related to Aphomomyrmex
afer, the only other African member of the Tribe. Both ant
species are inhabitants of subspecies of the forest understorey tree Leonardoxa
africana and have been extensively studied by Doyle McKey and
colleagues - see McKey studies for
details and reference list.
P. phylax is found solely as an occupant of
domatia of the L. africana subspecies africana (ssp L4
or T4 in earlier papers), which is as very specialised myrmecophyte
apparently with an obligate mutualistic relationship with this sole
species of ant. Another ant, Cataulacus
mckeyi, also is found solely as an occupant of L. africana
africana but this ant is thought to be a parasite of the Leonardoxa-Petalomyrmex
relationship benefitting from the association with the tree but
conveying no benefit on its host.
As the host tree is found only in a limited area of
coastal rain forest in Cameroun (approximately that shown as the "area
of 2001 collections" in Map 7, the
geographical range of the ant is pretty well known - from ca 4°28'N to
2°34'N, and no further than 10°25'E.
The photomontage is of worker of this very small
species that was sent to me by Professor Doyle McKey.