An investigation of spontaneous bioluminescence as related to sonic-scattering layers was undertaken off Fuerteventura, in the Canary Islands. The apparatus used is described. A definite increase in the magnitude of luminescence at scattering-layer depths is demonstrated. It is shown that the amount of luminescence forward of, and in the net of an Isaacs-Kidd trawl, is very much greater than that either above or below it. A frequency is disclosed within a single flash, and it is hypothesized that this may be a specific property.

At the period of sexual reproduction of the rhizocephalan parasite, Sacculina polygenea, the sacculinized crab, Hemigrapsus sanguineus, can serve as a temporary carrier for juvenile bivalve molluscs, Mytilus trossulus and Hiatella arctica as facultative epibionts. Such epizoans are never found on the crabs without the rhizocephalan externae or scars produced by the externae. The correlation between sacculinization and the bivalve epibionts is presumably due to maternal ‘brooding care’ with altering grooming behaviour of the crabs infested by S. polygenea.

This study examines the effect of water temperature on the formation of shell sculpture in young molluscs of the genus Hiatella. The larvae of H. arctica and H. gallicana were maintained under laboratory conditions at different temperature regimes. The animals were reared from late veligers to juveniles with a shell length of 700 μm. The results of the experiment showed that the shell sculpture, which is a diagnostic species character, was developed to various degrees at different temperatures. The larvae of each species grew to juveniles with variously pronounced shell sculptures ranging from a complete absence of sculpturing to its maximum development. The individuals with smooth shells like those of H. gallicana were the most abundant among the molluscs reared at +5°С. At +12°С, all molluscs formed ridges and two rows of long spines in the posterior portion of the shell, which is typical for H. arctica. At +8°С, the molluscs developed various intermediate forms of shell sculpture. It was, therefore, demonstrated that the development and prominence of shell sculpture is determined by environmental temperature. These results are discussed with regards to the validity of using shell sculpture as a taxonomic character for species in the genus Hiatella.

The growth and the reproductive cycle of Littorina littorea were investigated in the Ria de Aveiro, Portugal, a country cited as the southern limit of the species distribution in Europe. Littorina littorea growth is well represented by the von Bertalanffy equation SH=24.6[1-e-0.69(t-0.70)] where SH is the shell height (distance from shell apex to the basis of the aperture measured in mm) and t is the number of winters: after periwinkles have reached a mean SH of 4.6 mm in their first winter they grow progressively to about 14.6 mm, 19.6 mm, 22.1 mm and 23.4 mm in the following four years and they attain the asymptotic mean maximum SH of 24.6 mm at the tenth year if they survive. Ripening of the gonads occurred from October to May but was more intense from December to February, whereas spawning extended from January to May in females and November to May in males. There was a seasonal shedding of the male penis at the end of the breeding season (summer) accompanying regression of the testis.

As many Arctic fish species are intermediate hosts of anisakids, they are present in the diet of the ringed seal, Pusa hispida, and the bearded seal, Erignathus barbatus. Parasitic nematodes from the stomachs of 66 seals caught in the Nunavut region (Canada) from two communities (Arviat and Sanikiluaq) from October 2007 to January 2008 have been examined in order to identify the epidemiological risk for Inuit communities who consume traditional food. In Arviat 2428 anisakids were observed in 37 seals, while in Sanikiluaq 316 Anisakidae were isolated from 29 seals. The worms were treated with a host tissue, washed in deionized water and stored until analysis in 70% ethanol. The parasites were divided into three parts. The anterior and posterior parts were stored in 70% ethanol containing 5% glycerol and were examined using a light microscope by evaporation of the ethanol/glycerin mixture. The central parts were prepared for molecular identification by fixing in 70% ethanol. Using the polymerase chain reaction–restriction fragment length polymorphism (PCR–RFLP) method, the following members of the family Anisakidae were identified: Contracaecum osculatum A and C and Pseudoterranova bulbosa. In the studied material, more adult worms were noted than larval stages. The most numerous nematodes were P. bulbosa, and mixed infection was observed. The mean prevalence of anisakids infection was 43.2% in the Arviat and 37.9% in the Sanikiluaq communities.

Understanding the structure and richness of natural communities is a fundamental goal of marine ecology, and foundation species such as large macroalgae have a disproportionate role in structuring biodiversity. However, high-resolution information on assemblages associated with macroalgae is lacking for many species and regions. Saccorhiza polyschides is a warm-temperate kelp with a relatively short lifespan (12–18 months), large thallus and bulbous holdfast offering habitat for diverse assemblages. In the UK, S. polyschides populations are thought to have proliferated recently. Here, we quantified the density and habitat structure provided by S. polyschides along a gradient of wave exposure within Plymouth Sound, and examined the composition and diversity of associated faunal assemblages. Density varied significantly between sites but not by wave exposure, while biometric measurements were generally highly variable. Senescing holdfasts from sporophytes offered valuable habitat, with high abundance and richness of associated assemblages, although these varied markedly between sporophytes and sites. Faunal abundance, taxon richness and diversity were significantly higher at fully exposed sites than at moderately exposed sites. Internal volume of holdfasts was positively correlated with faunal abundance and taxon richness. We recorded more than 27 distinct taxa and up to ~600 individuals within a single holdfast. Taxa included three fish species, including a novel observation of the pipefish Nerophis lumbriciformis. Further work is needed to examine seasonality in habitat structure and associated diversity patterns but our study demonstrates that even remnant holdfasts from decaying sporophytes represent a valuable microhabitat that may provide shelter, protection and food during winter.

Anadara demiri (Piani, 1981) is an alien species in the Mediterranean Sea extending its range from Turkey westernly to the Adriatic Sea, where it is locally abundant. The species was first identified as Arca amygdalum Philippi, 1847 in the 1970s. The locus typicus of A. amygdalum is China. This first identification has never been discussed and the species has been thought to be of Indo-Pacific origin to date. However, in the Indo-Pacific province no Anadara shows any similarity with A. demiri. Morphological and molecular data suggest A. demiri is closely related to Anadara transversa (Say, 1822), a common species of the eastern coasts of North America. Anadara demiri is hence considered a junior synonym of A. transversa and the origin of this immigration has to be searched in the southern range of this species, maybe the Gulf of Mexico coasts of Florida.

Temporal variations over short and medium time scales play an important role in fish assemblage dynamics, but have been poorly investigated in tropical estuaries. This study evaluates the hypothesis that fishes co-occurring on a tidal mudflat have different patterns of temporal segregation at short- and medium-term scales that optimize resource use and habitat partitioning. A total of 6222 individuals and 66 fish species were caught during different hours covering the entire 24 h cycle, tidal regimes and the wet and dry seasons. Biomass and species richness, and to a lesser extent CPUE and evenness, showed statistically significant interactions across short- and medium-term scales. Biomass was higher during the dry season and its oscillation along tidal cycles revealed distinct patterns over the photoperiod in each season. A similar complex pattern was also observed for species richness, which showed distinct temporal patterns between high and low tides over the photoperiod in each season. Overall, shorter-term variations on fish assemblage attributes were correlated mainly with photoperiod and, to a lesser extent, tidal regime. Medium-term variations in fish abundance and species richness, in contrast, could result from seasonality in recruitment patterns and higher availability of allochthonous food resources during the wet period.

A re-assessment of the rocky sublittoral biota at Hilsea Point Rock in south Devon, UK was undertaken 50 years after the first descriptive surveys. The overall appearance of the fauna and flora in 2003 was much as described in the 1950s but with some species not re-found in 2003 and some species added to the lists from the 1950s.

The commensal (and possibly mutualistic) symbiosis between the marine chironomid, Halocladius variabilis, and brown algal epiphytes of Fucus vesiculosus and Ascophyllum nodosum is described for the first time from Europe, based on field studies from the White Sea, Russia. While the primary host, Elachista fucicola, and the secondary host, A. nodosum, are the same as in eastern Canada where the symbiosis was first described, White Sea populations have a wider range of primary hosts that include Pylaiella littoralis and Dictyosiphon foeniculaceus. About 64% of E. fucicola thalli on A. nodosum in the low intertidal zone were colonized. Significantly lower frequencies were found on E. fucicola when the latter was epiphytic on F. vesiculosus at the same tidal height or on either secondary host when they were in the subtidal zone. For a given tidal height, or secondary host, frequency of H. variabilis was reduced on P. littoralis and further reduced on D. foeniculaceus. We suggest that subtidal populations are colonized by dispersal of larvae from the intertidal zone on to suitable substrata, and that there is limited potential for these individuals to reach the intertidal zone as adults for reproduction.

A new species of Ampharetidae, Anobothrus amourouxi sp. nov., has been identified from bathyal depths of the Capbreton Canyon, Bay of Biscay (NE Atlantic Ocean). This new species is characterized by inner branchiae with transversal ciliated ridges, notochaetae from modified eighth thoracic unciniger with hirsute tips, uncini from thoracic unciniger with 6–7 teeth in lateral view arranged in two vertical rows in frontal view, fused segments II + III with paleae from SII and reduced notopodia without chaetae from SIII. An identification key for all hitherto described species of the genus Anobothrus is provided.

Television cameras and video equipment are well established as tools in many areas of marine research and have been reviewed by Barnes (1963), Myrberg (1973), Harris (1980), and Holme (1984, 1985). The TV camera is usually mounted on a remote sledge (Machan & Fedra, 1975; Holme & Barrett, 1977) or submersible, often with arrays of lights, and lacks the manoeuvrability that is necessary for many types of detailed survey and behavioural recording. Commercial and industrial uses also demand high-resolution equipment that is often contained in bulky underwater cases capable of operating at great depths and well below that possible by the conventional SCUBA diver. It is not unusual for the equipment to be used in conjunction with external lighting units where natural light levels are too low for the use of ambient light, and is dependent on an external power supply normally situated in the surface support vessel or within a submersible (Sisman, 1982).

A large, mature, female cirrate octopod, Cirroteuthis magna, was caught in a research trawl at 3200-m depth on the Cape Verde Terrace off the west African coast in November 1999. It is only the fourth recorded specimen of this species and the largest specimen (1,700 mm TL; 330 mm ML) of cirrate octopod ever caught. Detailed measurements were taken of the fresh and preserved specimen and indicated considerable shrinkage (17–32%) during formalin preservation. Careful dissection revealed large mature eggs (12·5–14 mm long) in the proximal oviduct, and a wide range of egg sizes and development stages in the ovary. The taxonomy and ecology of the species is briefly discussed.

The morphology and stomatogenesis of the marine scuticociliate Paranophrys magna, collected from a crab-culturing pond in Qingdao, China, were studied. It possessed typical characteristics of the genus Paranophrys. The stomatogenesis of this species corresponds basically with the results provided in previous studies for this genus, the main sequence develops can be generalized as follows according to the Qingdao population: (i) in the proter: the remnant of the parental paroral membrane generates the new paroral membrane and the scutica; and (ii) in the opisthe: both the paroral membrane and scutica originate from the proliferation of the anterior part of the secondary primordial field, membranelles 1&2 derive from the posterior part of the secondary primordial field, while membranelle 3 from the proliferation of the parental scutica which form the primary primordial field.  Some differences between our results and previous descriptions are compared and discussed.

Cirratulus tentaculatus is found inhabiting the wet, sandy, somewhat foul mud of the Aberystwyth shore, chiefly in the Laminarian zone, although it also occurs in rock pools higher up the shore in which there is sufficient depth of sand containing the necessary organic matter. The presence of the worm in its natural habitat is indicated by a group of delicate, elongate, rosy or yellow coloured filaments of tentacular appearance which protrude from the sand into the pools left by the receding tide. These filaments nearly always display a certain amount of movement, either waving gently from side to side or curling slightly from the tips. The amount of motion and also the colour of the filaments will depend on the degree of freshness of the water in the pool, and this, of course, will, in its turn, be related to the state of the tide.

Specimens are not easy to collect owing to the marked propensity the animal exhibits for lying with its body beneath stones or pieces of rock embedded in the mud. In rock pools or crevices where there is but little depth of sand and the animal lies with its body more or less parallel to the surface collection is almost impossible. This response to stimuli of contact and pressure, or, as M. Georges Bohn has it, this “thygmotactism,” is very marked, and, in the aquarium, when specimens are placed in a vessel containing sand and a few stones, the animals will roam about till some portion, at any rate, of their bodies is undergoing pressure from those stones.

Prionospio patagonica inhabits temporary silty tubes intertidally and shallow subtidally in brackish water estuarine environments in southern Chile. The species is gonochoristic with the female:male ratio being close to 2:1. Females and males release gametes into water. Pelagic planktotrophic larvae were caught in the plankton in the River Valdivia estuary in October–November and in March. Development of the adult morphology is described and illustrated beginning from the 2-chaetiger larval stage. One pair of lateral eyes first appears in the early larva, and shortly after that the right median eye develops. The left median eye appears after settlement, in juveniles with 10–11 segments. Developed 6-segment larvae have three dark red eyes, short palps of equal length, no nototrochs, one pair of small cells with grasping cilia on the pygidium, a small ciliated pit, gastrotrochs on segments 2–6, long serrated bristles in notopodia, adult capillaries in noto- and neuropodia on segments 2–5, single hooks in both rami on segment 6, and one pair of provisional papillae on the pygidium. A ventral buccal bulb is present below the short oesophagus and two pairs of provisional protonephridia are present in segments 1 and 2. The wall of the anterior part of the midgut has a characteristic brown pigment. The 6-segment larvae, about 400 μm long, settle and undergo gradual metamorphosis. In adults, hooks are gradually lost from noto- and neuropodia but sabre chaetae appear from segment 7 and retain their anterior position as growth proceeds. Up to 14 pairs of cirriform branchiae develop from segment 2, and three adult cirri appear on the pygidium. The afferent and efferent arms of each branchial blood loop are interconnected by capillary loops. A greenish heart body is present in the main dorsal blood vessel in anterior segments. Up to 21 pairs of metanephridia develop in anterior sterile segments, beginning with segment 4. Transparent gonoducts are present in fertile segments.

The relative importance of parental diet/population and larval diet were examined on egg, growth, morphology and biochemistry of Sclerasterias mollis larvae. Adult S. mollis were fed one cockle (Austrovenus stutchburyi) per two animals each week, as a low diet, or two cockles per animal each week, as a high diet. The experiment was run for one year. In addition, two field populations (Otago inshore and offshore) with dissimilar nutritional status (based on the gonad index) were selected. Otago inshore starfish had higher gonad indices and assumed to have better nutritional status. The low and high diet laboratory starfish produced eggs with similar characteristics. Eggs from the low diet laboratory parents had the highest carbohydrate concentration. The eggs from the field parents had higher fertilization rate and lower carbohydrate concentration than eggs from the laboratory parents. The Otago inshore starfish had smaller eggs with a lower carbohydrate concentration than the starfish from Otago offshore. Parents from the laboratory or the field had significant effects on larval growth, morphological phenotypic plasticity (measured by the body length relative to the body width) and development rate. Larvae from Otago offshore parents had highest growth and morphological phenotypic plasticity. Larvae from the low diet laboratory parents and those from Otago inshore had the highest development rate. Larvae from low diet laboratory parents had the highest carbohydrate concentration. Neither the parents nor the larval diet had a significant effect on larval mortality. A higher concentration planktonic diet resulted in higher growth, morphological phenotypic plasticity and development rate. Parents were however more important than larval diet on growth and phenotypic plasticity of the larvae. This study showed that parental nutrition has an important effect on growth, morphological phenotypic plasticity and body composition of S. mollis larvae. The nutritional status of the parents does not influence the larvae through a change in the egg size, protein, lipid, carbohydrate and energy content.

One hundred each of stage VI male and female and stage V Calanus finmarchicus were picked at random, and, by means of a projection microscope, measurements made on a number of segments in both metasome and urosome.

The stage VI female population was mixed containing 95% of a smallsized population and 5% of a larger size-group. The males constituted a single population.

At this time of the season the stage VI male and female metasomes are the same length, but there are differences in the sizes of the individual segments, the most striking of which is that of the head

The stage V animals in many of the measurements could be quite clearly separated into two size-groups of about 50% each and it is suggested that these are potential male and female populations. This separation at 50/50 has been noticed in numerous other collections of stage V, but it shouldbe emphasized that the differences are population differences in regard to those measurements considered.

Evidence is presented which shows that the state of the antennules after preservation in 5% neutral formalin is unlikely in stage V animals to be a reliable guide to their sex in the next stage.

Echinoderms are not generally considered to experience significant dilution of the surrounding medium in their usual marine habitats and so it is to be expected that, due to the absence of any obvious excretory organ, the ionic composition of the body fluid would be similar to that of the ambient sea water. In general this has been confirmed by previous workers for many species of echinoderm. Binyon (1966) lists the results of workers who have determined osmotic pressure and/or ionic concentrations in the perivisceral and/or ambulacral fluids of many echinoderms. With reference to the perivisceral fluid in asteroids there is usually a small excess of potassium (9–16%) which is maintained in the more euryhaline species and in those acclimatized to reduced salinity. Generally, the chloride content is similar to, or a little higher than, that in the surrounding sea water. In echinoids there is little difference in the potassium content and chloride concentrations with respect to sea water though there may be a small increase in the former ion. In the holothurians, there is little regulation of potassium ions. Such concentrations which have been determined for the chloride ion in this group are found to be a little higher than in sea water. The sodium concentration in the perivisceral fluids of echinoderms tends to be similar to, or slightly lower than, that in the surrounding sea water. However in the ambulacral fluids of the water vascular system it has been shown that the potassium concentration is 20–90% higher in some species of asteroids and echinoids (Robertson, 1949; Binyon, 1962,1966). The fluids of the water vascular system of echinoderms, analysed to date, have concentrations of sodium ions lower than in the ambient sea water. From the available evidence, there appears to be little difference between environmental and ambulacral chloride concentrations.