Living cells of the ciliate Mesodinium rubrum were observed and photographed during summer red-water events in the Southampton Water estuary, southern England. These blooms were characterized by increases in maximum cell diameter and range of cell size, a pronounced morphological variation of the ‘oral’ hemisphere, and the presence of free-swimming ‘fragments’ of larger cells.

Red-water occurrences caused by the planktonic, phototrophic ciliate Mesodinium rubrum (Lohmann) Hamburger & Buddenbrock, have been characterized by some of the highest recorded levels of chlorophyll and primary productivity for natural populations of marine phytoplankton (Lindholm, 1985; Taylor, 1982). However, as these events are rather unpredictable and all attempts to culture M. rubrum have failed, descriptions of the morphology of living cells have been rather limited. A study into the impact of red-tides caused by M. rubrum in the Southampton Water estuary presented a useful opportunity to observe morphological variation in living cells. Water samples were taken with a ‘Van-Dorn’ sampler, and transported in polyethylene bottles in a cool box. Living cells were observed and photographed at 400x magnification using the phase-contrast optics of an Olympus BH2 photomicroscope. Autofluorescence of living cells was examined using a Zeiss fluoresence microscope.

The full developmental embryonic sequence of Gobius cruentatus is described for the first time. Embryonic development lasted 13 days (14·0–15·0°C). The newly hatched larvae (3·3 mm total length) presented pigmented eyes, the yolk is fully absorbed, and the mouth and anus were opened allowing the onset of exogenous feeding almost after hatching.

Gills of fresh-water and sea-water eels were perfused at a constant pressure with physiological Ringer containing 10−6 M sodium orthovanadate and examined by light microscopy. The secondary gill filaments were markedly vasoconstricted in both freshwater and sea-water fish although the peripheral blood route around the secondary filaments was unaffected. The central venous space in the primary filament was largely unaffected. Significant constriction of both afferent and efferent arteries on the primary filament occurred. We conclude that orthovanadate vasoconstricts eel gills mainly at the level of the secondary filaments. The study also emphasizes that chloride cells are located on both the primary and secondary filaments of fresh-water gills but solely on the primary filaments of sea-water gills.

The number of diatoms, and the carbohydrate and organic matter in suspension, were followed during most of the year 1962 in Loch Striven.

A rise in diatom numbers was always accompanied by a rise in both carbohydrate and organic matter, but the agreement was not quantitative.

A recent inventory of the benthic Gammaridea: Amphipoda species on the French continental coastline catalogued 495 species. An analysis of the biodiversity and the biogeographic relationships that exist between the French Amphipoda: Gammaridea, living on the coastline that extends along 10° latitude range in the temperate region between 41° and 51° North and the other gammaridean faunas living in the north-eastern Atlantic has drawn the pattern of diversity in this marine invertebrate group on a large biogeographical scale. Gammaridean amphipods exhibit a latitudinal gradient over the total number of species, including the continental shelf species and the bathyal species. There are four main fauna groups, which correspond to the biogeographical zones of the north-eastern Atlantic: (1) a cold arctic and cool-temperate Svalbard and Norwegian coastal fauna; (2) a cool-temperate boreal and Boreal–Lusitanian United Kingdom, Irish and English Channel shallow fauna; (3) a warm-temperate Lusitanian Bay of Biscay and subtropical central Atlantic fauna; and (4) a subtropical Mediterranean fauna. The French fauna appears particularly rich, presenting 44% of the 1119 species recorded in the north-eastern Atlantic along the 50° latitude range (30°N–80°N).  

This is obviously due to France's intermediate latitudinal location within the Lusitanian temperate biogeographical zone, which produces a biogeographical cross between the boreal fauna in the north and the warm temperate and sub-tropical fauna in the south.

In a study investigating the composition and spatial and temporal variation of the benthic macrofauna associated to the discharge of domestic sewage off Fortaleza, north-eastern Brazil, a new species of Syllis was found. This new species, S. guidae sp. nov., is characterized by having blades of falcigers with subdistal tooth about same length as distal tooth, but stouter than it, with spines on cutting edge almost reaching the tip of subdistal tooth, blades of falcigers with conspicuous subdistal triangular process and unusually long anal papilla between anal cirri, measuring about one-quarter of their length. Syllis guidae sp. nov., is herein described and compared with the most similar congeners.

The structural parameters of sponge-dominated benthic communities from two Mediterranean caves in two seasons, autumn (November) and spring (June) were compared. The percentage of species in common between communities in each cave was calculated as a rough estimate of the capacity of species dispersion in each cave. The Shannon diversity index and Kulczynski similarity index were calculated for each community. Moreover, we studied the spatial distribution, patchiness and interspecies contacts of the most abundant species. The value of α-diversity was quite constant among communities of the Cabrera cave but decreased from the external to the innermost community in the Medes cave. The Kulczynski similarity index was generally lower among samples of the Cabrera cave. The most abundant sponge species showed a predominantly clumped distribution, especially in the most internal communities of the two caves. The innermost community of the Medes cave had the highest number of patches. Finally, the study of contacts among species that were non-random (meaning species that were in contact with a given species significantly more or less frequently than expected) showed that they were very common in the two seasons and in all communities, indicating the importance of biotic associations among benthic species in cave assemblages.

A twelve-month investigation was undertaken on how copepod community structure varied in relation to environmental factors in the Coleroon estuary, south-east India. Sampling was monthly, from Station 1 in the sea to Station 4 in the Vettar backwaters. Canonical correspondence analysis (CCA) was applied to elucidate the environmental factors affecting the copepod community. A total of 104 copepod species in 38 genera and 26 families were recorded, with the Calanoids, Acartia erythraea and Oithona brevicornis being the most dominant. At all four stations, both these species loaded near the intercept of CCA axes 1 and 2, perhaps reflecting that they were autochthonous. Most species occurred in distinct seasonal patterns. Abundances ranged from 13 × 103 to 215 × 103 (ind. m−3). Coleroon waters showed high diversity (bits/ind.), from 5.29 at Station 3 to 4.97 at Station 4. Abundance correlated positively with temperature and salinity and negatively with rainfall, dissolved oxygen concentration (DO) and pH. Species diversity correlated strongly with abundance (P < 0.01). Abundance and diversity were highest during the summer, and both correlated positively with salinity. Temperatures (air and water), salinity, pH and DO varied in the ranges 26–36°C, 25–34.2°C, 9–38, 7.0–8.7 and 3.0–6.8 ml l-1, respectively. Nitrate, nitrite, phosphate and silicate (µM) varied in the ranges: 4.7–64.5, 0.4–14.1, 0.2–12.9 and 9.3–148, respectively.

1. The characters of the species of “Portunus” are redescribed in detail and comparatively.

2. On the basis of the characters studied an attempt is made to determine the relationships of the constituent species, both within the genus and with allied genera, P. corrugatus and P. arcuatus, being regarded as the more primitive forms.

3. P. marmoreus and P. holsatus are separated by a large number of characters.

4. The status of various foreign, fossil and doubtful species is discussed.

5. An account is given of the present state of knowledge regarding the distribution of the species.

6. The synonymy of the generic name is considered at length.

Ectoparasitic crustaceans (Copepoda: Caligidae) occurred at considerable frequency in stomach contents of young specimens of Diplodus sargus and Diplodus puntazzo (Pisces: Sparidae) from two central Mediterranean coastal lagoons. This finding suggests that the ectoparasites might give a non-negligible contribution to the diet of the studied fish species and reveal a certain adaptive advantage of cleaning behaviour in coastal environments.

The ichthyoplankton of Galway Bay was sampled over the spring and summer of 2007 and 2008 to determine what environmental factors influenced the distribution of larval and early juvenile fish. A total of 549 fish representing 27 taxa were caught. Catches decreased throughout each sampling season, and were generally poor in 2007. Catches were numerically dominated by sprat (Sprattus sprattus), dab (Limanda limanda), sand eel (Hyperoplus immaculatus) and whiting (Merlangius merlangus). Environmental factors driving distribution of fish were modelled using a binomial generalized linear model. The strength and direction of wind in the five days preceding sampling was the only significant environmental factor. Sustained onshore winds increased the probability of encountering larval fish in the areas sampled. The rainfall, tidal state, tow depth and wind conditions during sampling were not significant. Among the parameters measured it appears that onshore winds sufficiently strong to overcome the residual circulation are the main physical driver for the distribution of larval fish in Galway Bay.

Thalassomonhystera bathislandica sp. nov. (Nematoda: Monhysteridae) was found in abundance in a few gelatinous phytodetritus aggregates collected from the surface of bottom sediments in the north-eastern Atlantic at depths of about 4000 m. The new species resembles T. islandica (De Coninck, 1943), an inhabitant of saltmarshes. Viscous detrital aggregates, including sediment agglutinations made by the nematodes themselves, are perceived as the preferred habitats of nematode species in fluffy surficial muds. It is suggested that physical constraints prevent nematodes from a fast invasion into freshly sedimented, loose detritus deposits.

Habitat modelling requires incorporation of both biotic and abiotic information. For juvenile flatfish the factors that most influence growth are water temperature, food abundance and predatory pressure. This study focuses on the impact the predator, the shore crab, Carcinus maenas, has on the foraging activity of sole, Solea senegalensis. The results show that in the presence of both prey (ragworm, Nereis diversicolor) and predator, ≃10% decrease in foraging activity is observed when compared to the sole in the presence of only food. This suggests that when the shore crab is present, Senegalese soles are not only affected by direct predation but sub-optimal foraging is also found. Behaviours most correlated with foraging were crawling and tapping and these activities were also affected by the presence of the predator. This study also provides further support for visual recognition of predators and olfactory prey recognition in the Senegalese sole. Predator–prey encounters shape species behaviours profoundly and have to be looked at from different levels of ecology, behaviour and modelling.

The age and growth of the snowy grouper, Epinephelus niveatus, from central and south-eastern Brazil were studied by otolith analysis from a sample of 341 specimens, ranging from 325 to 1216 mm in total length (TL) caught with bottom longlines between 1996 and 1998. Otolith length grew proportionally with the increasing TL of the fish. Marginal increment analysis indicated that a single opaque band forms each year during autumn–winter. The maximum estimated age was 54 years, which significantly extends the previously estimated life-span of 21–29 years for this species. The von Bertalanffy growth parameters for both sexes were estimated as L∞ = 1098.4 mm TL, K = 0.062 year −1 and t0 = –2.68. The study revealed differences in mean length-at-age and size at recruitment, as well as in growth parameters between the central and the south-eastern Brazilian coast, which can be attributed mainly to different fishing pressures. The snowy grouper was found at depths of 82–492 m, and showed a positive relationship between age and depth, suggesting differential movements of older fish to deeper waters.

A new species of Abyssoninoe (Polychaeta: Lumbrineridae) has been found on sublittoral soft bottoms in the Gulf of Milazzo (central Mediterranean Sea). The description is based on eleven specimens recorded in six grab samples carried out by Van Veen grab from 20 to 50 m depth. Abyssoninoe bidentata sp. nov. differs from the six hitherto known species of Abyssoninoe by having the maxillae III with two subequal teeth instead of one, the shape of the parapodial lobes and chaetal distribution.

The community structure of shallow rocky reef fish fauna of the Azores Archipelago is described from underwater visual censuses carried out at eight areas (Terceira and Corvo Islands). A total of 52 fish species from 26 different families was observed, and the ten most abundant fish corresponded to 82.7% of all fish. Trophic categories are given for observed species with comments on distribution and densities along sampled depth strata. Mean densities along sampled strata were tested for significant differences. Sparidae, Labridae and Carangidae were the most speciose families being Diplodus sargus, Pagellus acarne, Coris julis, Thalassoma pavo and Tripterygion delaisi the most abundant species that consequently also accounted for the highest densities.

The rDNA repeat-unit of the vent polychaete Alvinella pompejana was investigated using restriction analysis. Mapping revealed evidence of rDNA polymorphism within and between individuals which was due to individual restriction site variation and sequence rearrangements involving spacer regions. The size of the repeat unit was 10.5 kb with virtually no evidence of length variation. Sequence inversions indicated the presence of two spatially-distinct subfamilies of repeats, probably on different chromosome pairs. Animals from contrasting vent habitats with respect to age and chemical emissions (young vs old chimneys and white vs black smokers) from within the 13°N/EPR (East Pacific Rise) vent sector were analysed for evidence of population differentiation. Based on individual restriction site variation, average FST estimates across neighbouring populations were in the region of ~0.05 and differed significantly from zero. This level of genetic differentiation is comparable to values reported previously for allozymes. Spatial and temporal allelic frequency variances estimated from pairwise combinations (i.e. s2S and s2T) strongly suggested that differences in allelic frequency were the result of repeated extinction/recolonization events associated with the vent instability. Estimates of the effective population size derived from standardized temporal allelic frequency variances Fks were very low compared to actual population size indicating great temporal fluctuations in the former. Theoretically, such an effective population size is not sufficient to maintain the observed level of polymorphism within the 13N/EPR vent sector. Results are therefore consistent with a ‘propagule’ colonization-type model in which extinction/recolonization rates are high. In Alvinella, planktonic larval dispersal appears sufficient to overcome any genetic differentiation resulting from drift, but these findings also indicate that propagules may only be capable of dispersing a few tens of kilometres per generation.

The distribution of the larvae of four of the five species of Ammodytidae occurring in Scottish waters is examined. The two most abundant species, Ammodytes marinus Raitt and Gymnammodytes semisquamatus (Jourdain) are described in detail and their abundance recorded. A. marinus larvae were found throughout the survey area, but were most abundant in the Moray Firth and around Orkney. G. semisquamatus larvae were most abundant along the north and west coasts, although they were recorded in a few areas off the east coast of Scotland. A. lanceolatus Lesauvage larvae occurred generally in Scottish waters, although few larvae were caught. A. immaculatus Corbin larvae, which have not previously been recorded in the Scottish area, were also rare and were restricted to areas off the north and west coasts. The material was not suitable for demonstrating the distribution of larvae of A. lancea Raitt. The occurrence of larvae is related to the spawning season of each species.

Whole flounder serum has been fractionated by gel filtration on Ultrogel AcA22. Pooled material from the first major peak of the elution profile was further fractionated by FPLC ion-exchange chromatography and this yielded one major and three minor peaks. Under both reducing and non-reducing conditions SDS electrophoresis showed that the major peak and two of the minor ones were immunoglobulin (Ig). All three of these Ig populations were tetrameric, with estimated molecular weights of 710 kD. However, approximately 90% of the major Ig species consisted of tetramers which were covalently linked by disulphide bonds, whereas the remaining 10% was composed of dimeric molecules held together by non-covalent interactions. The heavy chains of all three Ig populations had apparent molecular weights of approximately 72 kD but the light chain composition showed considerable heterogeneity. In the major population, five polypep-tides were detected in the light chain region of the gel with apparent molecular weights covering the range 22–28 kD. However, there was no difference in the light chain composition of covalently and non-covalently linked tetramers. The two minor populations differed both from each other and from the major species in respect of their light chain compositions. No evidence was found for a monomeric serum Ig, and alkaline urea electrophoresis failed to demonstrate a J chain.