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1.
Ticks Tick Borne Dis ; 13(3): 101924, 2022 05.
Article in English | MEDLINE | ID: mdl-35217334

ABSTRACT

Tortoise ticks, Hyalomma aegyptium, are considered so strongly associated with their hosts that they are even used as indirect indicators for them. In such a case, a robust pattern of congruence between host and parasite could be expected, with phylogeographic breaks within the host being reflected in their parasites. We sequenced two mitochondrial partial gene regions (12S rRNA and Cytochrome Oxidase 1) from ticks across northern Africa and Anatolia, and compared patterns of variation with those identified in its main host, Testudo graeca. Two distinct haplogroups were identified, both of which were found distributed across much of northern Africa. This pattern does not reflect the known variation within the host, which has multiple, geographically disjunct subspecies in this region, but rather the major climatic zones. This relationship can be explained by adaptive processes to environmental conditions influenced by the climate, as well as by the spatial structure of the communities of tick potential hosts in larval and nymphal stages. Extensive anthropogenic movement of tortoises may also obscure congruence patterns between H. aegyptium ticks and their hosts.


Subject(s)
Ixodidae , Tick Infestations , Ticks , Turtles , Animals , Ixodidae/parasitology , Nymph , Tick Infestations/epidemiology , Tick Infestations/parasitology , Tick Infestations/veterinary , Turtles/parasitology
2.
Mol Phylogenet Evol ; 161: 107152, 2021 08.
Article in English | MEDLINE | ID: mdl-33741534

ABSTRACT

Phylogenetic relationships of sub-Saharan African natricine snakes are understudied and poorly understood, which in turn has precluded analyses of the historical biogeography of the Seychelles endemic Lycognathophis seychellensis. We inferred the phylogenetic relationships of Seychelles and mainland sub-Saharan natricines by analysing a multilocus DNA sequence dataset for three mitochondrial (mt) and four nuclear (nu) genes. The mainland sub-Saharan natricines and L. seychellensis comprise a well-supported clade. Two maximally supported sets of relationships within this clade are (Limnophis,Natriciteres) and (Afronatrix,(Hydraethiops,Helophis)). The relationships of L. seychellensis with respect to these two lineages are not clearly resolved by analysing concatenated mt and nu data. Analysed separately, nu data best support a sister relationship of L. seychellensis with (Afronatrix,(Hydraethiops,Helophis)) and mt data best support a sister relationship with all mainland sub-Saharan natricines. Methods designed to cope with incomplete lineage sorting strongly favour the former hypothesis. Genetic variation among up to 33 L. seychellensis from five Seychelles islands is low. Fossil calibrated divergence time estimates support an overseas dispersal of the L. seychellensis lineage to the Seychelles from mainland Africa ca. 43-25 million years before present (Ma), rather than this taxon being a Gondwanan relic.


Subject(s)
Colubridae/genetics , Evolution, Molecular , Phylogeny , Phylogeography , Africa South of the Sahara , Animals , Sequence Analysis, DNA , Seychelles
3.
Mol Phylogenet Evol ; 155: 106969, 2021 02.
Article in English | MEDLINE | ID: mdl-33031930

ABSTRACT

Plate tectonics constitute one of the main mechanisms of biological diversification on Earth, often being associated with cladogenetic events at different phylogenetic levels, as well as with exchange of faunas and floras across previously isolated biogeographic regions. North Africa and Arabia share a complex geological history that dates back to the break-up of the Arabian plate from the African plate ~30-25 Mya, followed by various geological events, such as the formation of the Red Sea or the connection between the African, Arabian and Eurasian plates. Species with Saharo-Arabian distributions have shown a close association between their evolutionary history and these geological events. In this study, we investigate the systematics, biogeography and evolution of the genus Tropiocolotes, a group of small ground-dwelling geckos, comprised by 12 species distributed from the Atlantic coast of North Africa to southwestern Iran. Species delimitation analyses uncovered the existence of high levels of undescribed diversity, with forms here considered at the species level including Tropiocolotes tripolitanus (Mauritania and southern Morocco), T. nattereri (southern Israel) and T. scorteccii (Yemen and Oman). Phylogenetic and biogeographic analyses recovered two main clades, an exclusively African clade and a Saharo-Arabian clade, that split ~25 Mya following the vicariant event mediated by the separation of the Arabian and African plates. The complex geological activity around the Red Sea is associated with the diversification within the Saharo-Arabian clade, including the colonization of North Africa from a second Tropiocolotes group. Results also provide new insights into the geographic distribution of Tropiocolotes nubicus, previously considered as exclusively associated to the Nile River valley, extending its known distribution further west, up to the Central Mountains of the Sahara. Accordingly, the Nile River seems to act as a major biogeographic barrier, separating Tropiocolotes nubicus and T. steudneri in their western and eastern margins, respectively.


Subject(s)
Biological Evolution , Lizards/classification , Phylogeography , Africa, Northern , Animals , Bayes Theorem , Haplotypes/genetics , Likelihood Functions , Phylogeny , Species Specificity , Time Factors
4.
Folia Parasitol (Praha) ; 652018 Oct 02.
Article in English | MEDLINE | ID: mdl-30348909

ABSTRACT

Tissue samples from wildlife from South Africa were opportunistically collected and screened for haemoprotozoan parasites using nonspecific PCR primers. Samples of 127 individuals were tested, comprising over 50 different species. Haemogregarines were the most commonly identified parasites, but sarcocystids and piroplasmids were also detected. Phylogenetic analyses estimated from the 18S rDNA marker highlighted the occurrence of several novel parasite forms and the detection of parasites in novel hosts. Phylogenetic relationships, which have been recently reviewed, appear to be much more complex than previously considered. Our study highlights the high diversity of parasites circulating in wildlife in this biodiverse region, and the need for further studies to resolve taxonomic issues.


Subject(s)
Apicomplexa/isolation & purification , Biodiversity , Mammals/parasitology , Reptiles/parasitology , Animals , Apicomplexa/classification , DNA, Protozoan/analysis , Host-Parasite Interactions , Protozoan Infections, Animal/parasitology , RNA, Ribosomal, 18S/analysis , South Africa
5.
Acta Parasitol ; 58(4): 607-11, 2013 Dec.
Article in English | MEDLINE | ID: mdl-24338327

ABSTRACT

Water frogs, Pelophylax perezi, that are introduced in the Azores, were screened for parasites using PCR primers known to amplify Apicomplexa parasites, and using nematode-specific primers. With the former, three different organisms were detected: Hepatozoon, a trichodinid protozoan ciliate and a possible Stramenopile. Using the latter set of primers, a single unknown spirurid nematode was also detected. Phylogenetic analyses indicate that Hepatozoon detected within amphibian hosts appear to form a clade, although relationships of these parasites do not match the vertebrate intermediate host phylogeny. Regarding the possible Stramenopile, it is unclear whether this organism was actually present on the amphibian or in the water on the surface of the tissue sample. Our findings highlight that many different organisms can be detected with these primers and that they can be used to screen introduced host populations to detect parasites that have been brought with them.


Subject(s)
Apicomplexa/isolation & purification , Nematoda/isolation & purification , Ranidae/parasitology , Animals , Apicomplexa/classification , Apicomplexa/genetics , Azores , Cluster Analysis , DNA Primers/genetics , Molecular Sequence Data , Nematoda/classification , Nematoda/genetics , Phylogeny , Polymerase Chain Reaction/methods , Sequence Analysis, DNA
6.
Mol Phylogenet Evol ; 67(3): 615-20, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23435267

ABSTRACT

Lizards of the genus Trachylepis are a species-rich group of skinks mainly inhabiting Africa, Madagascar, and several other islands in the western Indian Ocean. All except one probably introduced species of Madagascan Trachylepis are endemic. Two species groups have been distinguished on the basis of subocular scale shape but their phylogenetic relationships remained unclear. We inferred a multilocus phylogeny of the Madagascan Trachylepis species, based on a concatenated dataset of 3261 bp from 3 mitochondrial and 4 nuclear genes with a dense Madagascan taxon sampling and find high support for the monophyly of the endemic Madagascan Trachylepis. The two species groups in Madagascar are highly supported as clades. The highland species T. boettgeri is nested in the T. aureopunctata species group of mainly arid-adapted species, suggesting a colonization of highland swamps by ancestors inhabiting dry western Madagascar. The Seychellois species were sister to the T. maculilabris/T. comorensis clade, suggesting their origin directly out of Africa as with Seychellois chameleons. In Madagascar, a high intraspecific molecular variation was confirmed for T. gravenhorstii, T. elegans, and T. vato, indicating a need for taxonomic revision.


Subject(s)
Lizards/classification , Lizards/genetics , Phylogeny , Africa , Animals , DNA, Mitochondrial , Genetic Variation , Molecular Sequence Data
7.
Mol Phylogenet Evol ; 54(2): 634-9, 2010 Feb.
Article in English | MEDLINE | ID: mdl-19850142

ABSTRACT

We analyse for the first time the genetic diversity within Ptyodactylus oudrii across the Maghreb. Two mitochondrial (12s rRNA and 16s rRNA) and two nuclear (C-mos and ACM4) markers are used. The results confirm the specific status of P. oudrii and show high levels of intraspecific variability, indicative of species complex. Lineages found are geographically concordant, and show similar patterns to that found in other species from the region. The study highlights once more the importance of the region as a source of genetic diversity.


Subject(s)
Genetic Variation , Genetics, Population , Lizards/genetics , Phylogeny , Africa, Northern , Animals , Bayes Theorem , Cell Nucleus/genetics , DNA, Mitochondrial/genetics , Evolution, Molecular , Geography , Haplotypes , Lizards/classification , Sequence Alignment , Sequence Analysis, DNA , Species Specificity
8.
Trends Ecol Evol ; 20(1): 6-7; author reply 8-9, 2005 Jan.
Article in English | MEDLINE | ID: mdl-16701332
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