Abstract:
Phoresis is the interspecific symbiotic association
in which one of two participants, the phoront, utilises
the other participant in the association (the
host) for mechanical transport. The association is
seldom obligatory although it may be a common
occurrence involving certain specific participants.
Examples include flightless arthropods such as
mites and pseudoscorpions being transported by
larger winged insects, or between small flightless
insects and larger species. The transport may be
occasional and facultative or more fixed – the main
function is to facilitate dispersal to other suitable
habitats, or to food. Well-known examples include
dung beetles (Coleoptera: Scarabaeidae) transporting
predatory mesostigmatic mites, and the
wingless ‘bee louse’, Braula coeca (Diptera: Braulidae)
and its host the honeybee, Apis mellifera
(Hymenoptera: Apidae). In the former case, the
mites are transported between dung sources
where they prey on detritus-feeding mites and fly
eggs, while, although the bee louse is an obligatory symphile in honeybee nests where it depends on
the bees and their products for food, dispersal
between colonies is dependent on absconding
bees. However, the lines between phoresis and
parasitism become somewhat blurred in cases
such as that of B. coeca and A. mellifera since most of
the association between them is actually one of
benign parasitism by the fly of the host over much
of the fly’s life-cycle and phoresis is only involved
during dispersal. And, although phoresis is
considered to occur at no cost to the host, during
the larger, parasitic, part of this association there is
obviously some (Kistner 1982).
