Key to Palaearctic Proceratium Species

The following 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

 * Lower mesopleura entirely inflated. Petiole and postpetiole with a posterodorsal transparent blister under the integument. Israel . . . . . Proceratium galilaeum


 * Lower mesopleura not inflated. Petiole and postpetiole without a posterodorsal transparent blister under the integument . . . . . 2

2
return to couplet #1
 * Petiole without neck and rectangular. Anterior clypeal border straight. First gastral tergite with a transparent macula close to the posterior border. Palp formula 2,2 . . . . . 3


 * Petiole convex. Anterior clypeal border medially rectangular or triangular. First gastral tergite without transparent macula. Palp formula 4,3, 3,3 or 3,2 . . . . . 4

3
return to couplet #2
 * Postpetiole very sparsely granulopunctate. TL 3.03-3.29 mm and petiolar width 0.27-0.29 mm. Tunisia, Algeria, Cyprus, Turkey and Albania . . . . . Proceratium numidicum


 * Postpetiole strongly granulopunctate TL 2.84-3.32 mm and petiolar width 0.30-0.35 mm. Japan, Taiwan . . . . . Proceratium japonicum

4
return to couplet #2
 * Propodeal suture well marked. First funicular joint about 1/2 longer than broad. Pakistan . . . . . Proceratium confinium


 * Propodeal suture absent. First funicular joint at most 1/3 longer than broad . . . . . 5

5
return to couplet #4
 * Clypeus medially strongly protruding anteriorly and rectangular . . . . . 6


 * Clypeus medially protruding anteriorly but triangular . . . . . 8

6
return to couplet #5
 * Propodeal lamellae absent. Head only weakly convex posteriorly. Integumental sculpture superficial. Malta and Sicily . . . . . Proceratium melitense


 * Propodeal lamellae well developed. Head convex posteriorly. Integumental sculpture well marked . . . . . 7

7
return to couplet #6
 * Mesosoma, petiole and postpetiole with deep sculpture. Body dark ferrugineous. Japan, Korea, Korea?, China? . . . . . Proceratium watasei


 * Mesosoma, petiole and postpetiole with superficial sculpture. Colour light brown. Italy, Croatia, Greece, Algeria, Morocco and Tunisia . . . . . Proceratium algiricum

8
return to couplet #5
 * Fore tibiae without basal spine. Second tarsomere of hind legs shorter than pretarsus. First gastral sternite protruding over the postpetiolar sternite. Japan, Korea?, China? . . . . . Proceratium itoi


 * Fore tibiae with basal spine. Second tarsomere of hind legs at least as long as the pretarsus. First gastral sternite not protruding over the postpetiolar sternite . . . . . 9

9
return to couplet #8
 * Head granulate-punctate. Petiole slightly longer than broad. Second tarsomere of hind legs about as long as the pretarsus. Japan . . . . . Proceratium morisitai


 * Head reticulate-punctate. Petiole about as broad as long. Second tarsomere of hind legs about 1/5 longer than the pretarsus. Czech Republic, Hungary, Ukraine, Yugoslavia, Italy, Romania, Bulgaria, Albania, Greece, Turkey, Spain . . . . . Proceratium melinum