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Small-scale fishing plays a major role in regional economies worldwide and, with a large number of small vessels involved, it provides employment and livelihood to coastal communities. Generally recognized as more selective than other fishing practices, small-scale fishery can nevertheless be subjected to high rates of discards of both non-target species and small-sized individuals, which in turn could lead to both decreased incomes for fishers and increased depletion of fish stocks. However, if the relationship between fish size and price has long been assessed, the effect of enhanced size-selectivity of fishing gears and consequent economic gains has been little investigated. This study, set in the Porto Cesareo Marine Protected Area (Italy, Ionian Sea), aimed at testing effective strategies to improve trammel net selectivity, reducing discards and maximizing the income for fishers. Different mesh sizes (20, 22 and 24 mm) trammel nets were employed. The study consisted in 72 fishing days from July 2012 to September 2013 and each day involved experimental fishing with the three mesh sizes. A total of 16008 specimens (103 species) were collected but the analysis focused on the 18 most common species in the area for a total of 12782 individuals. Mesh size trammel nets of 20 mm and 22 mm yielded most of the biomass, 324.8 and 321.5 kg respectively, while the 24 mm mesh yielded 280.7 kg. The 24 mm mesh, even if accounted for lower income compared to the 22 mm mesh (2383.9 € vs 2590.5 €, respectively), provided significant 50% reduction of discards compared to the 20 and 22 mm mesh. The use of 24 mm mesh size was found to be an effective strategy to reduce the number of discarded organisms and, consequently, the pressure exerted on local fish stocks with associated higher revenue for fishers. The results of this study demonstrated that trammel net selectivity can improve and support conservation measures and concurrently increase profitability of local fishery

European crayfish species are a clear example of the drastic decline that freshwater species are experiencing. In particular, the native species of the Iberian Peninsula, the white clawed-crayfish (WCC) Austropotamobius pallipes, is listed as ¿endangered¿ by the IUCN and included in Annex II of the EU Habitat Directive and requires especially attention. Currently, implemented conservation management strategies require a better understanding of the genetic diversity and phylogeographic patterns, as well as of its evolutionary history. For this purpose, we have generated the largest datasets of two informative ribosomal mitochondrial DNA regions, i.e., cytochrome oxidase subunit I and 16S, from selected populations of the WCC covering its geographical distribution. These datasets allowed us to analyze in detail the (i) genetic diversity and structure of WCC populations, and (ii) divergence times for Iberian populations by testing three evolutionary scenarios with different mtDNA substitution rates (low, intermediate, and high rates). The results indicate high levels of haplotype diversity and a complex geographical structure for WCC in the Iberian Peninsula. The diversity found includes new unique haplotypes from the Iberian Peninsula and reveals that most of the WCC genetic variability is concentrated in the northern and central-eastern regions. Despite the fact that molecular dating analyses provided divergence times that were not statistically supported, the proposed scenarios were congruent with previous studies, which related the origin of these populations with paleogeographic events during the Pleistocene, which suggests an Iberian origin for these WCC. All results generated in this study, indicate that the alternative hypothesis of an introduced origin of the Iberian WCC is highly improbable. The result of this study, therefore, has allowed us to better understand of the genetic diversity, structure patterns, and evolutionary history of the WCC in the Iberian

Nematodes belonging to the genus Contracaecum (family: Anisakidae) are heteroxenous parasites with a complex life cycle. Contracaecum larvae infecting farmed fish and fishery products are economically important causing market rejection in massive infection and may have zoonotic potential. In Israel, Contracaecum larvae have been described morphologically in several fish species; however, none of these descriptions were supported by molecular tools. In 2019–2020, hybrid tilapia (Oreochromis aureus x Oreochromis niloticus) and red drum (Sciaenops ocellatus), farmed in polyculture were found to be heavily infected with nematodes referable to Contracaecum larvae. Prevalence of infection in hybrid tilapia and red drum was 53.8% and 40.9%, respectively. A combined (morphological and molecular) approach revealed that both infected fish species were parasitized by the same species of Contracaecum, although larvae in hybrid tilapia were localized in the pericardial cavity whereas in red drum, they were observed in the abdominal cavity. Genetic analysis of internal transcribed spacer rDNA and cox2 mtDNA showed high similarity to unidentified Contracaecum larvae detected in several fish species in Ethiopia, Egypt and Kenya. In this study, molecular and morphological analyses place the possible new species in the C. multipapillatum complex and was provisionally named C. multipapillatum E. Further analyses combining morphological and molecular approaches are required on adult specimens collected from piscivorous birds living in the same area to support the identification of a potentially new species. © 2022

Nematodes belonging to the genus Contracaecum (family: Anisakidae) are heteroxenous parasites with a complex life cycle. Contracaecum larvae infecting farmed fish and fishery products are economically important causing market rejection in massive infection and may have zoonotic potential. In Israel, Contracaecum larvae have been described morphologically in several fish species; however, none of these descriptions were supported by molecular tools. In 2019–2020, hybrid tilapia (Oreochromis aureus x Oreochromis niloticus) and red drum (Sciaenops ocellatus), farmed in polyculture were found to be heavily infected with nematodes referable to Contracaecum larvae. Prevalence of infection in hybrid tilapia and red drum was 53.8% and 40.9%, respectively. A combined (morphological and molecular) approach revealed that both infected fish species were parasitized by the same species of Contracaecum, although larvae in hybrid tilapia were localized in the pericardial cavity whereas in red drum, they were observed in the abdominal cavity. Genetic analysis of internal transcribed spacer rDNA and cox2 mtDNA showed high similarity to unidentified Contracaecum larvae detected in several fish species in Ethiopia, Egypt and Kenya. In this study, molecular and morphological analyses place the possible new species in the C. multipapillatum complex and was provisionally named C. multipapillatum E. Further analyses combining morphological and molecular approaches are required on adult specimens collected from piscivorous birds living in the same area to support the identification of a potentially new species. © 2022

Saprolegnia infections are among the main parasitic diseases affecting farmed salmonids. The distribution and potential transfer of Saprolegnia spp. between farms and the natural environment has been scarcely investigated. Therefore, this work aimed to study the diversity and abundance of oomycete species in salmonid farms, tributary water, and effluent water systems. Four trout farms in Italy and two Atlantic salmon farms in Scotland were considered. In Italian farms, 532 isolates of oomycetes were obtained from fish and water, at upstream, inside, and downstream the farms. In Scottish farms, 201 oomycetes isolates were obtained from water outside the farm and from fish and water inside the farming units. Isolates were identified to the species level through amplification and sequencing of the ITS rDNA region. In Italy, S. parasitica was significantly more present in farmed than in wild fish, while in water it was more frequently isolated from the wild, particularly in effluent systems, not associated with more frequent isolation of S. parasitica in wild fish downstream the farm. In Scotland, S. parasitica was the most prevalent species isolated from fish, while isolates from water were mostly Pythium spp. with few S. parasitica isolates from upstream and downstream the farms.

Here we present “Cephalopods’ Pathogenic Agents Database” (CephPAD), a free online resource collating data on parasites and other pathogenic agents of cephalopods. This is presented in an interactive database format and based on the information from ‘Diseases of Marine Animals’ (Kinne, 1990—chapters concerning cephalopods; Hanlon and Forsythe, 1990a, 1990b; Hochberg, 1990). The current data set includes viruses, bacteria, fungi and fungus-like organisms, Chormista and Protozoa. Metazoan parasites, i.e. Diciemyda, Monogenea, Trematoda, Cestoda, Acanthocephala, Nematoda, Annelida and Crustacea, are also included. The database also provides indications of possible effects of these agents in their host, such as affected tissue, anatomy-pathological findings, clinical presentation and prevalence of mortality. Additionally, information on structural abnormalities and neoplasia are also incorporated. If available, information about the cephalopod origin (i.e., wild or cultured) and place of capture is also included. Several species of cephalopods are included (about 130), and the these are presented based on the original taxonomic description and the updated one according to World Register Marine Species (WoRMS). This database is intended for researchers, students, technicians, care-takers and veterinarian to help ensure cephalopod welfare in captivity. We plan to regularly update this database with new published information as it becomes available. This work is the result of the activities of the COST Action FA1301

Coccidian parasites of the genus Aggregata are known to parasitize cephalopods as definitive hosts, however one of the genus members, A. octopiana, has shown an unresolved phylogeny within the same definitive host, the common octopus (Octopus vulgaris). Our study represents a large-scale investigation aimed at characterizing morphological traits and phylogeny of A. octopiana isolated from O. vulgaris inhabiting three distinct geographic areas of the central Mediterranean: The Adriatic, Ionian and Tyrrhenian Seas. The morphology of sporogonic stages of the parasite in octopus tissues was assessed by light and electron microscopy; molecular characterization has been carried out using the 18S rRNA locus. Our results support the hypothesis that two morphologically and genetically different A. octopiana infect O. vulgaris in the investigated areas of the Mediterranean Sea. Additional nuclear and mitochondrial markers for Aggregata should provide further information and better resolution of its phylogeny