A guide to their Identification in Eastern North America

Acknowledgements

This presentation has been put together by a consortium of North American bee biologists

This presentation has developed over many years and the original web picture acknowledgements were lost, if you see one of your pictures let us know and we will add your picture credit

Correspondence can be sent to Sam Droege at sdroege@usgs.gov

Format

Each Genus has an information page followed by a page of illustrations and a map of the distribution of Eastern North American species; western populations of Eastern species are shown, but the Western species are not mapped.

The number of Eastern species are listed at the top of the page

Halictidae Groups of Genera

Agapostemon – 4 species

Augochlora pura - 1

Augochlorella - 3 Augochloropsis -

3

Halictus – 6 Lasioglossum –

115 or so Sphecodes – 34

or so

Dieunomia - 3 Nomia - 2 Dufourea - 3

Agapostemon

Larger than the other bright green halictids Has a prominent raised line or carina that circles

the OUTSIDE of the rear face of the propodeum Males with alternating bands of black and yellow

on the abdomen Common in fields, much less common in urban

areas A. virescens is usually the most common and

females easy to identify because of its black abdomen (the others are green)

Males and green females take some practice to differentiate due to often subtle differences

Similar genera: Augochlora, Augochlorella, Augochloropsis

Agapostemon – 4 Biggest of the green bees

Common

Fields

Male

Female

Augochlora pura

Common, particularly in wooded regions, nests in decaying logs

Shape and color (all black) of the tip of the female’s mandibles is distinctive

Rim of S4 in the males is straight across unlike the concave or emarginate shape of S4 in Augochlorella, its most common look-alike

Clipped tip of the marginal cell is useful when processing many specimens, but Augochloropsis also has this feature

Similar genera: Augochlorella, Augochloropsis, Agapostemon

Augochlora pura – Woodlands and edges

Common, trimmed tip of marginal cell

Female

Male

Augochlorella

Usually the most common bright green bee A. aurata, the most common, but care must

be taken to pull out the other 2 species where their ranges overlap

The smallest of all the green Halictids Males have a concave S4 rim Tip of marginal cell lays directly on the rim, a

good character for sorting out the common green bees

Similar genera: Augochlora, Augochloropsis, Agapostemon

Augochlorella – In Every Field - 3

Way Abundant!

Augochloropsis Regular, but usually the least common of the bright

green bees Some species and individuals can take on distinct

blue/purple metallic overtones A. metallica is the most common, but recent genetic

analyses indicate that there is more than one species involved

The non-oval tegula is distinctive and easy to see The band of straight hairs (fimbria) fringing the rims of

the tergites is usually distinctive in most specimens, but can be very sparse in some

Tip of marginal cell is trimmed similar to Augochlora pura

Similar genera: Agapostemon, Augochlorella, Augochlora

Augochloropsis – Least Common - 3 Green Bee

Halictus Some of the most common bees, usually associated

with fields The large headed H. ligatus and its look-alike H.

poeyi have distinct projections on their lower cheeks that makes identification easy

Because H. confusus is a dull metallic green rather than black or brown it is often confused with Lasioglossum species in the Dialictus group

Told from Lasioglossum by having all of the crossveins of the submarginal cells being the same thickness and having the short, thick, white, appressed hairs that lie on the surface of the abdomen originating on the RIM of the tergites rather than from the base

Similar genera: Lasioglossum

Halictus – Every Open Place - 6

Abundant

Lasioglossum Overall the most common group of bees encountered when

using bowl traps, because they are very small they are often netted at relatively lower numbers

Many of the most common species are only 4-6mm in size All species have at least the outermost crossvein in the outer

submarginal cell thinner or weaker than the other veins; unfortunately, in males this character is much less clear

Told from Halictus by the weakened crossvein(s) of the submarginal cells and having the short, thick, white, appressed hairs that lie on the surface of the abdomen originating on the BASE of the tergites rather than from the rim, often this results in a band of white hairs emerging from UNDERNEATH the rim of the preceding segment

Some species, however, lack these appressed hairs completely This group is being revised and several species changes will be

made over the coming years Similar genera: Halictus

Lasioglossum GroupsThere are several groups within Lasioglossum that, in

the past, have, at times, been given genera status Sensu strictu – Very large, Black, one weakened

crossvein Evylaeus – Black, 2 weakened crossveins Dialictus – Blue, green, gold, 2 weakened

crossveins, identification to species often difficult Paralictus – Blue or green, parasitic, 2 weakened

crossveins Sphecodogastra – Black, Oenothera specialists,

sparse scopal hairs Hemihalictus – 2 submarginal cells

Lasioglossum - 115

Abundant, many species, everywhere, difficult id’s

You too can see weak veins – OK maybe not – In this male only the last vein is weakened and its hard to detect

Some Black Lasioglossums

Sensu Strictu Group

Evylaeus Group

Evylaeus Group

Sphecodes All species are regular but uncommon and parasitic on other

Halictid species While the females do not have pollen carrying hairs per se, their

rear legs contain a fair amount of short hair which upon very close inspection often contain small short spines along the length of the tibia

Almost all of the females are characterized by a red to orange-red abdomen, however, many males are entirely black, but can be told by heavy surface sculpturing and widely spaced antennae

None of the species have the small, thick, white, appressed hairs found in Halictus and Lasioglossum

All wing veins are the same thickness (strong) in a similar way to Halictus

Identification to species is difficult and several taxonomic issues at the species level remain unresolved

This group is being revised and several species changes will be made over the coming years

Similar genera: Lasioglossum, Halictus

Sphecodes – 34 - Lasioglossum parasite ALMOST all with red red

abdomen

Dufourea Extremely uncommon group of species in the

East The low placement of the antennae on the

face is distinctive, particularly in conjunction with the wide clypeus

Has a pre-episternal groove, which most other species lack but unfortunately is often difficult to see

Similar genera: Halictus

Dufourea - 3

Uncommon plant specialists

Dieunomia Uncommon to rare group of summer and fall species Very large, the size of bumblebees Often specialists on composites such as sunflowers

and almost always associated with sandy soils The arched basal vein so prominent in most of the

other genera of Halictids is weak to absent Males have greatly modified legs with flanges and

extensions to the normal tibia shape, consequently, often mistaken for wasps

Females have non-oval tegulae and often have scopal hairs on the underside of their abdomen in addition to those on their legs

Similar genera: Andrena, Melitta

Dieunomia - 3

Sand specialists, large uncommon, composites

Nomia Uncommon to rare group of species in the

East The mother-of-pearl band along the rims of

the tergal segments is distinctive Some males have expanded and flanged tibiae

similar to Dieunomia Similar genera: None

Nomia – Pearl Rims - 2

Southern, uncommon

Resources Species lists, Identification Guides, and Maps for genera

and species are available at:

http://www.discoverlife.org/20/q?search=Apoidea A guide to the genera of the bees of Canada is available at:

http://www.biology.ualberta.ca/bsc/ejournal/pgs_03/pgs_03.html Mitchell’s 1960’s books on the bees of the Eastern

United States is available as a series of pdf files at:http://insectmuseum.org/easternBees.php A slightly out of date guide to the identification of the

genera of ALL of North and Central America is available at:

http://www.knoxcellars.com/Merchant5/merchant.mvc?Screen=PROD&Store_Code=KCNP&Product_Code=BGNA&Category_Code=BL