The trophic composition of macrobenthic communities in intertidal and subtidal soft-bottoms of the Ensenada de San Simón (north-western Spain) was found to be related to a number of environmental variables. Distribution and abundance of trophic groups have been studied, to provide essential baseline information for monitoring the area, after its designation as a Natura 2000 Special Conservation Zone. Analyses of trophic data showed a numerical predominance of the herbivores in the inner part of the inlet, while sites at the oceanic-influenced area were numerically dominated by surface-deposit feeders. These dominances were mainly due to Hydrobia ulvae in the intertidal area and to polychaetes at the subtidal one. Both univariate and multivariate statistical analyses showed that the sediment composition (organic matter and silt–clay contents) and temperature of the bottom water influenced the benthic macrofauna and were correlated with their trophic composition, abundance and distribution.

The cirri of the digital tentacles of Nautilus pompilius are covered by annular ridges, more pronounced on the oral (adhesive) than the aboral side. On the oral side the epithelium is thicker on the proximal and outer surfaces of the ridges than on their distal surfaces. Prominent electron-dense granules occur in the cells of the thick epithelium, but are absent from the thin epithelium and the epithelium of the aboral surface. These granules contain mucopolysaccharide and may be responsible for adhesion.

The digital tentacles of Nautilus are used for attachment to, for example, prey, the substratum, or the partner's shell during mating. Their general structure and histology have been described by Owen (1832), Willey (1898), Barber & Wright (1969), Fukuda (1987) and Kier (1987). The mechanism of adhesion is still uncertain. Barber & Wright (1969) report epithelial cells of two types: pigmented cells containing pigment granules 0–5–1 µm in diameter, interspersed with a small number of mucus-producing cells which may help with the adhesive process.

The Zoea of Eurynome aspera has already been twice described—namely, by Kinahan (1857) and Cano (1893), but there is some discrepancy between the two accounts which an observation made at Plymouth in April, 1922, fully explains.

Kinahan observed the larva immediately on hatching and described it as having neither rostrum nor dorsal spine; whereas Cano describes it as having both.

Records of beaked whales stranded in the Falkland Islands and at South Georgia were collated for the period 1866 to 2008. Thirty-eight records, involving at least seven species in four genera, were documented. Strap-toothed whales (Mesoplodon layardii Gray, 1865) were the most common species with 11 records, including two neonates. Andrews' beaked whales (M. bowdoini Andrews, 1908), Arnoux's beaked whales (Berardius arnuxii Duvernoy, 1851), Cuvier's beaked whales (Ziphius cavirostris Gray, 1823), Gray's beaked whale (M. grayi van Haast, 1876), Hector's beaked whales (M. hectori Gray, 1871) and southern bottlenose whales (Hyperoodon planifrons Flower, 1882) were recorded on three to five occasions. In several cases, records suggested potential temporal changes in range. For example, Arnoux's beaked whale has not been recorded in the Falkland Islands since 1965, whilst Gray's beaked whale was not recorded prior to 1981, and Andrews' beaked whale was not recorded before 1987. Although the number of records for each species is low, this could reflect changes in water temperatures and/or prey availability. Overall, this study confirms that the Falkland Islands–Tierra del Fuego region is one of the world's key areas for beaked whales.

Sea turtles are partners in commensal relationships with a variety of epibionts, including barnacles. The acorn barnacle Chelonibia testudinaria is one species commonly found associated with sea turtles and other marine fauna throughout temperate to tropical waters including the Indo-Pacific. We conducted a study to assess the occurrence of this barnacle, relative to host life stage and species in a mixed foraging population of green (Chelonia mydas) and hawksbill (Eretmochelys imbricata) turtles (juvenile, sub-adult, adults (female and male)) in Mabul Island, Sabah, Malaysia (Celebes Sea). Expecting similar relative abundance by life stage, we found instead a significant effect between the combined dependent variables (abundance and size of barnacles) and the life stages of sea turtles in Mabul after controlling for the covariates of size and species of sea turtles (F(8, 428) = 5.77, P < 0.001, Pillai = 0.19). Among green turtles with barnacles, though adult males had larger barnacles compared with the female turtles, the mean barnacle abundance on adult females (43.4 individuals ± 5.19 SD) was higher than all other life stages. Most of the barnacles (85.6%; N = 1931) were found on the plastron of the sea turtles. The highest number of barnacle reacquisition was found among the juvenile turtles. In assessing the complemental males of the barnacles, we found they were consistently attached to the shells of the larger of the hermaphrodites from each region of the host's body despite average shell-size differences with each region.

In this research, we compared the anatomy and biomechanics of two species of mudskipper vs an aquatic sandgoby in view of terrestrial locomotion. Of particular interest was the relationship (if any) of pectoral fin movement with pelvic fin movement. We show that the pelvic fins of the terrestrial mudskippers studied herein, are retractable and move antagonistically with the pectoral fins. The pelvic fin of the sandgoby studied here is contrarily non-retractable and drags on any underlying substrate that the sandgoby tries to crawl across. We find that the pelvic and pectoral fin muscles of all fish are separated, but that the pectoral fins of the mudskipper species have bulkier radial muscles than the sandgoby. By coupling a detailed morphological investigation of pectoral-pelvic fins musculature with finite element simulations, we find that unlike sandgobies, the mudskipper species are able to mechanically push the pelvic fins downward as pectoral fins retract. This allows for an instant movement of pelvic fins during the pectoral fin backward stroke and as such the pelvic fins stabilize mudskippers through Stefan attachment of their pelvic fins. This mechanism seems to be efficient and energy saving and we hypothesize that the piston-like action might benefit pelvic–pectoral fin antagonism by facilitating a mechanical down-thrust. Our research on the biomechanics of tree-climbing fish provides ideas and greater potential for the development of energetically more efficient systems of ambulation in biomimetic robots.

In a communication to the Royal Society (Phil. Trans. vol. clxxxiv. 1894, and in this Journal, vol. ii. no. 1), I described a series of experiments in which light was directed upon the lower sides of flat fishes, by means of a tank with a glass bottom, and a mirror placed beneath it. I have now to record an observation which confirms my previous results in a most striking manner. Curiously enough, the effect I am about to describe, in some respects even more important as evidence than those obtained in my experiments, was observed accidentally, or at least incidentally, and was due to conditions which had been quite unintentionally produced.

INTRODUCTION

In 1976 the Fisheries Laboratory, Lowestoft, carried out 13 plankton sampling cruises off the north-east coast of England. They spanned the months February-November. From these cruises Harding et al. (1978) described the distributions of surface chlorophyll and nutrients and the production offish eggs and larvae. Reynolds (1978) described in more detail the distributions of chlorophyll and phaeopigments throughout the year, and Horwood (1982) detailed the distribution of zooplankton biomass. This study presents the species composition of the algae from a small region of the survey area illustrated in Fig. 1.

0-group bass were sampled from the shallow creeks of the Tamar and Camel estuaries at regular intervals from May to September in 1981 to 2000 to measure relative year-class abundance. From 1989 onwards classes were generally strong, especially those of 1989, 1992 (Tamar only), 1995 and 1998. Sampling at age-4, before departure from the nursery at the onset of adolescent movements, gave broadly similar relativities. Numbers were greater, and growth faster, in the Tamar than in the smaller and cooler Camel. Temperature was an important factor in both abundance and growth. Occasional major differences in abundance between the two estuaries were reported. Factors which might bias the age-4 result are considered. Other estuaries on the south side of the south-west peninsula, sampled less frequently, reflected Tamar abundances; others on the north side reflected Camel abundances. Limited analysis of stomach contents of older juvenile bass often present in the same habitats revealed no evidence of cannibalism on 0-groups. The shallow creeks of the Tamar and Camel were deserted in winter but a deeper creek on the Taw, frequented throughout winter, was sampled monthly in the 1982–1996 winters to measure losses, if any, in cold periods. In the mainly mild winters, losses were infrequent and small except in the five-week cold spell of early 1986, when the 1985 class suffered an estimated 58% loss in the Taw and possible total loss in the Camel and the Tamar. Sudden heavy flooding of the estuaries caused no apparent losses when they occurred in late summer and autumn but might be damaging if they occur soon after post-larvae arrive.

The prey size of young cuttlefish was investigated by measuring the size of entire animals, carapace, periopods, and otoliths in the stomach contents of specimens from Morbihan Bay in 1994–1996. The young of the Sepia species consumed a wide range of prey sizes. The size of all isopods and amphipods was less than the 50% of those of the Sepia. The size ratio of brachyurans varied between 14 and 37% of the dorsal mantle length of the cuttlefish. The young could catch fish species which were three times larger than itself.

The vertical distribution, morphology and diet of Proboscidactyla stellata (Cnidaria: Limnomedusae) were studied in Lough Hyne over a two year period. Vertical hauls of four depth strata, 40–30 m, 30–20 m, 20–10 m and 10–0 m, were taken monthly and at 4 h intervals for a period of 48 h in July and 24 h in September 1994. Proboscidactyla stellata was largely concentrated in the lower 20 m of the water column reaching a maximum of 21 m−3 at 30–20 m depth in June 1993. An oxythermocline occurred at 25–30 m depth in the summer and autumn months of 1993 and affected the vertical distribution of the medusae. Six morphs of the species, varying in the number of gonads, were found in the lough. Bivalve veligers, which P. stellata actively selected, formed 83% of the diet.

In the third paper about Ampharetidae from Japan, we describe six species that belong to the ‘Amphicteis genus complex’. We divide this complex into the genera Amphicteis Grube, 1850, Paramphicteis Caullery, 1944, Phyllamphicteis Augener, 1918 and Watatsumi gen. nov. Paramphicteis is considered senior synonym of Pseudoamphicteis Hutchings, 1977 and is characterized by pinnate buccal tentacles. Watatsumi gen. nov. with its type species Watatsumi grubei sp. nov. is characterized by the lack of prostomial glandular ridges, the presence of pinnate buccal tentacles, and inconspicuous nuchal ridges. Two of the Amphicteis species are new to science, including A. spinosa sp. nov. and A. taurus sp. nov. Paramphicteis weberi (Caullery, 1944) comb. nov. was transferred from Amphicteis because we found pinnate buccal tentacles in addition to four pairs of foliose branchiae. Paramphicteis foliata (Haswell, 1883) comb. nov. was transferred from Phyllamphicteis because it has pinnate buccal tentacles. Amphicteis uncopalea Chamberlin, 1919 and Paramphicteis angustifolia (Grube, 1878) are newly recorded from Japanese waters. Amphicteis orphnius Chamberlin, 1919 is considered senior synonym of A. obscurior Chamberlin, 1919. A comprehensive table with diagnostic characters of all species of the Amphicteis complex with pinnate buccal tentacles is provided.

Recent observations of unusual mass stranding and mortality of two Indian Ocean crustacean species, the swimming crab Charybdis smithii and the mantis shrimp Natosquilla investigatoris, are documented and analysed. Strandings of C. smithii were observed for the first time in the equatorial Indian Ocean, the main area of its pelagic distribution. Strandings of mantis shrimps are reported from throughout the western Indian Ocean; occurrences of mass stranding in the Maldives Archipelago mark an extension of the known range of N. investigatoris into the central Indian Ocean. Mortality of crabs probably represents a ‘catastrophic event’. In contrast, mantis shrimp strandings, which were always associated with a sudden increase of its biomass (‘blooms’), are apparently post-reproduction mortalities indicating potential semelparity for this species.

Skulls of 153 porpoises from the Sea of Azov and the Black Sea were studied. Thirty-seven skull measurements were examined. Skull growth in porpoises can be divided into five periods. The greatest changes in growth patterns occur after the first weeks of life. A ‘relay effect’ in growth of some structures (e.g. rostrum) was observed. Individual variation usually increases when a given structure grows intensively; however, some structures are highly variable over the entire lifespan. Sexual dimorphism is demonstrated in most of the measurements in adult animals. Temporal variation is minor. Skull structures are characterized by six types of allometry; three of them demonstrate drastic changes of allometry during lifespan, thus requiring two allometric equations to describe them. Skull proportions change critically during the first weeks of life. Six groups of correlated measurements differing in the pattern of correlation links during ontogeny were identified. Three factors play the most important roles in forming the definitive skull proportions: correlation between adjacent structures, impact of total skull size and inclusion in a certain functional complex.

Amiantis purpurata shells from the San Matías Gulf (SMG) were analysed in order to compare both morphology and size throughout the late Quaternary in relation to environmental changes. Shells from modern beaches, Holocene marine assemblages (late Holocene, 3630 ± 100 years bp) and interglacial Pleistocene marine assemblages (MIS 5, 100 ka years bp) were studied by measuring the height and length, and using the elliptic Fourier analysis (EFA) to take an outline contour. The Pleistocene shells were smaller, more elliptical and with a deeper lunule than the Holocene and modern ones. No significant differences were recorded in the allometry index throughout the late Quaternary. The variation in size and shape of the A. purpurata shells could be related to the phenotypic plasticity of this species as a response to the environmental changes registered in the SMG during the Quaternary. These changes include variations in sea surface temperatures, salinities and substrates, and also water circulation changes, which would have modified nutrient availability. Morphological changes imply burrowing activity, mechanical stability, nutrient uptake and defence response to predation.

‘Pliocardia' krylovata, sp. nov. (Bivalvia: Vesicomyidae: Pliocardiinae) is described from cold seeps off the coast of the Nicoya Peninsula, Costa Rica (700–1000 m depth). The phylogenetic position of ‘P.' krylovata was assessed by both morphological comparisons as well as nucleotide data from the cytochrome c oxidase I gene. Within the vesicomyids, ‘P.' krylovata belongs to the Pliocardiinae and its closest relative is ‘Calyptogena' ponderosa, which also bears some morphological resemblance to the genus Pliocardia, perhaps suggesting a need for reanalysis of not only its generic designation, but also the entire Pliocardiinae subfamily. ‘P.' krylovata has morphological similarities to ‘Pliocardia' bowdeniana and ‘Vesicomya' crenulomarginata, recently reassigned to the genus Pliocardia, including a thick shell, obvious rostrum, pointed posterior end, and a sculptured shell with concentric ribs on the outer surface, to name a few. It is morphologically distinguished, however, by having a complex pallial sinus and remarkably deep escutcheon.

Pacifigorgia marviva, a new shallow-water species of the family Gorgoniidae, was found in Coiba National Park, Pacific Panama at 35–40 m depth. It is characterized by having white to cream, small, erect colonies composed of 1–4 fronds, stems short or absent network irregular and open without fan midribs, and polyp mounds slightly raised and sparsely distributed. All sclerites are colourless. Coenenchymal sclerites mostly composed of long spindles reaching up to 0.25 mm in length, and long and thin anthocodial rods, up to 0.16 mm in length. Morphological characters are analysed and illustrated. Scanning electron microscopy was used for sclerite study. The new species is herein described and compared with other similar species reported from the eastern Pacific. Pacifigoria marviva increases the number of Pacifigorgia species to 35; 20 in Panama representing 57% of the genus in the eastern Pacific, followed by Costa Rica and Ecuador with 14 and 10 species, respectively.

This paper focuses on Diplolaimella and Diplolaimelloides two very cosmopolitan genera inhabiting lotic freshwater to salty water inland, groundwater and coastal waters systems, providing a review of their taxonomy with new keys, and their distribution on the east coast of Patagonia and inland Patagonia. Two new species belonging to the genus Diplolaimelloides of the family Monhysteridae are described from Patagonian salty lagoons and coastal areas, and the Chubut and Santa Cruz provinces of Argentina: Diplolaimelloides tehuelchus sp. nov. has four bursal and three postcloacal papillae, short gubernaculum, and spicules longer than 50 μm; it has been found in Patagonian salty lagoons and in high coastal salt marsh areas. Diplolaimelloides warwicki sp. nov. is characterized by the angular shape of the spicules and the long gubernaculum. Diplolaimella ocellata is recorded for the first time in Patagonian salty lagoons and new localities in coastal waters are recorded for Diplolaimella gerlachi Pastor de Ward, 1984.

A potential new species of Barracuda Sphyraena intermedia sp. nov. (Perciformes: Actinopterygii) is reported from the Gulf of Taranto in the central Mediterranean Sea. This classification was based upon a thorough anatomical comparison with well documented species from the region (Sphyraena sphyraena and Sphyraena viridensis). Principally, Sphyraena intermedia sp. nov. differed from the other species within the genus in terms of body shape, otoliths, dentition and pyloric caeca.

Harpacticoid copepods (Crustacea) comprise an important taxon of the sedimentdwelling meiofauna, generally being numerically inferior to only the Nematoda (Hulings & Gray, 1971). This paper reports those species comprising the fauna of the sediments of the River Ythan estuary, particularly the intertidal sediments, and describes some of the properties of the meiobenthic copepod community structure.