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The common dentex, Dentex dentex, is a fish species which inhabits marine environments in the Mediterranean and Northeast Atlantic regions. This is an important species from an ecological, economic and conservation perspective, however critical information on its population genetic structure is lacking. Most samples were obtained from the Mediterranean Sea (17 sites) with an emphasis around Corsica (5 sites), plus one Atlantic Ocean site. This provided an opportunity to examine genetic structuring at local and broader scales to provide science based data for the management of fishing stocks in the region. Two mitochondrial regions were examined (D-loop and COI) along with eight microsatellite loci. The COI data was combined with publicly available sequences and demonstrated past misidentification of common dentex. All markers indicated the absence of population genetic structure from the Bay of Biscay to the eastern Mediterranean Sea. Bayesian approaches, as well as the statistical tests performed on the allelic frequencies from microsatellite loci, indicated low differentiation between samples; there was only a slight (p = 0.05) indication of isolation by distance. Common dentex is a marine fish species with a unique panmictic population in the Mediterranean and likely in the Atlantic Ocean as well. [ABSTRACT FROM AUTHOR]

The article offers information on the fish occurrence of fish genus Dentex and the species Dentex canariensis Steindachner that is found in the Mediterranean Sea. Topics discussed include the total measurements of the fish that is its length and weight, the interaction of Dentex genus with its Dentex species, and the impact of climate change on these fish.

The article discusses a research study on the parasite from the fishes Dentex canariensis and D. gibbosus in the Mediterranean Sea and Atlantic Ocean known as Lamellodiscus euzeti N. of the species Monogenea: Diplectanidae. Collected were 27 specimens of Dentex canariensis and 48 Dentex gibbosus fishes from Ouakam and Soumbedioune fish markets in Senegal and four Dentex gibbosus from the Tunisian Sfax fish market then dissected, frozen and examined. Results showed 70% prevalence of D. canariensis from off Senegal in 19 infected out of the 27 fish examined, 67% prevalence of D. gibbosus from off Senegal in 32 infected out of the 48 fish tested and 100% prevalence of D. gibbosus from off Tunisia on the four infected fish examined.

The seasonal distribution of Morocco dentex ( Dentex maroccanus) was investigated in relation to ocean environmental conditions in the NE Mediterranean Sea. Data were collected during a 2-yr period (1996–1997) of quasi-synoptic seasonal sampling using demersal trawl surveys. The study revealed evidence for the existence of environmental relationships and temporal habitat associations of Morocco dentex. The sea-bottom salinity, the water depth (through its interaction with bottom salinity) and the spatial location appeared to be key determinants of distribution. There was a strong consistency in the pattern and significance of the observed relationships across all seasons. The present results provided direct support for a preferential seasonal aggregation of Morocco dentex in specific geographic and bathymetric regions of the study area. In all four seasons, these favourable regions were found to be relatively stable and distinct, had the highest catch-per-unit-effort index, and were located over shallower grounds (50–70 m) having bottom salinity around 39.1. The current findings also indicated that, throughout the year, the species was confined below the thermocline and avoided the deeper waters (>80 m). Morocco dentex ecological preferences for certain sea-bottom salinities, water depth zones and hydrographic regimes were suggested to contribute to the processes governing differential settlement to preferred grounds. [ABSTRACT FROM AUTHOR]