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In order to assess diet composition and niche breadth of this species, we analysed the stomach content of 182 specimens collected monthly along the eastern coast of Sicily (Central Mediterranean Sea). Overall, 50 prey taxa belonging to five major groups (algae, gastropods, crustaceans, polychaetes, fishes) were identified in 102 full stomachs. Benthic or epibenthic crustaceans, such as decapods, amphipods and isopods were the most important prey, whereas algae, gastropods, polychaetes and fishes were only occasionally ingested. In terms of composition by species, the diet of Scorpaena maderensis was characterized by a variety of rare or unimportant prey, which was consumed by few individuals only, although sometimes in large amount. As a result, S. maderensis can be considered a generalized and opportunistic feeder. The feeding intensity followed roughly a seasonal trend, with a minimum food intake in summer. The individual fish size was the most important factor affecting diet. According to the observed ontogenetic shift, small-sized individuals fed primarily on small crustaceans (i.e. amphipods and isopods), whereas large-sized specimens consumed preferably bigger and more vagile prey, such as walking and swimming decapods. No significant differences in diet were observed in relation to sex of predator and sampling season. [ABSTRACT FROM AUTHOR]

This study investigated demographic structure and reproductive characteristics of the Atlantic mackerel Scomber scombrus, in relation to landing trends in the northern-central Adriatic Sea. Results highlighted the occurrence of only small-sized and young-age individuals, and a marked decline from the 1990s to the present in maximum age (from 8 to 3 years) and total length (L(T); from 420 to 360 mm). Fecundity ranged between 40,000 and 190,000 eggs, and was related to female L(T). High levels of atresia implied lower values of actual fecundity. Sexual maturity was attained by 72·8% of individuals in their first year of life at 200 mm. The reduction in maximum L(T) resulted in a marked decline in the population egg production, while the reduction in maximum age implied that females participated in fewer spawning events., (© 2013 The Fisheries Society of the British Isles.)

Pelagic gobies are considered of particular zoological interest because the acquisition of a pelagic lifestyle is achieved through the persistence of larval anatomical features. The Mediterranean Sea is inhabited by three goby species (Aphia minuta, Crystallogobius linearis and Pseudaphya ferreri) characterized by paedomorphic traits. Owing to the shared larval morphological features, these species have generally been considered as a monophyletic group. This study aimed at establishing the phylogenetic relationships of these paedomorphic species within the family Gobiidae to ascertain whether the pelagic lifestyle achieved through paedomorphosis is due to an event that took place in a common ancestor or not. For this purpose, we amplified by polymerase chain reaction and sequenced the mitochondrial 12S rDNA (complete sequence) and 16S rDNA (partial sequence) of 15 Mediterranean gobies. The phylogenetic analysis strongly supported the polyphyletic origin of the three paedomorphic gobies, indicating that the heterochronic change leading to the retention of larval features seems to have occurred independently in the ancestors of these species. Thus, the sharing of morphological traits can be considered homoplasious and the classification of these species in the same taxonomic group is rejected on the basis of molecular data., (2007 Wiley-Liss, Inc)