A new record of Crambionella stuhlmanni is reported from the east coast of South Africa. The material is described using quantitative morphological data, and mitochondrial (CO1) and nuclear (ITS-1) sequence data. The species can be diagnosed by a combination of morphological features including the presence of conical projections on velar lappets, the absence of orbicular appendages among mouthlets and the short length of the terminal club on the oral arm. Mitochondrial sequence data unambiguously delineate C. stuhlmanni as a separate species from C. orsini, and phylogenetic analyses support its placement within the monophyletic genus, Crambionella.

The diet of Haliclystus auricula was studied from the gut contents of Stauromedusae collected every two months in southern Chile between November 2001 and November 2002. A total of 3790 medusae were collected and examined. Stauromedusae prey consisted primarily of harpacticoid copepods (68·4%), followed by gammarid amphipods (15·4%), chironomid fly larvae (9·2%) and podocopid ostracods (5·9%). The remaining 1·1% of the diet was made up of empidid fly larvae, polychaete worms, isopods, juvenile decapod crustaceans and gastropods. Gut content was observed in 31% of the stauromedusae collected and only in medusae with an umbrella height greater than 0·4 mm. Frequency of medusae with prey items in their gut content increased with stauromedusae size. The type of prey most frequently found in the smallest medusae were copepods, whilst larger individuals contained mainly amphipods. A strong tendency for the length of prey consumed to increase with medusae size was found.

In the many references to Teredo from Plymouth early workers assumed that the common form was T. navalis L. Orton (1913) refers to this species, but he has recently told me that he did not try to identify the species precisely. It is almost certain that he was dealing with T. norvegica Spengler, which, it is now known, is the common large species in these waters. Harington (1922) ascribes the species with which he worked at Plymouth to T. norvegica, with a query, and no doubt he identified the species correctly. Yonge (1926) states that the Teredo with which he worked from the experimental raft near Plymouth Breakwater were probably all T. norvegica. Later he identified them as that species. Unlike T. navalis it does not carry its young in a brood pouch, but sends its eggs directly into the sea.

Three species have been found in recent years from the Plymouth district, two from the experimental raft moored near the Breakwater and from other fixed wood, and one from driftwood. The two commonly occurring from the raft are (1) T. norvegica and (2) a much smaller species carrying its young in a brood pouch, closely related to, if not identical with, T. navalis. The third species, occurring occasionally in driftwood, is T. megotara Forbes & Hanley. Purchon (1941), who worked at the last species from specimens in a tank at the Plymouth Laboratory, saw no sign of a brood pouch; and in those collected later from Wembury and examined by myself it was found that the eggs, shed directly into the sea, were very numerous.

The spionid polychaete Dipolydora armata, a borer in calcareous substrata, is recorded for the first time from Belize, Brazil, Taiwan, and Vietnam. Specimens from these and other localities, as well as the type material of Polydora armata from Madeira Island and Polydora rogeri from the Mediterranean were examined and all the specimens were considered to be conspecific. Dipolydora armata is up to 8 mm long (usually 2–3 mm), with up to 45 segments (usually 25–35 segments), an incised prostomium, caruncle until the end of segment 2, up to 10 pairs of branchiae from segment 7, up to 20 awl-like modified spines per notopodium in up to 15 posterior segments, bilobed or cup-shaped pygidium, hooded hooks from segment 7 accompanied by capillaries throughout the body, major falcate spines of segment 5 with a large lateral tooth and an apical structure covered by fine bristles and appearing as a cowling or third tooth on the convex side of the main fang.  The life history of the species includes a period of asexual reproduction by architomy beginning soon after settlement, then sexual maturation and continuous breeding within an extended period with production of lecithotrophic larvae developing entirely inside egg capsules. Once mature, individuals probably reproduce only sexually and do not undergo additional architomic divisions.  Asexual reproduction results in high morphological variability of adult individuals, particularly in number, size, and arrangement of awl-like spines in notopodia. Polydora rogeri is placed into synonymy of D. armata. The original interpretation of the relationship between the polychaetes and the excavating sponge Cliona viridis as mutualistic symbiosis is discussed. Dipolydora armata is considered to be a widespread non-specialized borer perforating various calcareous substrata.

The endangered patellid limpet Cymbula nigra is present in the extreme western Mediterranean, yet the species has rarely been the subject of study in this region. The aim of the present research is to describe the ecology, distribution and population structure of the species in an area of the Mediterranean coast of North Africa (Ceuta). Results indicate that the species prevails in waters that have an important Atlantic influence. Furthermore, different shell morphologies are distinguished, and in consequence, a statistical analysis is carried out based on morphometric data. Based on maximum shell length, height/length coefficients and shell morphology, a total of three significantly different morphologies are described. Furthermore, considering physical parameters such as height over seawater level and average substratum inclination, juveniles resulted to be clearly segregated from the two other groups. Additionally, no differences were found regarding the topography of the substrate used by juvenile and adult individuals, although the colonized surfaces are significantly smoother than those where Patella ferruginea is present.

Age and growth of adult gilthead seabream, Sparus aurata were determined from 332 specimens (total N = 476), collected from purse-seiners, in the south-eastern Aegean Sea from November 2006 to January 2007. The fork length and body wet weight ranged from 26.5 to 51.5 cm (mean: 36.6 ± 0.18) and from 375 to 2600 g (mean: 1009.2 ± 14.16), respectively. Age groups were varied between 2 and 7. Growth parameters were estimated as L∞ = 64.97 ± 12.93 cm, K = 0.14 ± 0.07 year−1, t0 = −2.47 ± 1.09 year−1, and index of phi-prime was Φ′ = 2.772 ± 0.51. The length–weight relationship equation of all fish was calculated as W = 0.0515 × L2.737 (r2 = 0.95). The mean condition factor was estimated as 2.058. Mortalities (M, F and Z) and exploitation rate (E) of gilthead seabream from the Aegean Sea were 0.34 year−1, 0.77 year−1, 1.11 year−1and 0.69 year−1, respectively. The result of E indicated that the population was overexploited.

Only one specimen of Architeuthis dux was previously reported from the southern Indian Ocean. The present work adds ten new records of giant squid in the area. Two remains of fresh specimens have been collected from La Réunion Island (21°S) and Amsterdam Island (38°S) in tropical and subtropical waters, respectively. Eight other squid were identified from beaks found in stomach contents of sleeper sharks caught in Kerguelen waters (47 to 48°S) located in the southern Polar Frontal Zone. These new data together with published and unpublished information on the food of seabirds and marine mammals indicate that giant squid have a wide distribution throughout the southern Indian Ocean.

In the whiting, no significant changes occur in the composition of the muscle substance, either throughout the year, or with increasing age, or during ripening of the gonads.

The amount of fat in the liver is very low in immature fishes, increasing greatly with age, and reaching its maximum just after the commencement of the ripening of the gonads. It then falls off, reaching its lowest value amongst mature fishes in the “Spent” stages. Males are richer in liver fat than females.

Immature fish have a decidedly higher protein content in the liver than have mature fish.

The distribution and bathymetric zonation of deep-sea ophiuroids off the Japanese Pacific coast were analysed. Samples were collected using beam trawls between depths of 60 and 6382 m. In 154 samples, 139 ophiuroid species were found. Data were clustered based on Morisita–Horn similarity index and a dendrogram was constructed. The Japanese Pacific coast can be divided in two major zones. One in the northern part off the Japanese Pacific coast, and another in the region off the central Japanese Pacific coast. In the northern region, five bathymetrical zones were detected at depths of 130–250, 300–500, 500–650, 1100–1500, and 2000–3000 m. In the central region, eight bathymetrical zones were detected at 100–140, 150–250, 200–300, 220–300, 300–400, 400–500, 800–1000, and 1000–1500 m depth. Representative species for each bathymetrical zone are reported.

Many didemnid ascidians have calcareous spicules in the tunic. Since the spicules of each species have a specific shape and size-range, they are often regarded as an important character for taxonomy. To evaluate the taxonomic significance of tunic spicules, a quantitative survey of spicule size and shape was combined with a molecular phylogeny inferred from the partial sequence of the cytochrome c oxidase subunit I (COI) gene in some groups of didemnid species that are supposedly closely related. This study revealed the presence of substantial intraspecific variations in the shape and size of tunic spicules. The spicules are, therefore, not always crucial features discriminating species, particularly among related species. Although tunic spicules are potentially valuable features for didemnid taxonomy, their intraspecific variation should be carefully considered before they are used as a key character for species identification.

The alien blue swimming crab, Portunus segnis (Forskål, 1775), an Indo-Pacific species, has been recorded in the southern Mediterranean Sea for decades, and its occurrence along the southern Tunisian coasts has been recorded since 2014. The feeding habits of P. segnis were studied in the Gulf of Gabes from October 2015 to September 2016. The stomach contents of 3061 crabs, ranging from 50 to 168 mm carapace width, were analysed. The stomach contents appeared to consist mainly of large quantities of crustaceans, fish and molluscs, and small quantities of echinoderms, annelids, tunicates, cnidarians, plants, unidentifiable matter and debris. The major food groups observed were crustaceans throughout the year with fish and molluscs secondly. In juvenile, sub-adult and adult crabs, crustaceans constituted the dominant food source and these were present in more than 65% of the stomachs analysed. Ingestion of fish increases as the crab matures. A significant difference (P < 0.05) was observed in the quantity of the food consumed by the two sexes. The diet also increased with increasing ovary maturity degree, while the percentage of empty stomachs in ovigerous and non-ovigerous females did not show any difference. The vacuity index varied significantly in both sex (P < 0.0001), among size (P < 0.0001) and seasons (P < 0.0001). This study shows that, despite the diversity in blue crab diets and feeding habits, it is omnivorous with a preference for animal material.

The genus Achirus is made up of demersal fish that have a close relationship with the substrate and exhibit peculiar aspects during their larval stage. The aim of the present study was to determine whether the abundance of Achirus larvae differed among a set of habitats in the estuary of the Formoso River in the State of Pernambuco (north-eastern Brazil). Sampling was performed monthly between April 2009 and March 2010, and comprised horizontal hauls with plankton net during the day and night in mangrove, beach and reef habitats. Fish larvae were sorted, identified, measured and larval stage recorded. Density and body length values were used in a non-parametric analysis of variance for the determination of variations between seasons, habitats and diel periods. A total of 204 larvae were collected, with an average density of 2.1 larvae.100 m−3. Density was greater in the nocturnal samplings, with no differences found between habitats. The larvae occurred in the yolk-sac to post-flexion stage, with pre-flexion the most abundant stage (78%). Size segregation was observed. Larger larvae were captured at night and in the mangrove. The smallest larvae were caught on the reef, with length increasing toward the mangrove. The results indicate that Achirus larvae come from deeper regions near reefs, where spawning probably occurs, and perform ontogenetic migration towards the shallow waters of mangrove, where they settle.

As two pigmented taxa attributed to the class Chrysophyceae had been discovered (Lackey, 1939; Scagel & Stein, 1961) with apparently similar organization to the Choanoflagellida this group of protista was included in the Revised Check-list of British Marine Algae (Parke & Dixon, 1964) following Bourrelly (1957). The group was placed in the class Craspedophyceae erected by Chadefaud (1960) and a first revision of the genus and species list was included in the Check-list of British Marine Algae - Second Revision (Parke & Dixon, 1968).

This study reports on the seasonal variations of the community structure of a coastal ecosystem, off the central coast of Brazil. Samples were collected on a monthly basis on board a bottom otter trawl vessel from October 2003 to September 2004. A total of 57 species belonging to 26 families and 10 orders were collected. Resident species, which presented a high proportion of juveniles throughout the year, were the most abundant. Among these, benthonic fish of the Sciaenidae family were the dominant species, followed by Tetraodontiformes, nektonic Sciaenidae and Clupeiformes. Benthonic fish were more abundant during the spring/summer months (October to February) and pelagic species dominated the autumn/winter months (May to September). However, these differences were not statistically significant. The spring/summer months were also characterized by reproduction activity, while the autumn/winter months saw high proportions of juveniles. Indicator species analyses showed that 5 species presented significant differences in their occurrence and abundance throughout the seasons of the year. This study shows that the coastal area is an important place for reproduction and a nursing ground of many species. It also shows evidence of community-level reproductive patterns for a tropical ecosystem. Future studies are necessary to identify the likely ecosystem forcings underlying these patterns.

The aim of the present study was to characterize the external morphology and the orientation of burrows constructed by the mangrove crab Ucides cordatus. Data were obtained from two mangrove forests of similar vegetation dominance (Laguncularia racemosa) but differing in flooding heights. These mangroves were located near Barra de Icapara, Iguape City (SP), Brazil, (24°50′36″S–47°59′53′W). A total of 221 burrows were examined (120 on the high mangrove and 101 on the low mangrove). External morphology of the burrows was recorded by photographs for categorization and description. The directions of the burrow openings were recorded using a geological compass and the declivities of the ducts were measured with a clinometer. Females constructed 70.8% at Site A and 69.4% at Site B of the occupied burrows with the opening facing the margin of the river (P < 0.001), whilst males showed no significant difference in the burrow orientation (P > 0.05) at either site. In females, the tendency for burrow orientation possibly has a reproductive connotation as larval dispersal may be favoured and enhanced by the tides. Four groups of distinct tracks related to the morphotypes and developmental stages of U. cordatus were observed. No sediment constructions associated with the burrows were recorded for this species. Declivity of the burrows from juveniles was lower than from adults (P < 0.05), probably caused by the differential growth of the chelipeds in this species.

Seasonal changes in altimeter data are derived for the North Atlantic Ocean. Altimeter data are then used to examine annually propagating structure along 26°N. By averaging the altimeter data into monthly values or by Fourier analysis, a positive anomaly can be followed from 17°W to ∼50°W along ∼26°N. The methods give a westward travel speed of 1° of longitude a month and a half-life of one year for the average decaying structure. At ∼50°W 26°N, the average structure is about 2·8 years old with an elevation signal of ∼1 cm, having travelled ∼3300 km westward. The mean positive anomaly results from the formation of anticyclonic eddies which are generally formed annually south of the Canary Islands by late summer and which then travel westward near 26°N. Individual eddy structure along 26°N is examined and related to in situ measurements and anomalies in the annual seasonal concentration cycle of SeaWiFS chlorophyll-a.

An experiment was carried out to estimate the rate of indirect fishing mortality on juvenile Spisula solida due to the exposure time on deck. Samples were collected using a dredge from a site off Vilamoura, south coast of Portugal, during July 1994. Length of deck exposure is directly related to mortality of juveniles. It was estimated a fishing mortality rate of 0.00335 per min, due to length of exposure.

In this study we revise the current knowledge on the biodiversity and distribution of the Class Homoscleromorpha in the Tropical Western Atlantic (TWA). Twenty-seven species are currently recognized in the TWA, belonging to the genera Oscarella (O. nathaliae), Plakortis (P. angulospiculatus, P. dariae, P. edwardsi, P. halichondrioides, P. insularis, P. microrhabdifera, P. myrae, P. petrupaulensis, P. potiguarensis, P. simplex, P. spinalis, P. zyggompha), Plakinastrella (P. globularis, P. microspiculifera, P. onkodes, P. stinapa), Plakina (P. coerulea, P. elisa, P. jamaicensis, P. monolopha, P. tetralopha, P. trilopha, P. versatilis), Corticium (C. diamantense, C. quadripartitum) and Tetralophophora (T. mesoamericana). Three of these ‘species’ are cosmopolitan and in fact represent complexes of cryptic species: Plakina monolopha, P. trilopha and Plakortis simplex. All other 24 species reported are TWA endemics. Only four species are found both in the Caribbean and in Brazil: Plakortis angulospiculatus, P. halichondrioides, Plakinastrella microspiculifera and P. onkodes, but these may also be species complexes. Seven species are Brazilian endemics: Plakina coerulea, Plakinastrella globularis, Plakortis insularis, P. microrhabdifera, P. petrupaulensis, P. potiguarensis and P. spinalis. Thirteen species are restricted to the Tropical North-western Atlantic: Corticium diamantense, C. quadripartitum, Oscarella nathaliae, Plakina elisa, P. jamaicensis, P. tetralopha, P. versatilis, Plakortis dariae, P. edwardsi, P. myrae, P. zyggompha, Plakinastrella stinapa and Tetralophophora mesoamericana. The Greater Antilles is the richest ecoregion, with 12 species reported. Only the Guianan ecoregion has no records of Homoscleromorpha. Several undescribed species of Oscarella and Plakina are also known from the TWA. We estimate that the biodiversity of Homoscleromorpha in the TWA is at least twice as high than currently known.

Cardiac activity of two White Sea Bivalvia species – Mytilus edulis and Modiolus modiolus – was monitored in situ for one full calendar year every 4 days. During the year, we also assessed the temperature and salinity of the ambient seawater (at intervals of 1 min), measured phytoplankton concentration (every 4 days) and checked the reproductive status of the molluscs (every 2 weeks). Our field study showed a significant linear correlation between the molluscs’ heart rates and the temperature of the ambient seawater. However, during specific periods of the year, we observed that phytoplankton composition or reproductive status became the dominant influence over cardiac activity. Phytoplankton concentrations were generally found to be low throughout the entire year, but two peak periods of drastically elevated phytoplankton concentration were found (April and May), and during April the peak heart rates of the blue mussels significantly increased. Spawning time took place in the middle of June, and at this time the cardiac activity of the molluscs did not change in spite of a 4°C temperature increase in the ambient seawater. Monitoring of the heart rates of the real intertidal blue mussels (animals located at the middle part of intertidal) revealed periodic fluctuations in cardiac activity that correlated strongly with tidal fluctuations. Cardiac activity in M. modiolus was significantly lower than in M. edulis from 9 May to 25 November. On the basis of our data, we concluded that the molluscs’ cardiac activity can serve not only as an indicator of the animals’ physiological conditions, but also as an indicator of changes in ambient factors.

The dry weights, carbon and nitrogen content of fresh dried Calanus spp. Pseudocalanus elongatus, Acartia clausi, Temora longicornis, Mesocalanus teniricornis, Metridia lucens and Candacia armata were determined from samples taken in the southern North Sea, the English Channel, the Irish Sea and the Celtic Sea in December 1984 and February 1987. Usually adult females were picked out but some data were obtained for adult males and copepodites of Calanus spp. and T. longicornis and male M. tenuicornis. Significant differences were found between stations on the same cruise in the results for adult females of the same species. The weights of Calanus spp. females in February 1987 were found to be inversely related to temperature.