Reproduction and feeding of Argentina sphyraena L. were investigated during a study of the biology of this species in the Clyde Sea Area of Western Scotland from 1963 to 1966.

Morphometric characteristics and spatial distribution of Tontonia grandis sp. nov. were investigated in the northern East China Sea and the adjacent sea areas. Tontonia grandis has a large conical body shape, 113 μm (70–155 μm) in length by 55 μm (40–113 μm) in width, a caudal appendix, multiple macronuclei and 14 (13–16) anterior and 28 (24–33) ventral polykinetids. Some cells have numerous cortical platelets on the surface and others do not. These two forms showed different horizontal distribution, and hence the presence of cortical platelets might be influenced by the environment inhabited. However, various forms of caudal appendix were observed, which constitute a continuous series of their developmental stages. This result might suggest that the caudal appendix is replaced by new growth and repeats its developing and sloughing spontaneously.

Microphytobenthos need photoadaptive strategies to survive the highly dynamic light environment in which they reside. Xanthophyll pigments can provide photoprotection by cycling electrons between epoxide and de-epoxide forms, dissipating excess light energy as heat. This study examined the xanthophyll cycle in microphytobenthos on a tidally exposed substrate at Browns River, Tasmania. Fv/Fm decreased from 0.52±0.01 to 0.47±0.01 at noon in surface samples and a decrease in the diadinoxanthin:chlorophyll-a ratio from 0.022±0.003 to 0.015±0.005 also suggests that the microphytobenthos was under physiological stress at noon. The results indicate that the cells exposed to light at the surface migrated deeper into the sediments and replenished the epoxide form of their xanthophylls. The results suggest that micrphytobenthos utilizes both behavioural and physiological strategies to survive in the dynamic intertidal environment.

Three deep-water species of the north-eastern Atlantic have been studied: Caryophyllia abyssorum Duncan, 1873, C. calveri Duncan, 1873, C. sarsiae n.sp. Of these only C. abyssorum has not been found in the Mediterranean. In the north-eastern Atlantic these species appear characteristic of somewhat different depths, but occasionally can be found together. Obtained by early deep-sea expeditions (“Porcupine” cruise of 1870, cruises of Prince Albert I of Monaco), all three species have been previously confused and assigned, chiefly, to the little-known fossil species C. arcuata and C. cylindracea. In order to show the world-wide confusion about C. arcuata, some other records, from Cape Verde Islands to Japan through Antarctica, are quoted.

The survivorship of marine invertebrates that have a life span of less than 2 years is usually assessed by observing the decrease in abundance of animals from samples taken frequently throughout the life of an identifiable cohort or generation (e.g. Crisp, 1971). This method is only suitable for species with approximately simultaneous recruitment so that the animals can be aged with reasonable accuracy and the mortality before the end of the recruitment period can safely be ignored. Such age-specific survivorship data can be used to calculate secondary production by revealing the number of animals that reach successive weights (= Allen curves) (Crisp, 1971).

In the Forth Estuary, Scotland, parasitic rhizocephalan barnacle Sacculina carcini externae or scars occurred on 64% of Carcinus maenas from the subtidal channel of the middle estuary. These became more frequent downstream, infecting 46·9% in the lower estuary basin. Male and female crabs were infected equally, and infection rates in low-tide samples did not differ from high-tide. The parasites occurred most frequently on crabs of 40–50 mm carapace width (CW) rather than the modal crab size class of 50–60 mm. Downstream, proportionately more smaller than larger crabs bore parasites whereas, further upstream, more larger than smaller crabs bore parasites. There is evidence for the annual appearance of new externae in July-October, especially in the lower estuary basin, followed by their growth and loss after about a year.

Myrianida pinnigera (Montagu) is one of the representative Syllids in the Plymouth district. Here, it is found always in close association with Ascidiella aspersa and Phallusia mammillata, possibly feeding upon the body fluid of these Ascidians.

The present work on the feeding ecology of Scorpaena porcus according to season, sex and size, is the first study carried out in the rocky intertidal in the NE Atlantic. Previous studies were carried out with fish collected in fishing grounds from Mediterranean areas. A total of 106 fish were caught in monthly samplings from April 2008 to July 2010 in three areas of the rocky intertidal zone in the Gulf of Cadiz. The diet composition varied with season, size and sex. Shrimps were the main diet resource during all year, but other prey were also important depending on the season. As the size of fish increased, predation on smaller crustaceans decreased and consumption of larger crustaceans and fish augmented. Females and males based their diet on shrimps, while indeterminate fish fed largely on amphipods. No significant differences were found between feeding intensity and season, size and sex. Nevertheless, the PERMANOVA results showed that the number of prey is affected by the interaction between sex and size class. Our results highlight that S. porcus is a stenophagic species that shows a gradual segregation in the use of resources as it grows, which indicates there is no intraspecific competition in the rocky intertidal.

New values for the extinction coefficient of red light in distilled water require that published results for this coefficient in waters from the Tamar Estuary shall be increased by o.1, 1.3 and 2.0 at 610, 720 and 750 mμ respectively. Earlier deductions as to the favourable transmission of red light in turbid estuarine waters apply only up to about 680 mμ. That part of the extinction coefficient due to suspensoids and colouring matter was inversely proportional to the first power of the wave-length. Other conclusions remain unaffected.

Paramya is an enigmatic genus of Myidae (Bivalvia: Heterodonta: Myoidea) that includes three uncommon species: Paramya subovata (Conrad, 1845), Paramya recluzi (A. Adams, 1864) and Paramya africana Cosel, 1995. Paramya subovata is known as a commensal living in the burrow of the spoon worm Thalassema hartmani Fisher, 1947 (Annelida: Echiura: Thalassematidae), in North American coastal waters. However, the biology of the other two species remains unknown. In this study, we found P. recluzi living in the burrows of the two thalassematid echiuran species, Ikedosoma gogoshimense (Ikeda, 1904) and Arhynchite hayaoi Tanaka & Nishikawa, 2013, in intertidal flats in the Seto Inland Sea, Japan. Paramya recluzi was embedded in the burrow wall with its short siphons protruding into the host burrow lumen for respiration and filter feeding. To determine the phylogenetic position of P. recluzi, we performed a molecular phylogenetic analysis using the 18S, 28S, COI and H3 genes. Molecular analysis showed that P. recluzi belongs not to the family Myidae, but to the genus Basterotia (Galeommatoidea: Basterotiidae). Morphological examination of P. recluzi revealed that this species has many similarities with Basterotia (e.g. a single cardinal tooth on each valve and short siphons surrounded by tentacles). Thus, we propose that this species should be transferred from the genus Paramya to Basterotia. In addition, we also suggest that the other two species of Paramya (P. subovata and P. africana) should be transferred to the family Basterotiidae based on their shell morphology, anatomy and ecological characteristics.

This study aimed to describe the ethnoecology of the franciscana (Pontoporia blainvillei) using the traditional knowledge of artisanal fishermen in the villages of Peças Island (VPI) and Superagui Island (VSI) in the World Heritage listed Paranaguá Estuarine Complex, Brazil. Between March and September 2012, 90 fishermen were interviewed (VPI – 40; VSI – 50) using a semi-structured questionnaire. Using Fuzzy logic (MATLAB 7.6) it was verified the species is easily recognized by body size, colour and occurrence area (VPI – 87.5%; VSI – 38.0%). Fishermen most frequently identified adults and young franciscanas in groups of two to five individuals (VPI – 40.0%; VSI – 58.0%). Adults were sighted throughout the year, while the young were restricted to summer and winter. Five common behavioural ethno categories were described: ‘eat’ (VPI – N = 15; VSI – N = 1); ‘float/sink/dive’ (VPI – N = 34; VSI – N = 12); ‘breathe’ (VPI – N = 11; VSI – N = 5); ‘mothers surrounding the shoal, play caught up and the youth captures’ (suggesting care parental related with feeding of infant) (VPI – N = 1; VSI – N = 2); and ‘to play’ (VPI – N = 6; VSI – N = 1). The information from the fishermen highlights the use of the area by franciscana for feeding and reproduction and these data are comparable with the literature. These results extend the knowledge about the species in an area of ecological interest and the traditional knowledge, but also illustrate the benefits of engaging fishermen to promote collaboration in scientific and management processes.

Sea surface temperatures have been taken daily at Keppel Pier, Millport (55° 44‘ 55“ N. lat.; 4° 54’ 20” W. long.), for the past 10 years (1949–58), the data being included in returns to the Meteorological Office. The records are not given in their standard publication and they are, therefore, presented here to supplement those of Cooper (1958) for inshore waters at Plymouth some 400 miles farther to the south. For some years the samples were drawn in a specially constructed container fitted with a Fahrenheit thermometer which was read to the nearest whole degree; more recently the bucket method has been used, and a centigrade thermometer graduated in degrees and read to an estimated tenth of a degree. The two methods were checked against each other before the change was made and the results found to be consistent. All readings were taken at 09.00 h G.M.T., irrespective of the state of the tide. The results are shown in Table 1.

Sections I and II. Amongst the stock of Gammarus chevreuxi which had been kept under Laboratory conditions for at least two years a small number of animals appeared in which the coloured retinal pigment was absent, whilst the white extra-retinal pigment remained. The experiments described in the present paper have shown that these eyes were of two different kinds.

Eyes of the first kind were derived from a stock which originated in a cross between Black-eyed and Red-eyed animals, and were degenerate and irregular in shape. Four animals of this kind appeared in one brood, and such eyes have since been seen only in direct descendants from these. Eyes of this kind were found to behave as simple Mendelian recessives to eyes showing coloured retinal pigment, whether that pigment was red or black, and they are referred to in this paper as “albino” eyes.

Here we present a comparison of saddle and eye patch patterns of killer whales from Norwegian, Icelandic, British, Spanish and Greenlandic waters. We found only a small amount of variation in saddle patch shapes, which may reflect a recent phylogenetic divergence from the most recent common ancestor. Eye patch shapes were more variable than saddle patches in small details. Most individuals had eye patches with parallel orientation, with the exception of a small group of killer whales from the Hebrides, which, as previously reported, had sloping eye patches that sloped downward at the posterior end. This differentiation in pigmentation patterns of the Hebridean killer whales from neighbouring populations could reflect one or more of several evolutionary processes, including a deeper phylogenetic divergence, low gene flow with other local populations and drift.

The mussel Mytilus edulis (Mollusca: Bivalvia) feeds on suspended matter filtered from the sea-water by cilia on the gill surfaces. The bivalve will clear the inhalant water of all particles >2–3 (xm including both sediment and organic matter. Marine sediments act as sinks for a variety of pollutants which may be concentrated up to 1000 fold above water levels. In a series of experiments, the uptake of zinc by M. edulis from filtered sea-water was compared with that from sea-water containing particulate matter acting as model sediments. The materials were two different ion-exchange resins, inorganic granules and hydroxyapatite particles. The accumulation of zinc from the particles was related to the amount of zinc adsorbed by the particles and to their surface properties.

The network of roots and rhizomes of seagrasses plays an important role in coastal ecosystems by anchoring the substrate firmly, controlling the biogeochemistry of the sediments and providing habitat for many infaunal organisms. The purpose of this study was to compare five seagrass communities in southern Thailand in terms of species composition, belowground biomass, redox potential and the abundance of the dominant bivalve Pillucina vietnamica. The communities of Halophila ovalis, Cymodocea rotundata, Thalassia hemprichii, H. ovalis with C. rotundata and C. rotundata with T. hemprichii were studied. Belowground biomass, redox potential, bivalve abundance and bivalve size differed among communities and depths (P < 0.05). The redox potential in vegetated areas was lower than in bare sand, showing that seagrass roots trapped more organic matter than did bare sand. The lowest redox potential was in a monospecific patch of the branching root species, C. rotundata. The abundance of P. vietnamica in vegetated areas was lower than in bare sand (P < 0.05). Pillucina vietnamica was relatively large in size in the monospecific stands of C. rotundata and T. hemprichii, where relatively high root biomass and belowground biomass, respectively, were found. Our results suggest that seagrass promotes anoxic conditions belowground by trapping sediment but could obstruct the burrowing activity of lucinids, as dense populations of lucinids occurred mainly in bare sand. However, seagrass also provided shelter for lucinids, as larger bivalves were found in seagrass areas. The interactions among belowground seagrass parts, the biogeochemistry of sediments and the lucinids are highly complex and merit further study.

Germination of cysts serves as inoculum for the proliferation of some dinoflagellates, and cyst abundance in sediments represents crucial information to understand and possibly predict Harmful Algae Blooms (HABs). Cyst distribution is related to the physical characteristics of the sediments and the hydrodynamics (circulation) of a particular region. In the northern Gulf of California (nGC) several Gymnodinium catenatum HABs have been recorded. However, the presence of resting cysts and the effect of hydrodynamics on their distribution in the nGC have not been investigated. This study evaluated cyst abundance, distribution and their relation to local circulation in surface sediments during two periods that coincided with a non-bloom year condition (July 2016) and after a major HAB registered in the nGC that occurred in January 2017. Also, a numerical ocean model was implemented to characterize the transport and relocation of cysts and sediments in the region. Gymnodinium catenatum cysts were heterogeneously distributed with some areas of high accumulation (as high as 158 cyst g−1, and 27% of total cyst registered). Cysts seemed to be transported in an eastward direction after deposition and accumulated in an extensive area that probably is the seedbed responsible for the initiation of HABs in the region. The nGC is a retention area of cysts (and sediments) that permit the formation of seedbeds that could be important for G. catenatum HAB development. Our results provide key information to understand G. catenatum ecology and specifically, to understand the geographic and temporal appearance of HABs in the nGC.

The ctenostome bryozoan Alcyonidium diaphanum is widespread and abundant in the coastal waters of England and Wales. It was recorded in 77–90% of beam trawl catches in the eastern English Channel and southern North Sea, and in 53–73% of catches in the Bristol Channel and Irish Sea. The maximum catch rates in these two study areas were 1410 and 751 kg h−1 respectively. Alcyonidium diaphanum was most abundant in the greater Thames Estuary. Additional data from the North Sea indicated that A. diaphanum is widely distributed throughout the southern North Sea. Alcyonidium diaphanum was found intertidally in only seven of 99 locations sampled. Several different morphotypes were observed, ranging from cylindrical to lobate forms. The distribution patterns of various morphotypes are discussed.

In some metazoans, the body surface is entirely or partly covered with an array of nipples about 100 nm or less in height. This structure, a nipple array, is sometimes called the moth-eye structure because it serves as an anti-reflection property on the compound eyes of a night moth. The nipple array is supposed to be a multifunctional structure since this structure occurs in various species across different taxa. Here, we hypothesize that the nipple array may prevent the settlement of epibionts that are often a nuisance and potentially cause serious problems for the host. Using a synthetic film that imitates the nipple array, we tested the substrate selection within ascidian larval settlement. The results indicate that the nipple array has anti-fouling properties, since more larvae settled on the flat surface than the nipple array (P < 0.01, paired t-test). The present results demonstrated that the nipple array potentially serves an anti-fouling function on the body surface, which should be important especially for sessile organisms.

The spiny butterfly ray Gymnura altavela (Linnaeus 1758) is classified as Endangered by the International Union for Nature Conservation (IUCN) and considered Critically Endangered in the Mediterranean Sea and South-west Atlantic. Despite its status, few studies on the population biology and genetics for the species are available, undermining conservation efforts. In the present study, we evaluated the taxonomic status of Gymnura altavela along both sides of the Atlantic using COI sequences. Our genetic data support the existence of two genetically differentiated G. altavela lineages (West and East Atlantic) and further studies are required to evaluate the hypothesis that these lineages could, in fact, be cryptic species within this endangered batoid's genus.