1. Outermost wing veins well developed..2
Outermost wing veins poorly developed; posterior border of second submarginal cell about half the length of the first..Lasioglossum
2. Anterior margin of mesoscutum abruptly declivous; lengths of posterior borders of second and third submarginal cell together subequal to the length of the first submarginal cell; posterior border of second submarginal cell less than half the length of the first..Sphecodes
Anterior margin of mesoscutum rounded; lengths of posterior borders of second and third submarginal cell together greater than the length of the first submarginal cell..3
3. Head, thorax and sometimes abdomen bright, metallic green, blue, or purple; posterior face of propodeum completely encircled by a salient rim; hind tibiae equaling or exceeding their tarsi in length..Agapostemon
Note: these last two characters readily separate this genus from the metallic green and blue genera in the tribe Augochlorini
Head and thorax black, body not metallic; abdominal terga with apical pubescence..Halictus
