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10In the Mediterranean Sea Nephrops (Nephrops norvegicus) is predominantly caught with 11 bottom trawls, but it is also harvested with creels. While the size selection of Nephrops in 12 bottom trawls is well documented, there is no previous information on creel size selection for 13 this species. Therefore, sea trials were carried out to assess the selective properties of 14 commercial creels with 41 mm mesh size netting mounted as a square mesh netting as 15 prescribed by the legislation. Creel size selection was assessed for Nephrops and two main 16 crustacean bycatch species: mantis shrimp (Squilla mantis) and blue-leg swimming crab 17 (Liocarcinus depurator). The influence of the soak time on creel selectivity was also 18 investigated, and no significant difference was detected between one and two day soak times. 19The average carapace length of a crustacean with 50% probability of being retained (L50) was 20 31.69 mm for Nephrops, which is 59% larger than the minimum landing size (MLS) set by 21 the fishery regulation, therefore demonstrating a mismatch between MLS and gear selectivity 22 in this fishery. Comparison of creel selectivity obtained in our study with the historical results 23 obtained from commercial bottom trawl selectivity studies for Nephrops in the Mediterranean 24 *Manuscript including abstract Click here to view linked References Sea demonstrated that the creel L50 was significantly higher than in the trawl fishery, this 25 implies that creel fishery is targeting larger Nephrops than trawl fishery. 26 27

Squids are especially frequent as paratenic hosts of helminth parasites, particularly to those that have elasmobranchs and mammals as final hosts. Among those parasite species, anisakid nematode larvae and cestode plerocercoids are most effectively transferred through the trophic chain by oegopsid squids. A total of 439 short-finned squids, Illex coindetii (245 males, 190 females and 4 unsexed) were sampled in the central part of the eastern Adriatic Sea in order to assess their helminth component community and parasite dynamics with respect to host sex, maturity, seasonality, and feeding behavior. Two larval helminths were isolated, i.e., larvae of Anisakis pegreffii, characterized by molecular tools at the species level, and plerocercoids of Phyllobothrium sp., with prevalences of 30.5% and 2.3%, respectively. Highly significant seasonal variation in diet consumption, congruent with seasonal variation in anisakid intensity, was observed, underlining the tight role of squid prey in the trophic transmission of parasite. Likewise, the highest helminth prevalence and intensity of infection was recorded in autumn, when the fish prey, mostly Maurolicus muelleri, comprised the greatest proportion of diet. This helped to assign the Adriatic broadtail shortfin squid not as a first, but as a second, paratenic host for the anisakid, unlike as suggested previously. The presence of larval A. pegreffii confirms its previously reported zoogeographical distribution in the Mediterranean and Adriatic Seas. The presence of 2 helminths in I. coindetii describes the feeding patterns of the squid, as well as clearly defined and coevolved predator-prey relationships.

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Sagittal otolith morphology and otolith shape of two megrim species, Lepidorhombus boscii and Lepidorhombus whiffiagonis, were compared using descriptive morphological characters and Wavelet shape coefficients. Differences in otolith shape were examined by linear discriminant analysis (LDA). The first discriminant axis explained 66.6% of the variation between the groups, and the second axis 28.5%. Otolith classification based on LDA showed that in 79.5% of cases an otolith can be correctly classified based only on its shape. Relationships between otolith morphometric parameters (length and width) and fish size (total length) were described by fitting simple linear regression models. For L. boscii the highest positive correlation was found between right otolith width and total body length (R2 = 0.82), and for L. whiffiagonis between left otolith length and total body length (R2 = 0.39).