No abstract

The Water Framework Directive 2000/60/EC (WFD) requires Member States of the European Union (EU) to use a pool of bioindicators, that is, Biological Quality Elements (BQEs), including fish species and each Member State shall, in fact, certify the compliance with the ecological quality goals of the WFD. The New Italian Index of the Ecological State of Fish Communities (NISECI) is the WFD-compliant index for the analysis of the fish species BQE in Italian river water bodies, both wadable and non-wadable, that are not (using WFD definitions) heavily modified or artificial. The WFD requires each index to relate the conditions found in the field to reference conditions corresponding to the absence of anthropogenic alterations or to minor anthropogenic alterations. The present study defines the logical basis on the model of refinement for the reference conditions of the metrics and submetrics of NISECI relating to the biological condition of indigenous and non-indigenous species. The model was tested on an empirical basis using data from 284 ichthyological samplings taken from river basins throughout Italy. In order to clean random errors and stochastic noise due to possible different sampling methods, the data was only collected using protocols that guarantee adequately homogeneous and reliable data of abundance (overall and by size). The developed approach provided comparable and homogeneous results throughout Italian watersheds; this allowed a standardized and robust refinement of the threshold values of the demographic parameters of NISECI. The procedure used, consistent with the spatially based reference condition and ARTICLE HISTORY

Background Barbels are ray finned cyprinid fishes of the Old-World with partially unresolved, intricate taxonomy. Within the Barbus sensu lato paraphyletic assemblage, Barbus sensu stricto is a monophyletic tetraploid lineage of Europe, northern Africa and Middle East, including two monophyletic sibling genera: Barbus and Luciobarbus. Italy, Slovenia and northern Croatia are natively inhabited by several entities of the genus Barbus, whose relationships and taxonomic ranks are still unclear. Aim of the present work is to focus on phylogeography of Italian and Slovenian barbels, with an appraisal of their current taxonomy. Results One hundred fifty specimens were collected in 78 sampling sites from 33 main watersheds, widely distributed along Italian and Slovenian ichthyogeographic districts. We amplified two mitochondrial markers, cytochrome b (cytb) and control region (D-loop), to infer a robust phylogeny for our sample and investigate on species delimitation. Our results strongly indicate all Italian and Adriatic Slovenian fluvio-lacustrine barbels to be comprised into at least three distinct species. We provide a proposal of taxonomic revision and a list of synonymies for two of them and a new description under the International Code of Zoological Nomenclature rules for the third one. Conclusions If nuclear data will confirm our findings, at least three specific entities should be acknowledged across our sampling area. Namely, the three species are (i) Barbus plebejus, in the Padano-Venetian district; (ii) Barbus tyberinus, in the Tuscany-Latium district; (iii) Barbus oscensis Rossi & Plazzi sp. nov., in the Tyrrhenian and southernmost-Adriatic parts of Apulia-Campania district. Finally, we briefly discuss the implications of such a taxonomic scenario on conservation policies.