyleri  [popup] female
Agapostemon tyleri  [popup] male
Agapostemon virescens  [popup] female
Agapostemon virescens  [popup] male


REMAINING (number with state)
Female, A. angelicus and A. texanus vs all others - Thorax, scutum surface - Best viewed under high magnification
 Complex of ridges, pits and reticulations, pits range in size (12)
 A. angelicus and A. texanus - Surface can be relatively smooth in eastern populations and some western populations, all have a regular pattern of 2 sizes of pits, scattered large pits, almost laid out in a grid, and a higher density of smaller pits, about one third the size of the large ones, the spacing of the small pits varies from touching to clearly separated - Large pits often HARD to detect for some people (2)
Female, A. angelicus vs. A. texanus
 A. angelicus - The females of this species can not be reliably distinguished from the females of A. texanus based on morphology. However, the range of A. angelicus is limited to the area West of the Mississippi river, making it impossible to tell the species in that region. (1)
 A. texanus - The females of this species can not be reliably distinguished from the females of A. angelicus based on morphology. As A. texanus has a distribution including East of the Mississippi river, any specimens that are either A. angelicus or A. texanus in this area may be safely regarded as A. texanus. (1)
Female, A. coloradinus vs A. mexicanus - No female specimens of A. mexicanus have been viewed for this guide
 A. coloradinus - More common than A. mexicanus (1)
 A. mexicanus - Rare, has not been collected in the United States but it may occur along the border with Mexico. (1)
Female, A. coloradinus vs A. tyleri
 A. coloradinus - Head, supraclypeus, much smaller medially smooth and shiny area in the center, the remainder of the area appearing heavily marked by faint transverse striations which often intrude upon the medially unpitted area - - Head, Gena, coarser striations that extend along the eye up to the vertex - - Abdomen, T1, appressed, white hair patches are usually longitudinally longer than latitudinally wide, never coming close to meeting in the middle, and sometimes entirely absent - - Wings, larger, and nearly as brownish as those of A. splendens (1)
 A. tyleri -Head , Supraclypeus, larger medially smooth and shiny area , the remainder of the raised area appears smooth or weakly roughened by faint bumpy patterning which does not intrude upon the medially unpitted area - - Head, Gena, finer striations that extend upward along the eye only slightly past halfway, if at all - Abdomen, T1, appressed, white hair patches are latitudinally wider than longitudinally long, nearly meeting in the center - - Wings, smaller and much lighter. (1)
Female, A. coloradinus vs A. virescens - CAREFUL, difficult to separate pair best done with known specimens in direct comparison
 A. coloradinus - Usually less common - In direct comparison, usually averages LARGER, with a FINER and greater density of striations on the underside of the head on either side of the hypostomal cavity - Head, mandible, base, color dark BROWN OR BLACK to, at times, a dark, murky, burnt orange (1)
 A. virescens - Usually more common - In direct comparison, usually very averages SMALLER, with COARSER and less dense striations on the underside of the head on either side of the hypostomal cavity - Head, mandible, base, color, DIRTY YELLOW, at times, can be quite dark but still yellow rather than dark orange (1)
Female, A. fasciatus vs. A. melliventris - Note, A. fasciatus has been recently resurrected as a species
 A. fasciatus - Head, antenna, scape, dark -- Abdomen, tergites, almost entirely dark with the a lightened area usually resticted to just the rim (1)
 A. melliventris - Head, antenna, scape, with yellow markings on the scape, primarily on the front -- Abdomen, tergites, mostly amber collored, sometimes entirely so (1)
Female, A. femoratus vs A. obliquus and A. sericeus, thorax, scutum, surface between parapsial lines
 A. obliquus and A. sericeus - Coarsely punctate, with many pits that are not large enough for the bottom of them to be seen, although the surface may be slightly rugose laterally and apically - Patterning between parapsidal lines largely made up of circular formations (2)
 A. femoratus - Coarsely rugose to areolate, with the patterning enlarged to the point that the bottoms of all or nearly all of the enclosed, pit-like structures are visible and shiny - Patterning between parapsidal lines largely made up of non-circular formations (1)
Female, A. melliventris vs all others, combination of characters
 All others - Scape entirely black or brown - Abdomen either black , metallic green or blue (14)
 A. melliventris - Scape yellow, or partly yellow - Abdominal terga amber to black with T1 usually amber (1)
Female, A. nasutus vs all others
 All others - Thorax, pronotal lobe, apex similarly colored in comparison to the surrounding integument, without a pale yellow or creamy spot- - Head, clypeus, flat in the variably-colored apical rim, or if concave then only very slightly and most often as a result of pitting, rather than a literal dip in the integument, variable breadth, most often only double the clypeal length at most. (14)
 A nasutus -Thorax, pronotal lobe, pale yellow or creamy spot at the apex - - Head, Clypeus, strongly concave medially within the apically yellow rim, considerably broader than long, often more than three times as wide as its length (1)
Female, A. obliquus vs. A. sericeus - CAREFUL, Difficult to separate pair
 A. obliquus - Head, antenae, scape, some specimens uncommonly yellow basally and or apically , when present the yellow is usually at least equal in length to the pedicel or nearly so, although sometimes it may extend up to a third of the scape s length from its base, and sometimes appearing to be a paler brown than is found on the rest of the scape when the yellow integumental color is not present - - Abdomen, T1, pit density just before the apically impressed rim, most often found to be higher than in A. sericeus such that interpit spacing does not exceed one pit diameter except at the farthest lateral sides - -The distribution of A. obliquus is more southwestern than primarily eastern A. sericeus, however both species have been collected in TX and WY (1)
 A. sericeus - Head, antennae, scape, NO specimens with yellow, at most with the integument slightly paled such that it appears a lighter brown than the rest of the scape, although this condition is uncommon - - Abdomen, T1, pit density just before the apically impressed rim most often found to be lower than in A. obliquus such that interpit spacing here will often exceed two pit diameters, CAREFUL as some specimens of A. sericeus have very low interpit spacing similar to A. obliquus - -The distribution of A. sericeus is more eastern than primarily southwestern A. obliquus, however both species have been collected in TX and WY (1)
Female, abdomen, color of integument
 Black, brown, or amber in coloration - With varying levels of slight blue or green metallic sheen, but never approaching that of the head or scutum (9)
 Metallic green or blue - With the same level of metallic sheen seen on the head or scutum, or very nearly so (6)
Female, head, clypeus, color of rim above labrum
 Dark brown to black (10)
 Pale off-white to yellow, although sometimes there is a thin band of dark integument along the rim (5)
Female, head, supraclypeal area, pitting
 Supraclypeal bump medially roughened by transverse striations or heavy pitting, with no central shiny area as a result (14)
 Supraclypeus produced into a strong bump, the pinnacle of which is largely unpitted and unpatterned such that it has a smooth and shiny appearance in comparison to the integument elsewhere on the supraclypeus (5)
Female, hind leg, tibia, hair color
 Hairs on basitibial plate and those proceeding down the front of the tibia darker than hairs on the sides of the tibia and the scopal hairs, dark brown or smoky grey (9)
 All hairs from the basitibial plate down the tibia similar in color with hairs on the sides of the tibia and the scopal hairs, golden to white (7)
Female, scutellum, surface texture, NOT counting the large and areolate patterning along the posterior rim
 Scutellum variably punctate, having pits of many different sizes, with the smallest pits present far more densely in the anterior and often medial portions of the scutellum, sometimes forming a T with a bare and shiny spot to each side (10)
 Scutellum doubly punctate, having both small and large pits, with the smaller pits of roughly equal density throughout ang/tex, obliquus, splendens, tyleri (5)
 Scutellum with all pits of roughly one size and their pit density uniform, except in some specimens where this is a pair of lateral spots where pitting is either less dense or absent, giving these areas a shinier appearance (4)
Female, thorax, propodeum, top center
 With small triangle set within the larger propodeal triangle that is defined by a distinctly different pattern of rugulae than the coarse ones surrounding it, these markings often going in different directions sometimes forming a ridge at the interface - This small triangle sometimes subtle, other times obvious (10)
 Longitudinally striate throughout or all rugulae similar, no distinct triangular area created by different patterns of rugulae (9)
Females, A. melliventris VERSUS A. virescens -- Modified from Mike Arduser Key
 A. melliventris --- Head, clypeus: yellow apically - - Abdomen, tergites: blackish to amber - - Body length: smaller, usually less than 12 mm - - NOTE: A. fasciatus, a former synonym of A. melliventris, has recently been recognized as a separate species. The two can be separated by the color of the scape, which is yellow in A. melliventris but blackish in A. fasciatus. (1)
 A. virescens --- Head, clypeus: blackish in apical half or so - - Abdomen, tergites: blackish - - Body length: usually 12mm, occasionally more - - NOTE: a species similar in appearance to A. virescens is A. coloradinus, a Great Plains species which may overlap in range with A. virescens. Compared to females of A. virescens, females of A. coloradinus have much finer pitting on the tergites, finer striations on the genae, and generally are noticeably larger in size. (1)
Females, A. sericeus VERSUS A. splendens -- Modified from Mike Arduser Key
 A. sericeus --- Thorax, pronotum: with dorso-ventral ridge sharply-edged, and dorso-lateral angle pointed and produced at a distinct right angle in dorsal view - - Wings: usually clear - - Nesting habitat: various - - NOTE: A. sericeus is nearly identical to the western species A. femoratus, and females of the two are easily confused, although the males are easily separated—see male key. Their ranges are mostly separate, but there are a few records of A. femoratus from MO and southeastern ND. These are female records however, which calls into question their validity, but still it is possible that A. femoratus occurs in the Tallgrass Prairie region and Midwest. Because of the difficulty in separating the females, records of A. femoratus in the Tallgrass Prairie region and Midwest should be based on males—see male key. (1)
 A. splendens --- Thorax, pronotum: with dorso-ventral ridge and dorso-lateral angle blunted, not sharply edged or pointed, the dorso-lateral angle oblique and not forming a distinct right angle in dorsal view - - Wings: slightly darkened - - Nesting habitat: sand (1)
Females, A. texanus VERSUS A. sericeus and A. splendens -- Modified from Mike Arduser Key
 A. sericeus and A. splendens --- Thorax, scutum: densely pitted, rugoso-pitted or weakly reticulate, but not doubly pitted - - Thorax, pronotum: with dorso-ventral ridge and dorso-lateral angle variable - - Wings: color variable (2)
 A. texanus --- Thorax, scutum and scutellum: doubly pitted, i.e. with uniformly scattered large pits on a more finely, densely pitted background, but note that this is a variable character as both the larger pits and smaller finer pits vary in density and coarseness - - Thorax, pronotum: with dorso-ventral ridge and dorso-lateral angle relatively sharp and right-angled - - Wings: not darkened, mostly clear - - NOTE: A. texanus is very similar to the western species A. angelicus, and the two are sympatric at the eastern edge of the Great Plains. They can usually be separated by the micropitting and microsculpturing on the shoulders of T1, which are dense and dull in A. texanus but slightly sparser and shinier in A. angelicus. In addition, the wings are SLIGHTLY cloudy in A. texanus but very clear in A. angelicus. (1)
Females, abdomen, tergites -- Modified from Mike Arduser Key
 A. melliventris and A. virescens --- blackish or amber, not metallic green (3)
 A. sericeus, A. splendens, and A. texanus --- metallic green, like thorax (3)
Male, A. angelicus vs. A. texanus
 A. angelicus - Hind tibia with black to brown markings on the surface facing the abdomen and never markings on the opposite surface (1)
 A. texanus - Hind tibia with black to brown markings on both surfaces, OR if lacking on the surface facing the abdomen then also lacking on the opposite side, OR sometimes present on the outer surface even if lacking on the inner surface (1)
Male, A. angelicus, A. sericeus, A. splendens, A. texanus - Combination of characters - A difficult and subtle group to separate correctly, particularly without experience
 A. angelicus and A. texanus - Leg, basitarsus, Both these indistinguishable species also have a basitarsal ridge similar to A. splendens, but it is entirely the same color as the tibia and always well hidden in the surrounding hairs, it ends in a sharp angle, it is usually extremely difficult to detect except by those with experience, see A. splendens section for where to look - -Thorax, propodeal triangle, area is a network of cells created by raised lines, these lines less prominent in comparison to the other species and also less uniformly distributed, they are large in the center and gradually get smaller towards the sides and then disappear into the general surface roughness on the sides of the triangle, in comparison, the cell size is smaller, experienced users can often detect a small triangular center section of the propodeal triangle that is a SLIGHTLY darker green and often having a SLIGHTLY different pattern of raised lines - - Wings are clear or with only a very faint hint of brown - -Occurs in all habitats - See detailed character on telling A. sericeus males from males of A. texanus (2)
 A. sericeus - Leg, basitarsal ridge is usually absent, if it is present, it has only a vague rounded end and is the same color as the surrounding segment - Thorax, propodeal triangle area, composed of network of cells created by prominent raised lines, these cells uniformly distributed throughout the whole triangle, in comparison, the cell size averages larger than the others - -Experienced users will NOT detect a small, different-colored triangular center section of the propodeal triangle, the entire area uniformly colored and patterned - Wings are clear or with only a very faint hint of brown - -Occurs in all habitats - See detailed character on telling male A. sericeus from A. texanus elsewhere in guide (1)
 A. splendens - Leg, tibia, basitarsus, UNIQUE among the 4 in that it has a ridge that runs from the tibia end of the basitarsus about half-way down, the tip of the ridge is clearly amber-brown colored, this colored end not hidden by the surrounding hairs, this ridge can still be hard to find, to see turn the specimen upside down and look for it on the side of the basitarsus that faces the abdomen, this is the side with the densest hair, Also UNIQUE among these species in that it has a small horseshoe-shaped amber colored raised spot at the apical end of the rear basitarsus, if you follow the imaginary line of the ridge it will take you right to this feature - - Thorax, propodeal triangle, area composed of cells created by raised lines, these lines as prominent as in A. sericeus but the interior of the cells about ONE, or only a little bit more than one, width of the individual lines wide , Experienced users can often detect a small triangular center section of the propodeal triangle that is a SLIGHTLY darker green and often having a SLIGHTLY different pattern of raised (1)
Male, A. coloradinus vs A. virescens
 A. coloradinus - Usually less common - - Leg, hind, femur, inner side, brown markings form a broad stripe along entire segment - Hair, In direct comparison larger, sternites with a greater density and length of hairs- - S2-3 with no or only restricted pale markings, tergite pale markings tending towards cream colored (1)
 A. virescens - Usually more common - - Leg, hind, femur, inner side, brown markings located only as large patches at apical and basal ends - In direct comparison smaller, sternites with sparser and shorter hairs- - S2-3 clearly with pale markings, though not making up the majority of the segment, tergite pale markings tending towards yellow colored (1)
Male, A. femoratus, A. obliquus, A. texanus and A. angelicus
 A. texanus and A. angelicus - Hind femur not as greatly swollen, width less than HALF the length - Ridge on basitarsus so inconspicuous that it is usually impossible to detect and never rises above the surrounding hairs - Apical groove on basistarsus not present - S5-6 LESS THAN 50 percent yellow (2)
 A. femoratus - Femur greatly swollen, width GREATER than half the length - UNIQUE in having the ridge at the base of the underside of the basitarsus PROMINENT clearly rising above the surrounding hairs - Apical groove on the underside of the basitarsus is CLEARLY PRESENT and ends in an amber colored tip - S5-6 greater than 50 percent yellow (1)
 A. obliquus - Hind femur very swollen, but less so than A. femorata, width about EQUAL to half the length - Ridge on basitarsus so inconspicuous that it is usually impossible to detect and never rises above the surrounding hairs - Apical groove on basistarsus not present - S5-6 greater than 50 percent yellow (1)
Male, A. nasutus vs. all others, head, clypeus, size
 All others - Clypeus slightly broader than long to 2x as broad as long, appearing smoothly convex when viewed head-on and at most with a small apical ridge which does not appear broadly flattened at its apex (14)
 A. nasutus - Clypeus 3x broader than long and apically truncated such that the rim appears broadly flat and smooth when viewed from below (1)
Male, A. sericeus vs A. texanus
 A. sericeus - T2-4 has scattered thin, dark hairs that emerge from the dark latitudinal integument bands and lay prone across the narrow transparent rims of these segments, but are not noticeable except under magnfication - In direct comparison, the dark latitudinal bands of the tergites have no or only vague green overtones (1)
 A. texanus - T2-4 has scattered thin and white or pale hairs that emerge from the dark latitudinal integument bands and lay prone across the narrow transparent rims of these segments, but are not noticeable except under magnfication, - In direct comparison, the dark latitudinal bands of the tergites have a STRONG metallic green to blue overtone (1)
Male, A. texanus vs A. virescens
 A. texanus - With a decent scope and good lighting you should be able to see 3-5 enlarged hairs on the apical margin of S4 - There should be a ridge running about one-third to one-half way along the underside of the basitarsus although it may be hidden by dense hairs, this ridge often looks like a shark fin (1)
 A. virescens - WITHOUT 3-5 enlarged hairs on the apical margin of S4 - WITHOUT a ridge on the underside of the basitarsis, while hairs are present along the underside margin of the basitarsis they do not obsure the margin and no shark fin like ridge present (1)
Male, T4, form of the dark integumental latitudinal band near the rim, be sure to examine tergite from multiple angles under sufficient lighting
 ONLY apical rim with latitudinal band that extends up the lateral sides of tergite - Dark latitudinal band covering about 1/2 the longitudinal length of the tergite, not including the portion of the rim that may be pale and transparent (9)
 ONLY apical rim with latitudinal band that extends up the lateral sides of tergite - Dark latitudinal band comprises 1/4 the longitudinal length of the tergite, not including the portion of the rim that may be pale and transparent (5)
 BOTH apical and basal rims with dark latitudinal bands that extend on the lateral sides of the tergite such that the tergite appears largely black with a YELLOW band INSIDE this blackness, sometimes the basal band is hidden by the proceeding tergite or covered in dense, white hairs (4)
 ONLY apical rim with latitudinal band NOT extending up the lateral sides of the tergite although on the sides there are dark patches basally - Dark latitudinal band comprises 1/4 the longitudinal length or less of the tergite, not including the portion of the rim that may be pale and transparent (2)
 With strong metallic reflections, most often appearing bluish-green under lighting at certain angles, and a basal dark integumental band, in addition to the near-apical dark integumental band, which is often hidden beneath the rim of T3 (2)
Male, abdomen, S4, specialized hairs - These hairs or setae are longer and thicker than other hairs on the sternites, at times they are darker colored, but not necessarily so and thus you must inspect the segment closely, which is often impossible when the abdomen is curled
 2 to 4 thick hairs on towards the sides of the rim or margin of the segment (9)
 No enlarged hairs present (9)
 14-20 enlarged evenly spaced hairs along the rim or margin (1)
Male, abdomen, S4, surface
 S4 not flat, with latitudinal shallow swollen areas or mounds, usually towards the rim (14)
 S4 completely flat without swollen areas (6)
Male, abdomen, T1, surface facing propodeum, color - Note that this surface can be hidden if the abdomen is tight against the propodeum
 Dark (16)
 Light (3)
Male, abdomen, sternum, color pattern
 S5 and S6 with some light to yellow markings, these markings may be extensive or minimal and are usually found either near the base or the apex of the sternite - S1-S4 with extensive yellow markings (13)
 S5 and S6 entirely dark-colored with the possible exception of scattered yellow hairs - If yellow markings are present on S1-S4 they are minimal and found at the base of the sternites (3)
Male, hind leg, basitarsus, groove or trough present on the underside of the basitarsus, often ending in a spoon-shaped point just prior to the end of the basitarsus where it joins the tarsal segments, the groove is in the same plane as the ridge, if present, and the tibial spurs
 Without apical groove (13)
 Apical groove present - Note that the end of the groove is often dark colored (3)
Male, hind leg, femur, side FACING the abdomen, presence and patterns of dark markings
 Only on the end nearest the tibia, can be extensive but does not create a complete stripe from one end to the other (10)
 A complete stripe extending from coxa to tibia (6)
 On both ends of the femur, but does not form a complete stripe - Often the base of the femur is hard to see, in that case do not use character (6)
 No markings other than minute amounts at the joints (2)
 Only on the end nearest the trochanter, can be extensive but does not create a complete stripe from one end to the other (1)
Male, hind leg, femur, size
 Relatively SLENDER - Length of Femur greater than 3 times the width (11)
 Clearly SWOLLEN to somewhat swollen - Femur length 1.5 to 3.0 times the width (9)
Male, hind leg, femur, small tooth on the underside about one fifth of the way to the end with the tibia - Careful, can be hard to see when the legs are folded
 With tooth (9)
 Without tooth (6)
Male, hind leg, tibia, side FACING the abdomen, presence and patterns of dark color markings
 Mark covering less than three quarters of the length of the tibia, often much less (9)
 No markings except for tiny amounts near the joints (9)
 Complete stripe extending from femur to basitarsus - At times may not quite be complete but, covering more than three quarters the length of the tibia (5)
Male, hind leg, trochanter, color
 Mostly to all dark brown or metallic green, less than half may be yellow (11)
 Mostly to all yellow, less than one third may have metallic green to dark brown (7)
Male, hind leg, underside of basitarsus, in the region between where the two tibial spurs bracket the basal portion of the basitarsus
 No ridge present, integument uninterrupted and smooth (13)
 With a ridge originating at the base and running about one third to one half way along the basitarsus, note this ridge is often difficult to see as it can be hidden by hairs, the size and shape can be species specific (6)
Males, A. fasciatus vs. A. melliventris - Note, A. fasciatus has been recently resurrected as a species
 A. fasciatus - Legs, trochanters, entirely yellow (1)
 A. melliventris - Legs, trochanters, metallic green (1)
Males, A. femoratus VERSUS A. melliventris and A. sericeus -- Modified from Mike Arduser Key
 A. melliventris and A. sericeus --- Legs, hind, femur: swollen or not, IF swollen then its length at least 3x its maximum width - - Legs, hind, femur: with or without a ventro-apical tooth - - Legs, hind, basitarsus: without a ventro-basal keel or carina (3)
 A. femoratus --- Legs, hind, femur: greatly swollen like a balloon, its length and maximum width equal or nearly so - - Legs, hind, femur: with a sharp tooth or angulate process ventro-apically - - Legs, hind, basitarsus: with a ventro-basal keel or carina - - Wings, membranes: clear (1)
Males, A. melliventris VERSUS A. sericeus -- Modified from Mike Arduser Key
 A. melliventris --- Legs, hind, femur: not swollen, and little if any larger than mid femur - - Legs, hind, femur, ventral margin: entirely simple, without a small spicule or spur subapically - - Abdomen, T1: usually light basally, yellow to amber - - Abdomen, tergites: with yellow bands wider than brownish bands - - NOTE: A. fasciatus, a former synonym of A. melliventris, has recently been recognized as a separate species. The two can usually be separated by the color of the trochanters, which are all yellowish in A. melliventris but metallic green in A. fasciatus. (2)
 A. sericeus --- Legs, hind, femur: somewhat swollen, about 3x as long as broad, and larger than mid femur - - Legs, hind, femur, ventral margin: with a small distinct spicule or spur subapically - - Abdomen, T1: usually dark basally - - Abdomen, tergites: with black bands as wide or wider than yellow bands - - NOTE: despite being quite different from each other based on genitalia, A. sericeus is otherwise very similar to A. texanus. However, the two can be separated based on the hind femur. The small spicule on the ventral surface of the hind femur in A. sericeus usually projects perpendicularly from the surface of the femur, while in A. texanus the spicule is more toothlike, somewhat flattened, and projects at an angle from the surface of the femur. The surface of the femur distal to the spicule is somewhat concave in A. texanus, but entire in A. sericeus. (1)
Males, A. splendens VERSUS A. texanus -- Modified from Mike Arduser Key
 A. splendens --- Legs, hind, basitarsus, inner basal margin: with a darkened, linear callus or sclerotized ridge - - Legs, hind, femur: relatively swollen, its LxW ratio about 2 to 1 - - Legs, hind, femur, spicule or spur ventrally near apex: very minute, occasionally absent - - Genitalia, gonostylus, inner lobe: crescentic, not rounded or triangular - - Nesting habitat: sand (1)
 A. texanus --- Legs, hind, basitarsus, inner basal margin: without a darkened, linear callus or sclerotized ridge - - Legs, hind, femur: not as swollen, its LxW ratio about 2.5 to 1 or greater - - Legs, hind, femur, spicule or spur ventrally near apex: small, but larger than that of A. splendens - - Genitalia, gonostylus, inner lobe: rounded to broadly subtriangular, not crescentic - - Nesting habitat: various - - NOTE: A. texanus is very similar to the western species A. angelicus, and the two are sympatric at the eastern edge of the Great Plains. Compared to A. texanus, the hind femur of A. angelicus is usually slightly less swollen, the LxW ratio being about 3 to 1, and the inner lobe of the gonostylus in A. angelicus is reduced to a more triangular shape rather than a broad lobe. Additionally, the base of the gonostylus is more inflated. (1)
Males, A. virescens VERSUS A. femoratus, A. melliventris, A. sericeus, A. splendens, and A. texanus -- Modified from Mike Arduser Key
 › A. femoratus, A. melliventris, A. sericeus, A. splendens, and A. texanus --- Abdomen, S4: with a low, transverse swelling along the apical or preapical margin, but note this feature is often easy to overlook, best seen in oblique lateral view - - Abdomen, S5-S6: usually yellow in part - - Legs, hind, femur: size variable but often conspicuously larger than mid femur, appearing inflated, its length about 3x its maximum width or less - - Genitalia, gonostylus: shape variable, apical stylus may or may not be present (6)
 A. virescens --- Abdomen, S4: entirely flat, WITHOUT a low, transverse swelling along the apical or preapical margin - - Abdomen, S5-S6: USUALLY all dark brown to black, without any yellow maculations - - Legs, hind, femur: not much larger than mid femur, e.g. about 4x as long as broad, and usually lacking a dark stripe on posterior surface - - Genitalia, gonostylus: terminating in an apical stylus - - NOTE: a similar species to A. virescens is A. coloradinus, a Great Plains species which may overlap in range with A. virescens. Although similar to A. virescens, A. coloradinus is slightly larger, and the dark stripe on the posterior surface of the hind femur is PRESENT. Also, the inner gonostylar flap of A. coloradinus LACKS a pronounced, medially-directed process at its base, which is PRESENT in A. virescens. (1)
Males, genitalia, gonostylus -- Modified from Mike Arduser Key
 A. femoratus, A. melliventris, and A. sericeus --- broad, flap-like, lacking an apical stylus directed medially (4)
 A. splendens and A. texanus --- with an apical stylus directed more-or-less medially (2)
Sex; number of antennal segments
 Female; 12 (15)
 Male; 13 (15)
State or province where bee was collected
 TX (22)
 NM (20)
 WY (20)
 CO (18)
 AZ (16)
 KS (16)
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 NE (16)
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 UT (16)
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 Manitoba (11)
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 British Columbia (8)
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 IN (8)
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 MA (8)
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 ME (8)
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 NJ (8)
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 NY (8)
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 Ontario (8)
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 WI (8)
 WV (8)
 Alberta (7)
 AL (6)
 FL (6)
 MS (6)
 New Brunswick (2)
 Nova Scotia (2)
 Saskatchewan (2)
Subgenus
 Agapostemon (27)
 Notagapostemon (2)