The functional composition of nearshore fish communities demonstrated by trait analysis: Response to environmental gradients.

There is limited understanding on nearshore fish community functioning in relation to changing environmental gradients. To address this, we investigated the trait composition of fish communities in five regions along the Portuguese coast during 4 years. Northern regions were characterized by higher Chlorophyll-α and small-sized species with short lifespans.

DNA barcoding for species assignment: the case of Mediterranean marine fishes.

Background: DNA barcoding enhances the prospects for species-level identifications globally using a standardized and authenticated DNA-based approach. Reference libraries comprising validated DNA barcodes (COI) constitute robust datasets for testing query sequences, providing considerable utility to identify marine fish and other organisms. Here we test the feasibility of using DNA barcoding to assign species to tissue samples from fish collected in the central Mediterranean Sea, a major contributor to the European marine ichthyofaunal diversity.

A ranking system for reference libraries of DNA barcodes: application to marine fish species from Portugal.

Background: The increasing availability of reference libraries of DNA barcodes (RLDB) offers the opportunity to the screen the level of consistency in DNA barcode data among libraries, in order to detect possible disagreements generated from taxonomic uncertainty or operational shortcomings. We propose a ranking system to attribute a confidence level to species identifications associated with DNA barcode records from a RLDB. Here we apply the proposed ranking system to a newly generated RLDB for marine fish of Portugal.