Odontomachus

Odontomachus is a genus of ants commonly called trap-jaw ants found in the tropics and subtropics throughout the world.

Overview

Commonly known as trap-jaw ants, species in Odontomachus have a pair of large, straight mandibles capable of opening 180°. These jaws are locked in place by an internal mechanism, and can snap shut on prey or objects when sensory hairs on the inside of the mandibles are touched. The mandibles are powerful and fast, giving the ant its common name. The mandibles either kill or maim the prey, allowing the ant to bring it back to the nest. Odontomachus ants can simply lock and snap their jaws again if one bite is not enough, or to cut off bits of larger food. The mandibles also permit slow and fine movements for other tasks such as nest building and care of larvae. The ants were also observed to use their jaws as a catapult to eject intruders or fling themselves backwards to escape a threat.

The larvae of trap-jaw ants are remarkable in being ornamented with long spikes and presenting dorsal adhesive pads for fixation onto internal ant nest walls. They are carnivorous, extremely active larvae. Apparently, they undergo three larval moults before entering metamorphosis. Their larvae use substrate to spin cocoons.

Diet

Trap-jaw ants are mostly carnivorous, but also consume nectar, insect honeydew, and ripe fruit.

Speed record

Trap-jaw ants of this genus have the second-fastest moving predatory appendages within the animal kingdom, after the dracula ant (Mystrium camillae). One study of Odontomachus bauri recorded peak speeds between 126 and 230 km/h (78 and 143 mph), with the jaws closing within just 130 microseconds on average. The peak force exerted was in the order of 300 times the body weight of the ant, and acceleration of 1,000,000 m/s² or 100,000 g.

Mimicry

The jumping spider genus Enoplomischus seems to mimic this ant genus.

Distribution

Odontomachus species are found in Central and South America, Asia, Australia, and Africa.

In the United States, O. haematodus was "recorded in Alabama back in 1956, but now researchers have officially confirmed that the species has spread across the Gulf Coast, at least as far east as Pensacola, Florida." In the past, O. ruginodis was thought to be confined to the Orlando region, but Magdalena Sorger, a PhD candidate at North Carolina State University, has confirmed a record of O. ruginodis more than 100 miles north of Orlando, in Gainesville, Florida. Odontomachus relictus, however, is only found in "endangered scrub habitat on central Florida’s ancient sand ridges."

Species

References

External links

• Mississippi Entomology Museum: Pictures of worker and male O. haematodus
• Ant's super-fast bite is a built-in 'ejector seat'
• Ferocious ants bite like a bullet - BBC News, 21 August 2006. Elli Leadbeater. Retrieved 22 August 2006
• Man-trap jaws make ant fastest predator - Scotsman, 22 August 2006. John Von Radowitz. Retrieved 22 August 2006

1. Odontomachus bauri
2. Odontomachus spinifer
3. Odontomachus relictus
4. Odontomachus hastatus
5. Odontomachus clarus
6. Odontomachus brunneus
7. Odontomachus haematodus
8. Odontomachus assiniensis
9. Odontomachus ruginodis
10. Odontomachus simillimus
11. Odontomachus pseudobauri
12. Odontomachus paleomyagra
13. Odontomachus cornutus
14. Dominican amber
15. Instar
16. Hastatus
17. Ant
18. List of ants of Australia
19. O. silvestrii
20. Termite