Current and historical genetic variability of native brown trout populations in a southern alpine ecosystem: implications for future management

The highly polymorphic taxon European brown trout (genus Salmo) has high phenotypic plasticity, displaying a complex pattern of morphological and life-history variation, contributing to taxonomic confusion. Three main mitochondrial lineages (Adriatic, Mediterranean, and marmoratus) developed during the Pleistocene climatic events in the southern Alpine ecosystem. Here, the natural distribution of native brown trout S. trutta is controversial, complicated by introductions of the Atlantic strain. By investigating museum vouchers, this study aimed to retrace the historical presence of brown trout in the southern Alpine ecosystem before the beginning of mass introductions, which occurred since the middle of the 19th century. By examining the combination of historical and current genetic variability, this study aims to depict the actual impact of introductions of the introduced strain, increasing knowledge and informing conservation strategies and future management plans. The molecular approaches selected were: (i) sequencing of the mitochondrial control region and (ii) genotyping of the nuclear gene LDH-C1*. Vouchers dated the presence of the native Adriatic strain since 1821, while current genetic variability showed the widespread signature of introgression, a consequence of several decades of introductions. Focused plans to preserve local lineages are urgently needed, including short-term solution to avoid complete pauperization of this ecosystem

Monitoring and Management of Inland Waters: Insights from the Most Inhabited Italian Region

Monitoring of freshwaters allows the detection of the impacts of multiple anthropic uses and activities on aquatic ecosystems, and an eco-sustainable management of natural resources could limit these impacts. In this work, we highlighted two main issues affecting inland waters, referring to findings from the most inhabited Italian region (Lombardy, approximately 10 M inhabitants): the first issue is lake pollution by old generation pesticides, the second is river development for hydropower. In both cases, some management strategies reducing the anthropic impacts on freshwaters were discussed: organic farming and biocontrol as an alternative to diffuse pollution by agrochemicals; environmental flows and controlled sediment flushing operations to limit the hydropower impact on rivers. Although the two mentioned issues were discussed separately in this paper, the management of water resources should be carried out in a comprehensive way, accounting for the multiple impacts affecting freshwater ecosystems, including those related to the climate changes

A rapid and reliable detection procedure of Atlantic trout introgression at the diagnostic lactate dehydrogenase chain-1 gene

The Italian-native Mediterranean brown trout (Salmo ghigii) is a seriously threatened freshwater fish, especially by anthropogenic hybridisation with the domestic strains of Atlantic origin that have been repeatedly released into the wild for angling. A PCR-restriction fragment length polymorphism (RFLP) assay of the diagnostic lactate dehydrogenase chain-1 (LDH-C1) gene sequences has been routinely applied to distinguish exotic from native brown trout lineages and detect Atlantic introgression signals in the Mediterranean wild populations. Here, we used dermal swab DNA obtained from 28 wild trout to improve laboratory procedures to genetically characterise trout samples at the LDH-C1gene through (1) a capillary electrophoresis analysis of the RFLP fragments and (2) the optimisation of a diagnostic single nucleotide polymorphism analysable through mini-sequencing approaches. The developed methods were fully consistent with those obtained through the traditional approach, but their analytical process is almost entirely automated and digitalised, thus improving result readability and accuracy in the detection of alien introgressed traces in wild Mediterranean brown trout populations

Phylogeny of European Anodontini (Bivalvia: Unionidae) with a redescription of Anodonta exulcerata

Freshwater bivalves are highly threatened and globally declining due to multiple anthropogenic impacts, making them important conservation targets. Because conservation policies and actions generally occur at the species level, accurate species identification and delimitation is critical. A recent phylogenetic study of Italian mussel populations revalidated an Anodonta species bringing the number of known European Anodontini from three to four species. The current study contributes to the clarification of the taxonomy and systematics of European Anodontini, using a combination of molecular, morphological and anatomical data, and constructs phylogenies based on complete mitogenomes. A redescription of A. exulcerata and a comparative analysis of morphological and anatomical characters with respect to the other two species of Anodonta present in the area are provided. No reliable diagnostic character has emerged from comparative analysis of the morphometric characters of 109 specimens from 16 sites across the Italian peninsula. In fact, the discriminant analysis resulted in a greater probability of correct assignment to the site of origin than to the species. This confirms the difficulties of an uncritical application of visual characters for the delimitation of species, especially for Anodontinae.This research was developed under ConBiomics: the missing approach for the conservation of freshwater bivalves project Nº NORTE-01-0145-FEDER-030286, cofinanced by COMPETE 2020, Portugal 2020 and the European Union through the ERDF - European Regional Development Fund and by FCT - Fundação para a Ciência e a Tecnologia, through national funds (UID/Multi/04423/2019). FCT also supported Manuel Lopes-Lima (SFRH/BD/115728/2016).info:eu-repo/semantics/publishedVersio

Towards ecological flows: status of the benthic macroinvertebrate community during summer low-flow periods in a regulated lowland river

Climate change along with the increasing exploitation of water resources exacerbates low-flow periods, causing detrimental effects on riverine communities. The main mitigation measure currently adopted to counteract hydrological alterations induced by off-stream diversion is the release of minimum flows (MFs), even if within the European Union Water Framework Directive an upgrade towards ecological flows is urgently required to achieve good ecological status (GES). In this study, we investigated the temporal evolution of the benthic macroinvertebrate community in an Italian-regulated lowland river (Ticino River) to clarify the ecological effects of summer low flows, and we evaluated the current MFs in the perspective of meeting GES standard. Biomonitoring was carried out for four consecutive years (2019-2022), in a river site immediately below a large off-stream diversion. The four study years were characterized by different streamflow patterns, thus allowing us to compare the temporal trajectories of the community under different flow conditions. Moreover, the interruption of the low-flow periods due to overflow spilled by the upstream dam gave us the opportunity to assess the effects of experimental flow peaks. Contrary to the expectation, the macroinvertebrate assemblage kept almost unvaried across the years, showing great resistance and resilience to hydrological changes. Even in extraordinarily dry 2022, the community composition varied only slightly, with a reduction of mayflies and an increase of mollusks. However, a deterioration of the ecological status below GES standard was recorded that summer, indicating the need for an upgrading of the current MFs. This upgrade would include experimental flow peaks in critical periods, which act as intermediate disturbances, enhancing community richness, diversity, and overall quality, as well as compliance with a threshold of an index specifically developed for the hydrological pressure

Operationalizing mild cognitive impairment criteria in small vessel disease: The VMCI-Tuscany Study

Introduction Mild cognitive impairment (MCI) prodromic of vascular dementia is expected to have a multidomain profile. Methods In a sample of cerebral small vessel disease (SVD) patients, we assessed MCI subtypes distributions according to different operationalization of Winblad criteria and compared the neuroimaging features of single versus multidomain MCI. We applied three MCI diagnostic scenarios in which the cutoffs for objective impairment and the number of considered neuropsychological tests varied. Results Passing from a liberal to more conservative diagnostic scenarios, of 153 patients, 5% were no longer classified as MCI, amnestic multidomain frequency decreased, and nonamnestic single domain increased. Considering neuroimaging features, severe medial temporal lobe atrophy was more frequent in multidomain compared with single domain. Discussion Operationalizing MCI criteria changes the relative frequency of MCI subtypes. Nonamnestic single domain MCI may be a previously nonrecognized type of MCI associated with SVD