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bioRxiv · 10.1101/2021.10.21.465306

Widespread anthropogenic translocation of the African Clawed Frog across its native range is revealed by its co-introduced monogenean parasite in a co-phylogeographic approach

Abstract

O_LIThe management of bio-invasions relies upon the development of methods to trace their origin and expansion. Co-introduced parasites, especially monogenean flatworms, are ideal tags for the movement of their hosts due to their short generations, direct life cycles and host specificity. However, they are yet to be applied to trace the intraspecific movement of host lineages in their native ranges. C_LIO_LIAs proof of this concept, we conducted a comparative phylogeographic analysis based upon two mitochondrial markers of a globally invasive frog Xenopus laevis and its monogenean parasite Protopolystoma xenopodis in its native range in southern Africa and invasive range in Europe. C_LIO_LITranslocation of lineages was largely masked in the frogs phylogeography. However, incongruent links between host and parasite phylogeography indicated host switches from one host lineage to another after these were brought into contact in the native range. Thus, past translocation of host lineages is revealed by the invasion success of its co-introduced parasite lineage. C_LIO_LIThis study demonstrates that parasite data can serve as an independent line of evidence in invasion biology, also on the intraspecific level, shedding light on previously undetected invasion dynamics. Based upon the distribution of these invasive parasite lineages, we infer that there is widespread anthropogenic translocation of this frog, not only via official export routes, but also facilitated by the frogs use as live bait by angling communities. C_LIO_LISynthesis and applications. Data from co-introduced, host-specific parasites, as tags for translocation, can add value to investigations in invasion biology and conservation. A better understanding of the translocation history and resulting genetic mixing of host and parasite lineages in the native range can shed light on the genetic make-up of parasite assemblages co-introduced to the invasive range. Knowledge of the intraspecific movement of different lineages of animals in their native ranges also has conservation implications, since contact between divergent lineages of hosts and parasites can facilitate host switches and altered parasite dynamics in both native and invasive populations. Therefore, we recommend the inclusion of parasite data as a more holistic approach to the invasion ecology of animals on the intraspecific level. C_LI

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Schoeman, A. L., du Preez, L. H., Kmentova, N., Vanhove, M. P. M.. 2021-10-23. Widespread anthropogenic translocation of the African Clawed Frog across its native range is revealed by its co-introduced monogenean parasite in a co-phylogeographic approach. https://doi.org/10.1101/2021.10.21.465306

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