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The Algerian hedgehog, Atelerix algirus, is recorded from North Africa, the Balearic, Canary and Maltese islands, and into parts of the Mediterranean coastal regions of Spain. The lack of an archeozoological record in Europe, Balearic, Maltese or Canary Islands has led several authors to postulate recent introductions by humans, but few studies actually investigated this hypothesis. We used both mitochondrial and nuclear genes to test it. To this aim, we widely sampled the Algerian hedgehog in North Africa (Algeria, Morocco and Tunisia), continental Spain (Catalonia), and Balearic and Canary islands. Our mitochondrial and nuclear data are consistent and show low genetic diversity across the geographical range of the Algerian hedgehog. Our results suggest the recent colonisation of Spain, Balearic and Canary Islands by this species (Holocene), probably mediated by humans. Several subspecies, mainly based on pelage variations, have been described either from mainland or island populations, but our data do not show any genetic discontinuity, suggesting that subspecific recognition may be unwarranted. [ABSTRACT FROM AUTHOR]

Host-parasite interaction studies across hybrid zones often focus on host genetic variation, treating parasites as homogeneous. 'Intimately' associated hosts and parasites might be expected to show similar patterns of genetic structure. In the literature, factors such as no intermediate host and no free-living stage have been proposed as 'intimacy' factors likely constraining parasites to closely follow the evolutionary history of their hosts. To test whether the whipworm, Trichuris muris, is intimately associated with its house mouse host, we studied its population genetics across the European house mouse hybrid zone ( HMHZ) which has a strong central barrier to gene flow between mouse taxa. T. muris has a direct life cycle and nonmobile free stage: if these traits constrain the parasite to an intimate association with its host we expect a geographic break in the parasite genetic structure across the HMHZ. We genotyped 205 worms from 56 localities across the HMHZ and additionally T. muris collected from sympatric woodmice ( Apodemus spp.) and allopatric murine species, using mt- COX1, ITS1-5.8S- ITS2 rDNA and 10 microsatellites. We show four haplogroups of mt- COX1 and three clear ITS1-5.8S- ITS2 clades in the HMHZ suggesting a complex demographic/phylogeographic history. Microsatellites show strong structure between groups of localities. However, no marker type shows a break across the HMHZ. Whipworms from Apodemus in the HMHZ cluster, and share mitochondrial haplotypes, with those from house mice. We conclude Trichuris should not be regarded as an 'intimate' parasite of the house mouse: while its life history might suggest intimacy, passage through alternate hosts is sufficiently common to erase signal of genetic structure associated with any particular host taxon. [ABSTRACT FROM AUTHOR]

Sex-biased parasitism is rarely investigated in relation to host tolerance and resistance, which are two defense strategies hosts can adopt when challenged by parasites. Health or fitness deteriorations in less tolerant individuals with increasing parasite burden would be faster than those in more tolerant ones. Hence, the body condition and reproductive potential of an infected individual host can be considered proxies for tolerance to parasitism. We studied Mediterranean populations of the wood mouse ( Apodemus sylvaticus) and its helminth parasites. We assessed their resistance using the phytohemagglutinin test and spleen size, and their tolerance using body condition in males and females and testes mass in males. In order to avoid spurious correlations, we took into account the phylogeographic structure of the Mediterranean wood mouse populations. We used a mixed model adapted from the animal model used in quantitative genetics. While helminth infection did not differ between the two sexes, females and males differed in their measured defenses. Females seem to invest more in immune defense with increasing risk of parasite diversity, but also appear to be potentially more tolerant of parasitic diversity. These results suggest the existence of sexual differences in resistance and tolerance, and that measurements of parasitic loads alone could be insufficient to detect any underlying sexual differences in the two strategies that have evolved in response to multiple parasitic attacks. [ABSTRACT FROM AUTHOR]

The whipworm Trichuris muris is known to be associated with various rodent species in the northern hemisphere, but the species identity of whipworm infecting rodents in the Oriental region remains largely unknown. We collected Trichuris of Muridae rodents in mainland and insular Southeast Asia between 2008 and 2015 and used molecular and morphological approaches to identify the systematic position of new specimens. We discovered two new species that were clearly distinct from T. muris , both in terms of molecular phylogenetic clustering and morphological features, with one species found in Thailand and another one in Borneo. We named the new species from Thailand as Trichuris cossoni and the species from Borneo as Trichuris arrizabalagai. Molecular phylogeny using internal transcribed spacer region (ITS1-5.8S-ITS2) showed a divergence between T. arrizabalagai n. sp., T. cossoni n. sp. and T. muris. Our findings of phylogeographically distinct Trichuris species despite some globally distributed host species requires further research into the distribution of different species, previously assumed to belong to T. muris , which has particular relevance for using these species as laboratory model organisms. Unlabelled Image • Phylogenetics on genus Trichuris are mandatory to discern between species. • Trichuris from Southeast Asian murids does not belong to Trichuris muris as previously assumed. • Two new Trichuris species were described from murid rodents in Thailand and Malaysia. • The use of Trichuris muris as a laboratory model need to pay attention on its taxonomic validity [ABSTRACT FROM AUTHOR]