The importance of the age when evaluating mercury pollution in fishes: the case of Diplodus sargus (Pisces, Sparidae) in the NW Mediterranean

The aim of this study was to analyse the concentration of mercury (Hg) in the muscle of a common littoral, omnivorous fish such as the white seabream, Diplodus sargus, and to evaluate its relationship with the age and size of the specimens. Large, older predatory fishes have typically been the main target species for risk assessment of Hg intake in humans. The white seabream is neither a big fish nor a predator, but all sizes of NW Mediterranean specimens of this species showed high levels of Hg, with clear increases in older specimens. In addition, although the Se:Hg molar ratio was high and could reduce the impact of high concentrations of Hg in smaller fishes, it could not in the older specimens of D. sargus analysed because it decreased with age. This is not a major concern for human health because the white seabream is not a widely consumed species. However, in special situations involving toddlers, children and women of childbearing age, problems might arise if the white seabream or similar species are consumed in place of those that current recommendations advise against eating. In these cases it is very important to consider the species of fish consumed in each country and carefully assess the risk of Hg intak

Notes florístiques i corològiques, 707- 712

Notes florístiques i corològiques del Baix Empord

Reproductive morphology in Mediterranean Seirospora giraudyi (Ceramiales, Rhodophyta)

This paper presents a detailed description of the reproductive characters of Mediterranean Seirospora giraudyi based on fresh material collected in the northwestern coast of Spain. Vegetative cells are uninucleate. The plant is monoecious. Spermantangial parent’s cells are clustered on modified dwarf determinate filaments, usually situated on adaxial surfaces of branches. One to four spermatia are formed by elongation and proximal divisions of the spermatangial parent cells. Spermatium with a nucleus situated ina mec. The thallus is procarpic. The four-celled carpogonial branch is initially L-shaped, and it is situated on a periaxial supporting fertile axial cell. The mature carpogonial branch is U-shaped and the supporting cell and second periaxial cell enlarge and divide transversely to reproduce a pair uninicleate auxiliary cell. The nucleus in the ferlilized carpogonium divides twice and the carpogonium cleaves vertically into two cells that, turn, cut off a pair of uninucleate connecting cells that fuse with the auxiliary cells on opposite sides; the diploid nuclei in the connecting cells divide at the site of fusion and one of the nuclei enters the auxiliary cell white the other is extruded. Each auxiliary cell gives to a terminal primary gonimolobe initials. Gonimolobes form lax chains of carposporangia. As the gonimoblasts mature, both lobes of the foot cell which is situated on the supporting cell elongate the upper one secondary connecting with the supporting cell, and the lower one with the fertile axial cell. The gonimoblasts are subtended at maturity by one to several clusters of involucral flaments. Seirospora is currently placed in the tribe Euptiloteae; however the reproductive character of S.giraudyi is dentical to those described for the Cañllithamnieae. Molecular studies are needed to confirm the taxonomic position of S.giraudyi as well as that of the other species placed Seirospor

Vegetative and reproductive morphology of Kallymenia patens (Kallymeniaceae, Rhodophyta) in the Mediterranean Sea

Reproductive morphology of the Mediterranean red alga Kallymenia patens is described for the first time, confirming its position in the genus. K. patens is characterized by a non-procarpic female reproductive apparatus, carpogonial branch systems consisting of supporting cells bearing both three-celled carpogonial branches and subsidiary cells that lack a hypogynous cell and carpogonium; fusion cells develop numerous connecting filaments, and tetrasporangia are scattered over the thallus and are probably cruciately divided. Old fertile spathulate specimens of K. patens are morphologically similar to K. spathulata, but they can be distinguished by the length of spathulated proliferations (up to 0.6 cm and 6 cm, respectively), the length of inner cortical cells (up to 70 and 30 μm, respectively), and the gonimoblast location (in proliferations from the perennial part of the blade and over all the thallus surface, respectively

Geographical Distribution, Habitat and Reproductive Phenology of the Genus Kallymenia (Gigartinales, Rhodophyta) from Catalonia, Spain

Geographical distribution, habitat and reproductive phenology of the Genus Kallymenia (Gigartinales, Rhodophyta) from Catalonia, Spai

Phytosociological analysis of the community of Cystoseira mediterranea Sauvageau form Palamós (North-Western Mediterranean)

S'ha realitzat una anàlisi fitosociològica de la comunitat de Cystoseira mediterranea de la Punta del Molí (Palamós; Mediterrània nord-occidental). Els resultats mostren que la comunitat esta afectada per una elevada estacionalitat, que es tradueix en la dominància de Cystoseira mediterranea (Phaeophyceae, Fucales) durant la primavera-estiu, i la dominància a la tardor-hivem de diferents espècies de coral·linals, que formen part del subestrat erecte i incrustant (Corallina elongata, Lithophyllum incrustans), o bé són epífites als caulidis de Cystoseria mediterranea (Jania rubens, Titanoderma pustulatum). Les ceramials són només puntualment abundants, pero qualitativament són dominants a la comunitat durant tot l'any. La vegetació de la comunitat de Cystoseira mediterranea de Palamós es pot considerar com a típicament foto fila infralitoral de mode batut, per la gran abundància del grup PhIB. En els períodes més desfavorables per les especies d'aquest grup (tardor-hivern), es desenvolupen altres especies de requeriments ecològics menys estrictes dels grups ISR (infralitorals de substrat rocós) i PhI (fotòfiles infralitorals). Els grups esciòfils es troben precariament desenvolupats a la comunitat, però són sempre presents en el subestrat. La comunitat estudiada té una gran semblança amb les comunitats de Cystoseira mediterranea o d'especies vicàries d' aquesta descrites de la Mediterrània per altres autors.The authors studied on a quantitative and qualitative basis the vegetation of the community of Cystoseira mediterranea, applying phytosociological criteria. Results show that the community is affected by a high seasonality, with dominance of Cystoseira mediterranea (Phaeophyceae, Fucales) during spring-summer, and dominance, in autumn-winter, of several species from the order Corallinales. These species constitute the lower level and the encrusting layer (Corallina elongata, Lithophyllum incrustans), or live epiphytic over the stalk of Cystoseira mediterranea (Jania rubens, Titanoderma pustulatum). The Ceramiales, the qualitatively dominant group all year round, are also abundant in some periods of the year. The vegetation of the community can be considered as photophilous infralittoral of wave washed shores, but in the less favorable periods for the algae of this group (autumn-winter) , other species with less strict ecological requirements (from the ISR -infralittoral of rocky shores and the PhI-photophilous infralittoral) develop. The sciophilous groups are precariously developed, but they are always present at the lower level. The studied community is similar to other Mediterranean communities of Cystoseria mediterranea and to other communities dominated by vicariant species of Cystoseira mediterranea

Effects of the sewage pollution in the structure and dynamics of the community of Cystoseira mediterranea (Fucales, Phaeophyceae)

We performed a study on the specific composition, structure, and dynamics of two Cystoseira mediterranea communities from the north-western Mediterranean submitted to different degrees of pollution. The structural complexity (species richness, specific distribution, and species and pattern diversity) and biomass production were lower in the polluted site. In this station, opportunistic algae (mainly Ulva rigida) loomed, and Mesophyllum lichenoides and some encrusting brown algae increased their cover. Other species (Jania rubens, and some Ceramiales) decreased their abundance when compared with the polluted sit

Marine Invasion in the Mediterranean Sea: The Role of Abiotic Factors When There Is No Biological Resistance

The tropical red alga Womersleyella setacea (Rhodomelaceae, Rhodophyta) is causing increasing concern in the Mediterranean Sea because of its invasive behavior. After its introduction it has colonized most Mediterranean areas, but the mechanism underlying its acclimatization and invasion process remains unknown. To understand this process, we decided i) to assess in situ the seasonal biomass and phenological patterns of populations inhabiting the Mediterranean Sea in relation to the main environmental factors, and ii) to experimentally determine if the tolerance of W. setacea to different light and temperature conditions can explain its colonization success, as well as its bathymetric distribution range. The bathymetric distribution, biomass, and phenology of W. setacea were studied at two localities, and related to irradiance and temperature values recorded in situ. Laboratory experiments were set up to study survival, growth and reproduction under contrasting light and temperature conditions in the short, mid, and long term.Results showed that, in the studied area, the bathymetric distribution of W. setacea is restricted to a depth belt between 25 and 40 m deep, reaching maximum biomass values (126 g dw m−2) at 30 m depth. In concordance, although in the short term W. setacea survived and grew in a large range of environmental conditions, its life requirements for the mid and long term were dim light levels and low temperatures. Biomass of Womersleyella setacea did not show any clear seasonal pattern, though minimum values were reported in spring. Reproductive structures were always absent. Bearing in mind that no herbivores feed on Womersleyella setacea and that its thermal preferences are more characteristic of temperate than of tropical seaweeds, low light (50 µmol photon m−2 s−1) and low temperature (12°C) levels are critical for W. setacea survival and growth, thus probably determining its spread and bathymetric distribution across the Mediterranean SeaThis work was supported by an European Union reintegration grant (ERG-2009-248252) and a grant from the Spanish Ministry of Science and Innovation (CGL2004-05556-C02-01). Dr. Cebrian was funded by a Juan de la Cierva program (JCI-2008-02753) of the Spanish Science and Innovation Ministr

A synoptic key to the Rhodophyta of the Western Mediterranean. Part. I. Gigartinales, Halymeniales, Hildenbrandiales and Plocamiales

A synoptic key for identifying the Gigartinales, Halymeniales, Hildenbrandiales and Plocamiales from the Western Mediterranean has been prepared in order to facilitate the recognition of these res algae. The orders Gigartinales with some 69 species grouped in 19 families and 35 genera, Halymeniales, with 13 species grouped in 2 families and 6 genera, Hildenbrandiales with 1 family and 1 genera of 3 species, and Plocamiales, with 1 family and 1 genus of 2 species are included. The genus Wudermannia Harvey is also included in the key, althought it has not finally been established whether it belongs to the order Gigartinales or not. Morphological and anatomical descriptions of the reproductive structures, using data from the literature and from personal observations are presente