The European squid Loligo vulgaris inhabits the continental shelf of the North and Central Atlantic and the Mediterranean Sea, with significant socio-economic value for the associated fisheries. Globally, the stock appears to be maintained at levels close to the optimal sustainable yield, but capture statistics indicate high fluctuations in fisheries production, and some regions might be affected by overexploitation. In this study, we used the mitochondrial marker mtCOI to investigate temporal and spatial genetic structure and variability in the European squid in the eastern part of the Adriatic Sea and put it into context with its Mediterranean and Atlantic conspecifics using data from public databases. High haplotype and low nuclear diversity of mtCOI were detected, with no significant genetic differentiation, suggesting one panmictic homogeneous population in the North and Central Adriatic Sea. The Adriatic cluster appears to diverge from its Mediterranean–Atlantic conspecifics; however, this pattern should be considered preliminary due to the limited and uneven geographic sampling available in public databases. The current dataset lacks comprehensive coverage of several Mediterranean sub-basins, which restricts the resolution of connectivity patterns and may mask subtle population structure. Despite these limitations, our results provide an important baseline for understanding the L. vulgaris Adriatic stock and for developing joint management policies among all countries that exploit this shared resource.

Background/Objectives: Non-indigenous species are increasingly reshaping Mediterranean marine ecosystems, particularly under ongoing climate warming. The rayed pearl oyster Pinctada radiata, a thermophilic species originating from the Indo-Pacific region, is one of the earliest and most successful invaders in the Mediterranean Sea and has recently established populations in the Adriatic Sea. Methods: This study integrates preliminary shell morphometric data with molecular genetic analyses based on mitochondrial cytochrome c oxidase subunit I (COI) and nuclear internal transcribed spacer 2 (ITS2) markers to confirm species identity and examine patterns of genetic variation in comparison with other Mediterranean Sea regions and the Persian Gulf. Results: Phylogenetic analyses based on COI confirmed P. radiata as a distinct and well-supported monophyletic lineage, whereas the nuclear ITS2 marker showed limited resolution and interspecific overlap. Mediterranean and Adriatic populations showed low COI haplotype and nucleotide diversity and weak genetic structuring, consistent with recent colonization and secondary expansion, whereas Persian Gulf populations were more genetically diverse. Conclusions: Future studies should employ larger sample sizes and broader geographic sampling across both the Mediterranean Sea and the full native range of P. radiata, combined with high-resolution genome-wide nuclear markers, to better resolve connectivity and invasion dynamics.

Background: Creatine is one of the most widely used dietary supplements for enhancing physical performance and is increasingly investigated for a range of health-related applications. Although creatine monohydrate is the most commonly used formulation, concerns have been raised regarding its oral bioavailability, prompting the development of alternative formulations and delivery strategies. However, it is unclear to what extent randomized controlled trials (RCTs) evaluating oral creatine supplementation address issues related to bioavailability. Therefore, we aimed to assess how bioavailability of oral creatine is considered and reported in RCTs. Methods: We conducted a meta-research study of published RCTs in which orally administered creatine was used as an intervention or comparator, regardless of participant characteristics or outcomes. MEDLINE and Embase were searched from inception to 1 March 2024. We extracted data on trial characteristics, creatine formulations used, mentions of bioavailability, and comparisons between different creatine products. Data were summarized descriptively. Results: We included 357 reports corresponding to 343 RCTs published between 1994 and 2023. Creatine monohydrate was the most commonly used formulation, reported in 275 (80.2%) trials; however, 53 (15.5%) reports did not specify the exact creatine form used. Bioavailability was mentioned in only 38 (11.1%) reports, most frequently in the discussion section. Four trials (1.2%) reported specific measures intended to enhance bioavailability, including instructions regarding supplement dissolution or co-ingestion with food or carbohydrates. Five trials (1.5%) compared more than one creatine formulation, but only three (0.9%) discussed bioavailability. These formulation comparisons were frequently limited by non-equimolar dosing regimens. Conclusions: RCTs of oral creatine supplementation rarely address bioavailability and often provide insufficient information on the exact creatine formulation used. Few trials reported strategies to enhance bioavailability, and direct comparisons between creatine formulations were uncommon and methodologically limited, particularly because of non-equimolar dosing. Future trials should improve reporting of creatine formulations, incorporate bioavailability-related outcomes, and use appropriate dosing strategies when evaluating alternative creatine products.