Key to Stenamma species in or possible in MS and AL (from Smith 1957, DuBois 1998, and Nick Blacker [pers. comm.])

Members of this genus are somewhat rarely collected because they are more active during the late fall through early spring; a time when most collectors are in the lab trying to catch up on everything they have collected from the rest of the year. Species identification in this genus can be very difficult due to variation in color, size, number of ommatidia, and strength of sculpture.

[TL = total length (head + alitrunk + waist + gaster]

Large (TL: 2.75-4.0 mm); eye large (almost 0.2 mm in greatest diameter) and with 5-12 (usually 8-10) ommatidia in greatest diameter of eye (see figure 1 below); rugose sculpture coarse
...4
Smaller (TL: 2.3-3.5 mm); eye small (typically less than or only slightly larger than 0.1 mm in greatest diameter) with 3-6 ommatidia in greatest diameter of eye (see figure 1 below); rugose sculpture variable, weak or coarse
...2

Figure 1. comparison of eyes. The first photos shows an eye with 5-12 ommatidia in greatest diameter and the 2nd and 3rd photos show eyes with 3-6 ommatidia in greatest diameter.

2 Dorsum and sides of mesosoma with tightly woven, coarse rugose sculpture that dulls the surface, appearing punctate (especially at lower magnification); dorsum of petiole and postpetiole not usually smooth, with enough sculpture to dull the surface, side of petiole and postpetiole densely punctate; eye usually with only 3 or 4 ommatidia in greatest diameter
  Sculpture on mesosoma coarse or weak, but less dense, not dulling the interrugal surfaces, which appears shining; dorsum of petiole and postpetiole either mostly lacking sculpture or more shining; eye with 4-6 ommatidia in greatest diameter
...3
3 More slender species; body and head usually light in color, yellowish brown; eyes larger (usually at least or slightly more than 0.1 mm in longest diameter), ommatidia coarse, usually with 5 or 6 in greatest diameter of eye; thoracic sculpture weak, interrugal surfaces shining; petiolar node narrow (in profile); dorsum of postpetiole with at least some sculpture, not smooth
  Body more robust; usually dark brown; eyes smaller (less than 0.1 mm in greatest diameter), ommatidia finer, with 4-6 in greatest diameter of eye; rugose sculpture coarse (but not enough to dull interrugal surfaces); petiolar node broader (in profile); dorsum of postpetiole mostly lacking sculpture, appearing smooth
4

Rugulae or the rugulose-reticulate sculpturing of the promesonotum transverse in direction

Rugulae or the rugulose-reticulate sculpturing of the promesonotum usually longitudinal in direction

...5
5
Petiole slender, petiolar node usually subconical (as viewed from above and behind); postpetiole convex laterally, almost circular (viewed from above); propodeal spines short, but distinct; rugose sculpture on promesonotum dense
Petiolar node more robust with wider crest, almost subrectangular (instead of subconical); postpetiole also more robust, with less even constriction behind, appearing somewhat bell-shaped (instead of circular); propodeal spines long and somewhat digitiform; rugose sculpture on promesonotum more sparse and less regular