Key to Afrotropical Proceratium Species

The following worker key is based on Baroni Urbani, C., de Andrade, M.L. (2003) The ant genus Proceratium in the extant and fossil record (Hymenoptera: Formicidae). Museo Regionale di Scienze Naturali, Monografie, 36, 1–492.

1

 * Gastral tergite I greatly hypertrophied posteriorly. Madagascar . . . . . Proceratium diplopyx


 * Gastral tergite I round posteriorly . . . . . 2

2
return to couplet #1
 * Clypeus protruding anteriorly and surrounding the antennal sockets. Fore tibiae with a basal spine . . . . . 3


 * Clypeus reduced, medially subconvex, not surrounding and at most as long as the antennal sockets. Fore tibiae without basal spine . . . . . 5

3
return to couplet #2
 * Propodeal sides at least with a well marked angle. Funicular joints broader than long. Head, mesosoma, petiole and postpetiole opaque. Ghana . . . . . Proceratium boltoni


 * Propodeal sides unarmed, convex in side view. Funicular joints about as broad as long. Head, mesosoma, petiole and postpetiole at least superficially shining . . . . . 4

4
return to couplet #3
 * Integumental foveae smaller. Pilosity denser and shorter. Gaster convex in side view. IGR 0.27-0.29. Mauritius . . . . . Proceratium avium


 * Integumental foveae larger. Pilosity sparser and longer. Gaster less convex in side view. IGR 0.31-0.34. Mauritius . . . . . Proceratium avioide

5
return to couplet #2
 * Frontal carinae very close to each other and posteriorly fused. Lower mesopleura flat. Integumental sculpture at most granulate . . . . . 6


 * Frontal carinae far from each other and diverging posteriorly. Lower mesopleura posteriorly inflated. Integumental sculpture granulate-foveolate . . . . . 7

6
return to couplet #5
 * Head and mesosoma with suberect hairs. Kenya . . . . . Proceratium toschii


 * Head and mesosoma without suberect hairs. Cameroon . . . . . Proceratium terroni

7
return to couplet #5
 * Integumental foveae superficial. First gastral tergite longer than 1/4 of the postpetiole. Zimbabwe . . . . . Proceratium arnoldi


 * Integumental foveae deep. First gastral tergite 1/7 or less of the length of the postpetiole . . . . . 8

8
return to couplet #7
 * Integumental foveae smaller and more superficial. Gastral sculpture more superficial. Burundi . . . . . Proceratium burundense


 * Integumental foveae larger and more marked. Gastral sculpture deeper. Cameroon . . . . . Proceratium lunatum