Key to Pseudomyrmecinae Genera

AntWiki: The Ants --- Online
Jump to navigation Jump to search

These keys to genera of Pseudomyrmecinae have been modified from Ward, 1990.

The following measurements (all in mm) and indices are used in the keys.

  • HW - maximum width of head, including the eyes
  • EL - eye length: length of the compound eye, measured with the head in full-face (frontal) view
  • EW - eye width: maximum width of the compound eye, measured along the short axis in an oblique dorsolateral view of the head
  • MD5 - length of the basal margin of the mandible
  • MD9 - length of the masticatory margin of the mandible
  • OI - ocular index: EW/EL

Workers and Queens


  • Antennae 12-segmented; metabasitarsal sulcus variable, always absent in New World species => 2
  • Antennae 11-segmented; metabasitarsal sulcus present; Brazil, Guyana => Myrcidris

Pseudo4t.jpg  Metabasitarsal sulcus of Myrcidris worker.


  • Mandible nearly always with proximal tooth on basal margin (pbt in figure); eyes elongate, width two-thirds or less than length (OI 0.50-0.66); metabasitarsal sulcus lacking; southern Nearctic, Neotropical (one species introduced to Hawaii) => Pseudomyrmex

Pseudo6t.gifMandible with proximal tooth.

  • Mandible lacking proximal tooth on basal margin; eyes less elongate, width two-thirds or more than length (OI 0.67-0.95); metabasitarsal sulcus usually present; Paleotropical => Tetraponera

Pseudo7t.gifMandible lacking proximal tooth.



  • Antennae 12-segmented; posterior margin of sternum VIII emarginate; external face of aedeagus lacking cornuti => 2
  • Antennae 13-segmented; posterior margin of sternum VIII broadly convex; external face of aedeagus with cornuti; Brazil, Guyana => Myrcidris


  • Masticatory margin of mandible with 6-18 teeth or denticles (or very rarely edentate), those preceding the apical tooth often quite small and abraded; if only 6 teeth present, then species small in size (HW < 0.98); basal margin of mandible one half or less the length of the masticatory margin (MD5/MD9 < 0.56), the two converging angularly at the apicobasal tooth or corner; New World => Pseudomyrmex
  • Masticatory margin of mandible usually with 2-5 teeth, typically subequal in size; rarely with 6 teeth, in which case HW > .99; basal margin of mandible two-thirds or more the length of the masticatory margin (MD5/MD9 < 0.64), the juncture between the two angular or rounded; Old World => Tetraponera


  • Ward, P. S. 1990. The ant subfamily Pseudomyrmecinae (Hymenoptera: Formicidae): generic revision and relationship to other formicids. Syst. Entomol. 15: 449-489.