Ants are characterized by long and straight mandibles that can open and close with an extreme speed when catching prey or defending itself from predator, by this specialized behavior, these ants are called “Trap Jaw Ants”. The strike of mandibles takes less than 10 milisecond (1 milisecond=0,001 second), this mechanism detonated by contact of triggers hairs on the labrum (Gonenberg, 1995). The acceleration of mandibles is correlated with the ant’s size and also muscular contraction in the head.
Trap-jaw ants belong to several subfamily; Formicinae (genus Myrmoteras), Myrmicinae (genus Daceton and Strumigenys), Ponerinae (genus Anochetus and Odontomachus).
Trap-jaw ants has a unique behavior, there are; hunting behavior, bouncing and escaped jump behavior. Trap-jaw ant will open the mandible until 1800 or more during foraging time, when the prey touched the triggers hairs on the labrum, the mandible will release an action as a reflex, then the prey can not broke away. Actually Trap-jaw ants known to be predator of other small insect.
Bouncing behavior or Retrosalience (latin, retro=backward) is an action of ants that approach the intruder, alone or as a group, then simultaneously propelled themselves backward and also intruder bounced to opposite. Usually this response only for the small sizes of intruders. This action happens that the mandible strike with an extreme speed.
How about the big sizes of intruders?, in this case, trap-jaw ants will jump as an escape action. They still use the mandibles strike for jump.
Figure 3 : Odontomachus sp. (Subfamily: Ponerinae)
Carlin, N. F. and Gladstein, D. S. 1989. The “bouncer” defense of Odontomachus ruginodis and other Odontamachinae ants (Hymenoptera: Formicidae). Psyche 96:1-19.
Gonenberg, W. 1995. The fast mandible strike in trap-jaw ant Odontomachus. J comp Physiol A 176: 391-398