Molecular diversification of Trichuris spp. from Sigmodontinae (Cricetidae) rodents from Argentina based on mitochondrial DNA sequences

Abstract

A molecular phylogenetic hypothesis is presented for the genus Trichuris based on sequence data from mitochondrial cytochrome c oxidase 1 (cox1) and cytochrome b (cob). The taxa consisted of nine populations of whipworm from five species of Sigmodontinae rodents from Argentina. Bayesian Inference, Maximum Parsimony, and Maximum Likelihood methods were used to infer phylogenies for each gene separately but also for the combined mitochondrial data and the combined mitochondrial and nuclear dataset. Phylogenetic results based on cox1 and cob mitochondrial DNA (mtDNA) revealed three clades strongly resolved corresponding to three different species (Trichuris navonae, Trichuris bainae, and Trichuris pardinasi) showing phylogeographic variation, but relationships among Trichuris species were poorly resolved. Phylogenetic reconstruction based on concatenated sequences had greater phylogenetic resolution for delimiting species and populations intra-specific of Trichuris than those based on partitioned genes. Thus, populations of T. bainae and T. pardinasi could be affected by geographical factors and co-divergence parasite-host.

Morphobiological analysis of Trichuris vulpis (Nematoda, Trichuridae), obtained from domestic dogs

“…The embryonic life stages of parasites develop in the environment (Hasegawa & Dewi, 2017;Xie et al, 2018;Eo et al, 2019). Currently, there are almost 80 species in the genus Trichuris, and most of them are parasites of specific host taxa (Callejón et al, 2016). Researchers in many countries are interested in this parasitic group because of the danger it poses to humans.…”

First report of molecular characterization and phylogeny of Trichuris fossor Hall, 1916 (Nematoda: Trichuridae)

“…Nematodes of the genus Trichuris (Roederer, 1761) ('whipworms') inhabit the ceca of a wide variety of mammalian hosts worldwide (Callejón et al, 2015;Robles et al, 2018). Approximately 80 species are described based mostly on reports that have used biometrics, morphological features, host(s) infected, and/or geography (Guardone et al, 2013;Doležalová et al, 2015;Callejón et al, 2016).…”

“…Approximately 80 species are described based mostly on reports that have used biometrics, morphological features, host(s) infected, and/or geography (Guardone et al, 2013;Doležalová et al, 2015;Callejón et al, 2016). These characteristics are not reliable in all instances -many species have similar attributes with overlapping ranges of measurements (Callejón et al, 2015(Callejón et al, , 2016Vejl et al, 2017) and host preference may be more variable than previously thought (Doležalová et al, 2015). Approximately 24 species been reported from rodents, many of which exhibit comparable morphological patterns Doležalová et al, 2015;Eberhardt et al, 2019).…”

“…Understanding the diversity and phylogeny of whipworms is important; false classification limits our acuity of biogeography and conceals the zoonotic potential of trichurids (Callejón et al, 2015;Doležalová et al, 2015). Certain species, e.g.…”

“…A more comprehensive understanding of relationships within this group would enable predictions about how close relatives interact with their host(s). Relationships within Trichuridae have not been well resolved using genetic approaches; results differ depending on the gene(s) sequenced and the approach used for phylogenetic reconstructions (Callejón et al, 2015). Mitochondrial data, primarily cox1, have been commonly used and have allowed for high resolution of closely related lineages; however, it may be less credible to use with Trichuris species due to the degree of hybridization and maternal mitochondrial heredity seen in this genus (Callejón et al, 2015;Doležalová et al, 2015).…”