Troglodyte Ants or Trap-jaw Ants in Lowveld forest

Body length 8mm.
Spotted three individuals foraging amongst leaf litter in a damp place (a damp place is presently a rare thing around here due to a severe drought). They were moving about with jaws in the 180° open position. When disturbed, they'd take cover under leaves or in cracks, peeking out with jaws only slightly open.
There are many species of Odontomachus globally, but most sources report only two in Africa: O. troglodytes and O. assiniensis. A third, Pacific Rim species, O. simillimus has repotedly been collected from Mozambique, but I don't have a specific reference for that.
Antwiki gives a genus overview here: http://www.antwiki.org/wiki/Odontomachus
and a very useful Key to Afrotropical Odontomachus speciesThere is some hype about Trap-jaw Ants. For example: http://www.berkeley.edu/news/media/releases/2006/08/21_ant.shtml
I photographed these specimens in situ, but the abovementioned key required closer examination to I isolated one specimen on white paper for clearer pics of the petiole and gaster.
The AntWiki page on the species with many high-res images is here: http://www.antwiki.org/wiki/Odontomachus_troglodytes