Comparative Early Life Stage Toxicity of the African Clawed Frog, Xenopus laevis Following Exposure to Selected Herbicide Formulations Applied to Eradicate Alien Plants in South Africa

SummaryThis study determined the diversity and seasonality of parasites species of the African clawed frog, Xenopus laevis (Daudin, 1802), from three localities, namely Modjadjikloof, Mokopane and University of Limpopo, Limpopo Province, South Africa. A total of seven parasite species were collected and identified. They included two nematodes, Camallanus kaapstaadiSouthwell & Kirshner, 1937 and Batrachocamallanus slomei (Southwell & Kirshner, 1937), a monogenean, Protopolystoma xenopodis (Price, 1943), a cestode, Cephalochlamys namaquensis (Cohn, 1906), a protozoan, Trichodina xenopodosFantham, 1924, two digeneans, Progonimodiscus doyeri Ortlepp, 1926 and Dollfuschella rodhainiVercammen-Grandjean, 1960. The most common and abundant parasite species by far were Cm. kaapstaadi, B. slomei and Cp. namaquensis, with Cm. kaapstaadi, B. slomei present in all localities. Trichodina xenopodos was a rare species, only present in host populations from Modjadjiskloof. Modjadjiskloof had the highest species richness (all seven parasite species) followed by Mokopane (five parasite species) and University of Limpopo (3 parasite species). There were also higher infection levels (prevalence and mean intensity) of Cm. kaapstaadi, B. slomei, Cp. namaquensis and Pt. xenopodis in hosts from Modjadjiskloof while Pd. doyeri and D. rodhaini infection levels were greater in Mokopane. The variability between localities shows that parasites with heteroxenous life cycles are more strongly associated with more pristine habitats. The variability in calculated indices (prevalence and mean intensity) also suggests that the occurrence of some of the parasites is affected by season, favouring higher infection rates during summer. This suggests that temperature has a direct role in the reproductive and developmental processes of these parasites. Neither length nor sex had an influence on the prevalence or intensity of parasites.

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Unequal contribution of native South African phylogeographic lineages to the invasion of the African clawed frog,Xenopus laevis, in Europe

PeerJ ◽

10.7717/peerj.1659 ◽

2016 ◽

Vol 4 ◽

pp. e1659 ◽

Cited By ~ 12

Author(s):

Charlotte De Busschere ◽

Julien Courant ◽

Anthony Herrel ◽

Rui Rebelo ◽

Dennis Rödder ◽

...

Keyword(s):

South Africa ◽

Xenopus Laevis ◽

South African ◽

Nuclear Dna ◽

Phylogeographic Structure ◽

Western Cape ◽

The South ◽

African Clawed Frog ◽

Northern Regions ◽

Clawed Frog

Due to both deliberate and accidental introductions, invasive African Clawed Frog (Xenopus laevis) populations have become established worldwide. In this study, we investigate the geographic origins of invasiveX. laevispopulations in France and Portugal using the phylogeographic structure ofX. laevisin its native South African range. In total, 80 individuals from the whole area known to be invaded in France and Portugal were analysed for two mitochondrial and three nuclear genes, allowing a comparison with 185 specimens from the native range. Our results show that native phylogeographic lineages have contributed differently to invasive EuropeanX. laevispopulations. In Portugal, genetic and historical data suggest a single colonization event involving a small number of individuals from the south-western Cape region in South Africa. In contrast, French invasiveX. laevisencompass two distinct native phylogeographic lineages, i.e., one from the south-western Cape region and one from the northern regions of South Africa. The FrenchX. laevispopulation is the first example of aX. laevisinvasion involving multiple lineages. Moreover, the lack of population structure based on nuclear DNA suggests a potential role for admixture within the invasive French population.

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