2025/05/21 by Flávia de Oliveira Bezerra, Tammy Iwasa‐Arai, Camilla A. Santos +2 · 1 voice
Environmental Science · #Turtle Biology and Conservation #Marine Ecology and Invasive Species #Parasite Biology and Host Interactions
paper · doi:10.1093/biolinnean/blaf040
Abstract Epibiosis is an interspecific association whereby one organism lives on the surface of another, called the host or basibiont. One of the many advantages of epibiosis is that the interaction with the basibiont may increase the epibiont’s dispersal capacity, especially when the basibiont are highly migratory, such as sea turtles. Such hosts are known to harbour a broad diversity of epibiont communities, and crustacean amphipods are one of the most abundant. The increase in dispersal capacity due to the epibiont habit may be a strategic adaptation for amphipods, which are direct-developmental organisms. To understand the role of sea turtles on the dispersal of their epibionts, we combined mitochondrial (Cytb) and nuclear (ITS-1) markers to assess population genetic structure and evolutionary history of the amphipod species (Podocerus chelonophilus, Hyachelia tortugae and Hyachelia lowryi) known as obligate commensals of sea turtles. We obtained amphipod specimens from 33 sea turtles of three distinct species: loggerhead (Caretta caretta), green (Chelonia mydas), and hawksbill (Eretmochelys imbricata) sampled in six localities along the Brazilian coast. Our results show high genetic diversity, low genetic structure, and high gene flow among the different turtle species and localities for all epibiont species. Our findings suggest an overlap between the life histories of the hosts and their epibionts and a probable colonization event of a small number of mitochondrial DNA lineages, leading to high gene flow over long distances promoted by historical and present interaction with the host sea turtles.