The phylogeny and life cycle of two species ofProfilicollis(Acanthocephala: Polymorphidae) in marine hosts off the Pacific coast of Chile

Abstract

AbstractResolving complex life cycles of parasites is a major goal of parasitological research. The aim of this study was to analyse the life cycle of two species of the genusProfilicollis,the taxonomy of which is still unstable and life cycles unclear. We extracted individuals ofProfilicollisfrom two species of crustaceans (intermediate hosts) and four species of seagulls (definitive hosts) from sandy-shore and estuarine habitats along the south-east Pacific coast of Chile. Mitochondrial DNA analyses showed that two species ofProfilicollisinfected intermediate hosts from segregated habitats: whileP. altmanilarvae infected exclusively molecrabs of the genusEmeritafrom fully marine habitats,P. antarcticuslarvae infected the crabHemigrapsus crenulatusfrom estuarine habitats. Moreover,P. altmanicompleted its life cycle in four seagulls,Chroicocephalus maculipennis, Leucopheus pipixcan, Larus modestusandL. dominicanus,whileP. antarcticus, on the other hand, completed its life cycle in the kelp gullL. dominicanus. Accordingly, our results show that two congeneric parasites use different and spatially segregated species as intermediate hosts, and both are capable of infecting one species of definitive hosts. As such, our analyses allow us to shed light on a complex interaction network.