Petalomyrmex phylax

An obligate ant-plant mutualist that is associated with the coastal-rainforest understory tree Leonardoxa africana africana.

Distribution
This taxon was described from Cameroon.

Biology
This ant has been the subject of numerous studies (Guame and Mckey 1999) aimed at understanding the relationships between Petalomyrmex phylax, its mutualist host plant Leonardoxa africana africana and the ant Cataulacus mckeyi.

P. phylax is able to reduce herbivory on its host plants, which in turn provides nectar and swollen, hollow internodes for ant nesting. Workers are active on the plants 24 hours a day, being particularly attentive to the plant's vulnerable young leaves. The ants are most active on the nectar-producing older leaves during the early afternoon when these leaves are producing nectar. The percentage of plants occupied by this ant species can be as high as %75. Leonardoxa africana africana produces a prostoma (a small unlignified portion of the tip of the domatia where ants create an entrance hole) with dimensions that are large enough to allow for the entry of queens of its mutualist ant partner but prevents other, larger ant species from exploiting the domatia.

Nomenclature

 *  phylax. Petalomyrmex phylax Snelling, R.R. 1979b: 5, figs. 1-7, (w.q.m.) CAMEROUN. Wheeler, G.C. & Wheeler, J. 1980: 544 (l.). See also: McKey, 1984: 81.

Additional References

 * Brouat, C., N. Garcia, C. Andary, and D. McKey. 2001. Plant lock and ant key: pairwise coevolution of an exclusion filter in an ant-plant mutualism. Proceedings of the Royal Society of London B Biological Sciences. 268:2131-2141.


 * Gaume, L. and D. McKey. 1999. An ant-plant mutualism and its host-specific parasite: activity rhythms, young leaf patrolling, and effects on herbivores of two specialist plant-ant inhabing the same mymecophyte. Oikos. 84:130-144.