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Small wild mammals have been used to measure the damage caused by exposure to oil-contaminated soil, including deer mice. However, the study of toxic effects of crude oil using oxidative damage biomarkers in the wild rodent Calomys laucha (Vesper mouse) is absent. This investigation aimed to evaluate the effects of acute exposure to contaminated soil with different concentrations of crude oil (0, 1, 2, 4 and 8% w/w), simulating an accidental spill, using oxidative stress biomarkers in the liver, kidneys, lungs, testes, paw muscle, and lymphocytes of C. laucha. Animals exposed to the contaminated soil showed increases in lipid peroxidation and protein carbonylation at the highest exposure concentrations in most organ homogenates analyzed and also in blood cells, but responses to total antioxidant capacity were tissue-dependent. These results showed that acute exposure to oil-contaminated soil caused oxidative damage in C. laucha and indicate these small mammals may be susceptible to suffer the impacts of such contamination in its occurrence region, threatening the species' survival., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

A multigene phylogeny including 24 Rhipicephalus species from the Afrotropical and Mediterranean regions, based on mitochondrial DNA genes (COI, 12S and 16S), was constructed based on Bayesian inference and maximum likelihood estimations. The phylogenetic reconstruction revealed 31 Rhipicephalus clades, which include the first molecular records of Rhipicephalus duttoni (Neumann), and Rhipicephalus senegalensis (Koch). Our results support the R. pulchellus, R. evertsi and R. pravus complexes as more phylogenetically close to Rhipicephalus (Boophilus) than to the remaining Rhipicephalus clades, suggesting two main monophyletic groups within the genus. Additionally, the phenotypic resembling R. sanguineus s.l. and Rhipicephalus turanicus (Pomerantsev) are here represented by nine clades, of which none of the R. turanicus assemblages appeared as distributed in the Iberian Peninsula. These results not only indicate that both species include more cryptic diversity than the already reported, but also suggest that R. turanicus distribution is less extended than previously anticipated. This analysis allowed to improve species identification by exposing cryptic species and reinforced mtDNA markers suitability for intra/inter-species clarification analyses. Incorporating new species molecular records to improve phylogenetic clarification can significantly improve ticks' identification methods which will have epidemiologic implications on public health.

Although some studies have already been performed on Rhipicephalus sanguineus (Latreille) populations, there is still much disarray around its taxonomic classification. Rhipicephalus sanguineus, which is also known as " (brown dog tick) is a three-host tick that parasitizes many vertebrates, including occasional human hosts. It presents a worldwide distribution and is a vector of zoonosis with acknowledged public health importance. In Western Europe, R. turanicus (Pomerantsev) share many phenotypic features and is genetically closely related to R. sanguineus. Additionally, as these species are sympatric, they can be easily misidentified. However, by means of a thorough morphological traits analysis, it is possible to distinguish both species, especially resorting to scanning electron microscopy. This study was conducted using stereoscopic and SEM analyses, both associated with morphometric analysis, in order to help clarify the taxonomic status of this species complex. For that purpose, specimens resembling R. sanguineus were collected from dogs of the Midwestern Iberian Peninsula. Identification was performed based on taxonomical key characteristics. The obtained results allowed the authors to agree that a great morphological variability is found within R. sanguineus-like Iberian populations. Nevertheless, R. turanicus is easily identified by morphologic analysis, especially using reference specimens, and its presence in Portugal is suggested.