Cartilaginous fish are particularly vulnerable to anthropogenic stressors and environmental change because of their K-selected reproductive strategy. Accurate data from scientific surveys and landings are essential to assess conservation status and to develop robust protection and management plans. Currently available data are often incomplete or incorrect as a result of inaccurate species identifications, due to a high level of morphological stasis, especially among closely related taxa. Moreover, several diagnostic characters clearly visible in adult specimens are less evident in juveniles. Here we present results generated by the ELASMOMED Consortium, a regional network aiming to sample and DNA-barcode the Mediterranean Chondrichthyans with the ultimate goal to provide a comprehensive DNA barcode reference library. This library will support and improve the molecular taxonomy of this group and the effectiveness of management and conservation measures. We successfully barcoded 882 individuals belonging to 42 species (17 sharks, 24 batoids and one chimaera), including four endemic and several threatened ones. Morphological misidentifications were found across most orders, further confirming the need for a comprehensive DNA barcoding library as a valuable tool for the reliable identification of specimens in support of taxonomist who are reviewing current identification keys. Despite low intraspecific variation among their barcode sequences and reduced samples size, five species showed preliminary evidence of phylogeographic structure. Overall, the ELASMOMED initiative further emphasizes the key role accurate DNA barcoding libraries play in establishing reliable diagnostic species specific features in otherwise taxonomically problematic groups for biodiversity management and conservation actions.

Of the three species of the genus Squalus that occur in the Mediterranean Sea, S. blainville and S. megalops are very difficult to distinguish. This study assesses the variability in morphological features that have been used to differentiate between these species. Squalus were collected from stations within the 25-nautical mile Fisheries Management Zone around the Maltese Islands; 349 specimens were dissected and categorized into male and female, mature and immature, and individuals were randomly selected from each category to make up a sample of 169 specimens. For each individual, total length and first dorsal fin parameters were measured, and morphology of denticles isolated from the laterodorsal area, of the upper and lower teeth and of the chondrocranium was analysed. The first dorsal spine was shorter that the fin base in 93% of the specimens, which is typical of S. megalops; this character was not related to either gender or maturity. Chondrocrania with one lateral process (typical of S. blainville) and two lateral processes (typical of S. megalops) were present. Teeth from the same individuals showed morphological features that overlap between S. blainville and S. megalops. Both unicuspid (typical of S. megalops) and tricuspid denticles (typical of S. blainville) were observed on the same individuals. Twelve specimens (six having one and six having two lateral chondrocranial processes) were analysed genetically by sequencing of the mtDNA marker Cytochrome Oxidase Subunit I (COI). All resulted to be S. blainville showing that intraspecific variability in supposedly diagnostic morphological features is large enough to render these unreliable to tell apart these two species, especially in the field.

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In Malta, different sources of fuel have been used to generate electricity, including the traditional coal fired systems and the recent natural gas power station. This study will investigate the possible implications on the air and soil quality, as well as the social perception of the energy transition from heavy fuel oil (HFO) to liquified natural gas (LNG) in Malta. The implications of air pollutants emitted from power stations are well documented and whilst they may affect the local air quality due to the mobile nature of such substances, implications can be considered to be both regional and subsequently global. These pollutants may act directly on different environmental matrices since they can eventually end up in soil and water through precipitation. Understanding the public perception is important since it will help in identifying particular knowledge gaps and misinformation, as well as the willingness of the public to change the status quo on specific environmental issues. The parameters analysed for air quality were nitrogen oxides (NOx), carbon monoxide (CO), total suspended particulates (TSP) and sulfur dioxide (SO2). The results show that the oldest power station emitted high quantities of emissions when compared to the other power stations. Soil samples, from the surface and from the bottom, were collected in close proximity (within a radius of 1km to 5km) to the power stations and two control sites were sampled over a period of one-year. Two sites that were near the power stations demonstrated a high concentration of sulfates in the soil. However, a control site that was far away from the power stations depicted a higher level of sulfates. This could imply other sources of sulfates in soil other than from electricity generation. When it comes to public perception and disposition, survey results showed that the public noted and acknowledged a change in air quality over time. According to the findings, the public is aware and has been well informed with regards to the advantages related to liquified natural gas as an energy source, yet the public seems not to be aware of the advantages related to heavy fuel oil.