BEE FAMILY AND GENUS ACCOUNTS

I’ve provided two tools to help you identify different genera of bees. Below there is a key of characteristics that can help you sort among genera. In addition, Appendix 2 includes a detailed list of key characteristics. Many of the characteristics require a microscope or a strong hand lens to be seen.

Key of Basic Bee Characteristics

Here are some quick ways to get at some of the most common genera using some simple characteristics:

Two submarginal cells in the fore wing . . . . . see Family Megachilidae, and Genera Hylaeus, Dufourea, Panurginus, or Perdita

Obvious pollen on the undersurface of the abdomen . . . . . see Family Megachilidae

Very large size, black or metallic . . . . . see Genus Xylocopa

Large size, black and yellow (sometimes red/orange) . . . . . see Genus Bombus

Medium to large size with conspicuously hairy, brush-like hind legs (scopae) . . . . . see Genera Melissodes, Anthophora, Peponapis, or Xylocopa

Medium-size bee with elaborate white or yellow patterns on abdomen . . . . . see Genera Anthidium, Dianthidium, or Triepeolus

Small black bee with white markings on face . . . . . see Genera Hylaeus or Ceratina; see also male Andrena or Family Halictidae

Bright metallic green or blue . . . . . see Genera Agapostemon, Osmia, or Hoplitis

Strongly heart-shaped “face” . . . . . see Genus Colletes

Wasplike, hairless . . . . . see Genera Nomada or Sphecodes

Bee found in a squash blossom . . . . . see Genus Peponapis

If you are really interested in learning to identify bees, one of the best things to do is to work with already identified specimens. You can often find these at local museums or universities. As you will know what bee you are looking at, you can see what errors you make and learn from them. It is difficult to be certain your identifications are correct without what we call a reference collection.

In the following family and genus accounts, you will find a general summary for each genus, followed by a description that provides details on how to tell the genus from other genera, similar insects that you might mistake for the genus, food resources, information on nests, and timing of flight. Appendix 1 provides a California species list. Appendix 2 provides a key to females of each genus included in the book.