Discothyrea

The three hitherto known New World species of Discothyrea and the three species described below may be separated by means of the following key:

1. Antennae nine-jointed................................................ 2

Antennae seven-jointed............................................... 3

2. Length of female 1.2 mm. Costa Rica....................... horni Menozzi

Length of female 2 mm., worker 1.5 mm. "North America".... testacea Roger

3. Clypeal lamina between the antennal bases bearing a denticle, worker 1.0 mm. British Guiana.............................. denticulata Weber

Clypeal lamina not toothed............................................ 4

4. Length of female 1.8 mm. Argentina..................... neotropica Bruch

Length of female 1.1-1.2 mm.......................................... 5

5. Ventral lamina of petiole with right posterior angle, petiole 0.19 mm. high, node of petiole more sharply angulate above, color lighter. Panama, humilis Weber

Ventral lamina of petiole with acute posterior angle, petiole 0.21 mm. high, node of petiole more rounded above, color darker. Trinidad.... icta Weber