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Otolith growth is a complex phenomenon integrating various factors that can be considered either as endogenous or exogenous, although they are always regulated by the physiology of the fish. The material incorporated into otoliths is not reabsorbed or subject to metabolic reworking, and growth is continuous. Thus otoliths are considered as very useful tools to study the various events that characterize fish life cycles. The otolith shape is species-specific and may vary within each species according to endogenous factors (size, sexual maturation), environmental factors (use of habitat, depth distribution) and individual factors. The ecomorphological link hypothesis of the otolith shape was carried out in relation to the life history, biological and behavioral characteristics of fish species, or the type of swimming activity (Lychakov & Rebane, 2000). Chelidonichthys cuculus (Linnaeus, 1758) and Chelidonichthys lucerna (L., 1758) are the two most-landed species of Triglidae (Teleostei, Scorpaeniformes) in Italian trawl fisheries. Triglidae are known for their sound producing ability in agonistic contexts related to territorial defense, reproduction, and competitive feeding also associated with growth. A previous study on sulcus acusticus morphometrics showed higher mean values of sulcus area/otolith area (S:O) ratio of adults than of the juveniles for C. cuculus. The crystals on sulcus acusticus were different in shape, size and arrangement between juveniles and adults. In juveniles the crystals were quite enmeshed in the otolith matrix and showed a rod/smooth-shape. The crystalline arrangement of adults became more complex and with a larger, rod/rectangular-shape and well-formed faces. These differences were associated with several changes in depth distribution, diet and physiology and a consequently different use of the auditory system with ontogeny. The aim of this study was to analyze the morphology and shape variations in otoliths (through geometrical indices and elliptic Fourier descriptors [EFDs]) of these two Mediterranean gurnards in order to use otolith as phenotypic markers for significant life stages.

Summary Stomach contents of 283 anglerfish (Lophius budegassa), collected in the Adriatic Sea (north-eastern Mediterranean) from experimental trawl surveys in 2005 and 2006, were examined to assess their diet as influenced by fish size, sex and water depth. Changes in food quantities in the stomach were observed, the percentage of empty stomachs decreasing with increasing body size and depth. No differences were found between male and female diets. The anglerfish is essentially an ‘opportunistic feeder’ that consumes mainly fishes, crustaceans and molluscs. Fishes were the primary food consumed by all size classes; the favourite prey was Merluccius merluccius (TL >150 mm for medium and large anglerfish) and Gaidropsarus biscayensis (TL

Summary Length–weight relationships were estimated for the first time for seven species of gurnards (Triglidae) based on data collected over the past 27 years in the Adriatic Sea (northeast Mediterranean). Results show significantly different relationships between juveniles and adults (females and males combined) for Aspitrigla cuculus, Eutrigla gurnardus, Chelidonichthys lucerna and Lepidotrigla cavillone. Isometric growth of juveniles is indicated for four species, allometric growth of adults for all species.