Hitchhiking through life: a review of phoresy in Uropodina mites (Parasitiformes: Mesostigmata).

Several important papers discussing phoretic dispersal in animals have appeared in recent years, but the nature and evolutionary significance of the phenomenon are still not fully understood. This article reviews the current knowledge of this behaviour in Uropodina mites, which disperse at the deutonymphal stage. We first examine the morphological and behavioural attributes of Uropodina deutonymphs involved in phoretic dispersal. We then provide a systematic review of the animals that carry Uropodina, and examine the carrier-specificity of 30 well-known species. Most species are associated with a single family of carriers, or at most, two families. The available information shows that phoretic deutonymphs of most species do not show any preference for male or female carriers. The spatial pattern of attachment of phoretic deutonymphs varies according to the identity of the carrier insect. The nature of deutonymph infestation depends on the size and morphology of both the mite and its carrier. Successful phoresy also depends on synchronisation of the life cycles of the mite and its carrier, but the temporal dynamics of phoresy remain particularly poorly studied. Phoresy has ecological and evolutionary consequences for both the Uropodina and their carriers. Future research on phoresy will benefit from studies of its evolutionary development, the reasons why beetles appear to be specially favoured as carriers, how phoretic mites affect the insect that carries them, and how the apparent global decline in insect populations is affecting their symbiotic mites. [ABSTRACT FROM AUTHOR]