Images

There are a group of bees in the genus Andrena that form a fairly distinct subgenus called Tracandrena. They are notorious for being difficult to separate out and, in particular, the males all look pretty much the same. I have created a little Excel spreadsheet that help separate out the females, if anyone is interested.

Middlesex County, Massachusetts

Andrena fulvipennis "“ A very rare species this male was captured in an old sand pit in Anne Arundel County, Maryland. This species is only found in deep, permanently sandy locations. Picture taken by Brooke Alexander.

A specialist on early spring blooming brassicas. This one was collected just a few days ago along a very urbanized and disturbed section of Indian Creek in Beltsville, Maryland. Other than an overstory of trees all the herbaceous material growing seem to be invasive plants.

Collected by Ellison Orcutt, in Caroline County Virginia this small spring Andrena is a fan girl of mustards, particularly the spring mustards that are native and occur in wooded and semi-shaded areas in the spring, often very early in the spring.

A small bee, whose female is a gatherer of pollen from native mustard plants. However, this is the male as can be told by counting the number of antennal segments (13) and by the fact that it has a bright white clypeus. Which, with very very rare exceptions is something that only male Andrena have. This is Andrena arabis.

One of many small Andrenas out in the spring in Eastern North America. This one favors the pollen of brassicas. Photoshopping by Thistle Droege, photograph by Dejen Mengis.

Here is the male of the recently posted female Andrena arabis. The male illustrates what happens periodically with some of the males of this largely brown, dark group of mining bees which is that a few of them have a yellow, or in this case and off-white, clypeus. Surely this must be some sort of sexual signal as the females almost never have these markings.

Andrena asteroides, a late season aster specialist (thus the name). This species along with a number of other Andrena specialize on this group of plants, the rest of the Genus Andrena are primarily spring flower specialists. Note the very dense pollen carrying hairs on the hind femur. Wayne Boo took this picture.

Andrena asteroides, a late season aster specialist (thus the name). This species along with a number of other Andrena specialize on this group of plants, the rest of the Genus Andrena are primarily spring flower specialists. Note the very dense pollen carrying hairs on the hind femur. Wayne Boo took this picture.

Andrena asteroides "“ A male undoubtedly caught on one of the Frost Asters in Prince George's County, Maryland. Photographed by Wayne Boo

Andrena atlantica. One of over 100 Andrena species in the Mid-Atlantic area. The male of this species does not have a positive means of being identified from A. alleghaniensis. Some needs to figure this out along with many other things. Photo by Sydney Price.

Andrena banksi, female

Andrena banksi, male

Regionally common to sometimes even abundant, this is one of the larger Andrena of the spring. It can occur in almost any habitat, gathering pollen from a wide variety of the hugely abundant pollen and nectar sources that occur in Woodlands and surrounding scrub lands.

A rather pollen riddled specimen, this uncommon (at least in Maryland) species is uniquely outfit with a long-strap like labral process...for those of you who are technically inclined.

Andrena nigrihirta, female, Isle Royale National Park, Michigan

This is picture 1 from a 12 picture series by Matt Buffington at the USDA Parastitic Hymentoptera group at the Smithsonian. Matt's group uses a system very similar to ours to photograph and stack this super tiny wasp. Perhaps one of the most spectacular of the eucoiline wasps out there, species of Acantheucoela are native to South America.

The red maple, Acer rubrum, often one of the most dominant trees in deciduous woods in the East. It blooms very early in the spring and provides pollen and nectar to the set of bees, and flower flies, that come out early.

The red maple, Acer rubrum, often one of the most dominant trees in deciduous woods in the East. It blooms very early in the spring and provides pollen and nectar to the set of bees, and flower flies, that come out early.

The red maple, Acer rubrum, often one of the most dominant trees in deciduous woods in the East. It blooms very early in the spring and provides pollen and nectar to the set of bees, and flower flies, that come out early.