Ambergris is a rare substance produced in the intestines of sperm whales. It appears to result from an irritation caused by the beaks of the cephalopods on which they feed. The link between ambergris and whales, if not the mechanism by which ambergris is produced, has been addressed throughout history but, due to contradictory reports and fanciful explanations regarding its origin, only recently has it been widely accepted. Since ancient times ambergris has been used for medicinal purposes and in perfumes, but its supposed exotic properties are an important reason for the European demand for this substance. Accounts about ambergris from places where Europeans sailed since the 15th century are numerous. In the 16th and 17th centuries there were no laws dictating who owned the ambergris found on beaches and many pieces were sold or traded, legally or illegally, from overseas to Europe. However, this product was always obtained in relatively small quantities. More recently, with the advent of industrial whaling dedicated to sperm whaling conducted by several nations in various parts of the world during the 19th and 20th centuries, ambergris acquired an importance of its own and was sold at very high prices. In the Azores, ambergris from hunted sperm whales was documented; the same applies for Madeira and the Portuguese mainland. Being a product typically reported in whaling data and related to the economic exploitation of the sea, it is through the historical sources that its importance is clearly demonstrated.

Phelloderma oxychaetoides sp. nov. is a remarkable new species from the deep Weddell Sea, bearing abundant oxychaetes (onychaete-like microxeas), morphologically distinct from the onychaetes of Tedania spp. collected in the same area. We give a redescription of the holotype of P. radiatum Ridley & Dendy, 1886, the type species of Phelloderma. We recognize three and a possible fourth species in Phelloderma: P. flava (Lévi, 1993); P. oxychaetoides sp. nov.; P. polypoides Whitelegge, 1906; and P. radiatum Ridley & Dendy, 1886. An identification key for the species of Phelloderma is proposed. A discussion on the affinities of Phelloderma to both Mycalina and Myxillina is offered, and the current preference for the latter is further supported by the marked similarity between the oxychaetes of Phelloderma oxychaetoides sp. nov. and those of Chaetodoryx spp. (Coelosphaeridae, Myxillina).

Sponges (phylum Porifera) are important components of the benthic marine fauna known for their interactions with vertebrates and a large sort of invertebrates seeking for food, shelter or substrate for attachment. Studies on this subject, however, were restricted only to the macrofauna inhabiting sponges of the class Demospongiae. In the present work, we describe the macrofauna associated with a calcareous sponge in Brazil, Paraleucilla magna. Individuals of this allegedly non-native species were monthly collected during one year in Rio de Janeiro (Brazil). Fifty taxa representing 10 animal phyla were found associated with P. magna. The most frequent and abundant taxa were Crustacea, Mollusca, Polychaeta and Bryozoa, while echinoderms, cnidarians, ascidians, nemerteans, platyhelminthes and sponges were less frequent or even rare and less abundant. Juveniles of several taxa and pregnant females of Crustacea were found associated with P. magna, but these associations were not exclusive. The macrofauna associated with P. magna did not present a clear seasonality, although it was possible to observe a change in the community composition alongside the year. The volume of the sponges was significantly related to the diversity index (H′) and number of taxa, but not with evenness (J′) and number of individuals. Our results show that P. magna is used as a substrate for attachment and/or shelter by its associates and that most of these associations are just opportunistic. The data presented here reiterate a previous proposal that sponges are important biodiversity reservoirs and that they should be seriously considered in conservation programmes.

The swimming crab Achelous spinimanus is an important fishery component of several countries in the Western Atlantic; therefore, knowledge of the different phases of its life cycle is essential for good management of this resource. The juvenile development of A. spinimanus was investigated in the laboratory, from megalopae captured in neuston samples at Ubatuba, São Paulo, Brazil (23°26′S 46°09′W), during the summer months of 2005–2007. Rearing was performed in a constant temperature (25 ± 1°C), filtered seawater from the collection location (35 psu) and natural photoperiod. We obtained nine stages of the juvenile phase. All the morphological characters that allow the recognition of the first juvenile stage were drawn and described, as well as the main alterations that occur in the following stages. The sexual differentiation based on the number of pleopods becomes apparent from the third stage on. Some important characters in the identification of the species at the juvenile phase are the number of segments on the exopod of antennule, on the antennal flagellum and on the palp of mandible, beyond the absence of pleopods (even rudimentary) in the first stage.

Soft bottom intertidals of the Atlantic SW are dominated by the semi-terrestrial crab Neohelice granulata and the grapsid crab Cyrtograpsus angulatus. They are similar in size but C. angulatus is mainly a subtidal species, while N. granulata inhabits the intertidal zones, thus the two species overlap only during high tides in this area. Since these distribution differences between crab species across the Mar Chiquita Coastal lagoon may affect digenean infection success, the objective of this work is to describe the spatial differences in parasite infection levels and their selectivity on the host. To determine possible spatial differences in parasitism levels between sites and crab species across the lagoon, three areas dominated by N. granulata were selected and adult crabs of N. granulata and C. angulatus were collected. Both crab species harboured metacercariae of the digeneans Microphallus szidati and Maritrema bonaerensis (Microphallidae), and cystacanths of the acanthocephalan Profilicollis chasmagnathi (Profilicollidae). Digenean species showed preferences between the two crabs. Maritrema bonaerensis mean intensity was higher in N. granulata than in C. angulatus, while the opposite trend was found for M. szidati and could indicate some level of specificity. These results, nevertheless, depended on the study site. For P. chasmagnathi the highest values of mean intensity depended more on the site than on the crab species. The values found here, compared with previous works from both crab species, suggest that besides the spatial heterogeneity, interspecific competition between parasites could explain the differences observed.

This paper provides for the first time data on age and growth of Remora osteochir, also describing its sagittal otolith together with other biological and ecological aspects. Overall, 236 individuals of marlin sucker were collected in the southern-central Mediterranean Sea, from 2008 to 2009. All samples were hosted by the Mediterranean spearfish, Tetrapturus belone, caught by surface longline and harpoon. Analysis of gonads identified a reproductive peak during June and July. The estimated growth parameters according to the von Bertalanffy equation were: L∞ = 27.37 cm TL, k = 0.248 year−1, t0 = −1.36 year. The length-weight relationship, computed by using eviscerate weight, highlighted an isometric growth for both sexes, as supported by the other results: similar sizes, growth curves and disc length-total length relationship.

The life history of the Japanese sternaspid polychaete Sternaspis costata von Marenzeller, 1879 was investigated in the inner part of Ariake Bay from May 2010 to May 2011, with additional sampling in July and September 2011. All the worms were measured by the width of the ventral shield (WS) as an indicator of body size, and their coelomic contents were also examined. Ovigerous females occurred throughout the year, except during October and March, with the highest ovigerous rate (number of ovigerous females/number of adults with a WS larger than that of the smallest ovigerous female, i.e. 1.8 mm) noted in September (43.8% in 2010, 34.7% in 2011). The ovigerous rate was less than 10% in the other months, except in April 2011 (30%). Although the coelomic oocytes ranged from 90 to 160 μm in diameter, the diameters of most of the oocytes were 140–160 μm in September. The number of adults drastically decreased from September to October, suggesting that most of the adults died after spawning in the major reproductive period, although a small fraction of adults seemed to reproduce earlier or later. A cohort of recruits with an approximately 1.2 mm WS was identified in March and April. Most of the recruits grew to adult size in July–September, when many ovigerous females occurred. These results indicated that this species is fundamentally semelparous, with longevity around 1 year, and they mostly reproduce in September, with a few adults reproducing almost throughout the year.

The Lusitanian toadfish, Halobatrachus didactylus, like other batrachoidids, is a benthic fish species with nesting behaviour during the breeding season. During this prolonged period it engages in mating activities and remains in the nest providing parental care. It is not known whether males feed while providing parental care but it is likely that their limited mobility may restrict their diet and influence their fitness. As a consequence, egg cannibalism could occur as a life-history strategy. The aim of the present study is to ascertain the feeding behaviour of nesting males, in comparison to mature non-nesting males, and to identify potential life-history traits related to egg cannibalism. Nest-holders were sampled from artificial nests placed in an intertidal area of the Tagus estuary, only exposed during spring low tides. The diet of nest-holders was compared with that of non-nesting mature males from the same area, captured by otter trawl. The present study demonstrates that despite their constrained mobility nest-holders feed during the breeding season, although in a more opportunistic fashion than non-nesting males. Nest-holders showed a generalist feeding behaviour, with a more heterogeneous diet. Egg cannibalism was not related to male condition, paternity or brood size but showed a higher incidence early in the season when water temperatures were lower. The results suggest a possible seasonal trade-off strategy between care and energy recovery, triggered by environmental factors, where under unfavourable conditions to sustain viable eggs the male may recover energy by eating eggs, thus benefiting future reproductive success, later in the season.

Clarification of the life-history traits of a symbiont and its host is necessary to evaluate the relationship between them. Stylochoplana pusilla, a polyclad, inhabits the mantle cavity of the eulittoral snail Monodonta labio. This study elucidated the life-history traits of S. pusilla relative to those of M. labio in a tide pool, which retained seawater, and a boulder shore, which was dry at low tide, in Mutsu Bay, northern Japan, from 2010 to 2012. In these habitats, S. pusilla was semelparous with a 1-year life cycle; it reproduced in midsummer and inhabited the shell of M. labio except for the early juvenile stages, which were planktonic. More juvenile S. pusilla newly settled on hosts in the tide pool than on the boulder shore, however, their survival rate was higher on the boulder shore compared with the tide pool. The growth rate of juvenile S. pusilla was higher in the tide pool than on the boulder shore. The higher growth rate of S. pusilla at the tide pool suggested that they were more actively feeding. Stable isotope analysis showed that S. pusilla acquired food resources outside the host snail both in the tide pool and on the boulder shore. Thus, it was likely that S. pusilla engaged in feeding outside the host snails but resulted in lower survival rates at the tide pool. These results suggest that S. pusilla is semi-free living and uses M. labio as a refuge in the eulittoral zone for protection against desiccation.

Two new demosponges, Megaciella pituitosa and Cladocroce toxifera, are described from the Aleutian Islands, fostering our contention that the region is a hotspot of poriferan biodiversity. Seven of the thirteen species of Megaciella now known worldwide occur in the Sea of Okhotsk or around the Aleutian Islands. Similarly, five of the sixteen species of Cladocroce known worldwide occur in Alaska. Megaciella pituitosa sp. nov. possesses two categories of choanosomal styles and spicules of different sizes that differentiate it from all known congeners. Cladocroce toxifera sp. nov. differs from all known congeners by possessing toxa and an ectosomal tangential arrangement of oxeas.

Dercitus (Stoeba) pseudodiscorhabda sp. nov. is described from the tropical western Atlantic. It is the only Dercitus (Stoeba) with four-rayed calthrops and discorhabds-like sanidasters. This is the 16th species of the genus to be recognized worldwide, the sixth from the Atlantic. The new species is compared with all its congeners worldwide.

Didiscus gladius sp. nov. is described from Bahia State (Brazil). The sponge is thinly encrusting to lump-shaped and has a glassy, translucent appearance, through which the spiculation is clearly visible. The megascleres are styles and two categories of oxeas. The microscleres are discorhabds. Colour is beige or brown in ethanol. Didiscus verdensis is the nearest relative in the Atlantic which differs from the new species in a series of traits (e.g. absence of true styles and presence of strongyles). A key to species of Didiscus is given.

Members of the tubicolous polychaete family Serpulidae constitute one of the most important groups of marine fouling biota. This paper describes a new species of the serpulid genus Hydroides from dock fouling at Mazatlán (southern Gulf of California), providing information about live colouration and reproductive features. Hydroides dolabrus sp. nov. belongs to a subgroup of species in which verticil spines are equal in size and shape, lack both external and lateral spinules, but have various modifications to their tips. However, Hydroides dolabrus sp. nov. is distinct in having tips of verticil spines pickaxe-shaped, with asymmetrical triangular radially orientated projections: the internal projections are short and point inward the verticil centre, while longer external projections point outward the verticil centre. Like all species of the genus, H. dolabrus sp. nov. is a gonochoristic broadcast spawner lacking sexual dimorphism. A phylogenetic analysis of Hydroides based on COI, 18S and cyt b sequence data reveals that H. dolabrus sp. nov. is genetically distinct from other species of Hydroides for which sequence data are available. The new species is the 11th in the genus described from Mexican waters.

Coral reef associated marine invertebrates, such as the blue sea star Linckia laevigata, have a life history with two phases: sedentary adults and planktonic larvae. On the one hand it is hypothesised that the long pelagic larval duration facilitates large distance dispersal. On the other hand, complex oceanographic and geographic characteristics of the Visayan seascape could cause isolation of populations. The study aims to investigate the genetic diversity, genetic population structure and gene flow in L. laevigata to reveal connectivity among populations in the Visayas. The analysis is based on partial sequences (626 bp in length) of the mitochondrial cytochrome oxidase I gene (COI) from 124 individuals collected from five localities in the Visayas. A comparative analysis of these populations with populations from the Indo-Malay Archipelago (IMA) published previously is also presented. Genetic diversity was high (h = 0.98, π = 1.6%) and comparable with preceding studies. Analyses of molecular variance (AMOVA) revealed a lack of spatial population differentiation among sample sites in the Visayas (ΦST-value = 0.009; P > 0.05). The lack of genetic population structure indicates high gene flow among populations of L. laevigata in the Visayas. Comparative analysis with data from the previous study indicates high connectivity of the Visayas with the central part of the IMA.

Diatoms are a primary producer and play an important role in the functioning of microbial food webs. Temporal variations in community patterns of planktonic diatom assemblages were studied during a 1-year cycle (June 2007–May 2008) in Jiaozhou Bay, northern China. Samples were collected biweekly at a depth of 1 m from five sampling stations. A total of 75 diatom species representing 40 genera, 28 family, 19 orders and three classes were recorded. Of these species, 11 distributed in all four seasons, while 27, 35, 56 and 28 forms occurred only in spring, summer, autumn and winter season, respectively. The species number and total abundance peaked in autumn, with minimum values in May. All three species biodiversity measures (Shannon diversity, Pielou's evenness and Marglef's richness) peaked in spring and autumn. There was a significant difference in diatom community patterns among seasons, except the pair of spring and winter. The environmental variables, especially temperature and the nutrients, could significantly drive the seasonal variation in diatom community patterns. Of 11 dominant species, four (Paralia sulcata, Skeletonema costatum, Guinardia delicatula and Nitzschia lorenziana) were significantly related with temperature, pH and/or nutrients. These findings suggest that the seasonal shift in community pattern of planktonic diatoms was driven by both temperature and nutrients in this eutrophic basin ecosystem.

The structural complexity of macrophytes that provide various microhabitats is related to local infaunal abundance and diversity. Seagrass is considered an ecosystem engineer that alters the benthic environment and enables certain distinct meiofauna to thrive in sediments. The effects of seagrass species in a mixed-species seagrass bed at Haikou, Taiwan were examined. Analysing quantitative samples obtained from patches of Thalassia hemprichii, Halodule uninervis, Halophila ovalis and adjacent unvegetated sediments inspected the community structures of meiofauna and marine nematodes. The abundance and diversity of crustaceans and nematodes were substantially higher in habitats in which seagrass grew than in those comprising unvegetated sediments. Both the compositions of higher meiofaunal taxa and nematode species were distinct between seagrass habitats and unvegetated areas. Several nematode species existed exclusively in patches of individual seagrass species, whereas no nematode specifically occurred in unvegetated areas. Regarding the trophic types of nematodes, non-selective deposit feeders were prevalent in the present study, whereas selective deposit feeders and epistrate feeders were relatively dominant in seagrass habitats. Sediments underneath various patches of seagrass species harbour dissimilar nematode communities, even with similar sediment parameters and at a small-scale distance.

The trophic structure of Ascension Island's sub-tidal reef assemblages is poorly understood. Unlike other tropical reef systems, sub-tidal habitats have very low abundance of both coral and macrophyte species. Visually dominant is a diverse assemblage of fish species, with particularly high densities of Melichthys niger, a voracious omnivore. In contrast, the nocturnal species assemblage is notably different, visually dominated by benthic invertebrates. To quantify the difference between day and night visible assemblages, we conducted day/night pairs of transect surveys of fish and invertebrates across three depths, and spanning 9 months, assigning all species to one of 10 functional groups. Multivariate analysis of surveys revealed significant turnover in species between day and night surveys and between survey periods, with concomitant changes in species rank-abundance distributions. Juveniles of a number of fish species were determinate in observed differences. Conversely, diversity of functional groups between day/night surveys and between seasons were not different, however there was significant species turnover within functional groups between day and night assemblages. The lack of proportional change in functional groups but a turn-over of species between day and night assemblages suggest that there may be a degree of functional redundancy in Ascension Island's marine trophic profile. Further investigation into the spatio-temporal variation in trophic profile and functional diversity around the island will benefit conservation and fisheries management in this isolated and poorly understood marine system.

From September 2000 to September 2001 the concentration of chlorophyll a, and the abundance and composition of the phytoplanktonic community was studied in a neritic station of the Mallorca Channel (Western Mediterranean). Sampling was performed approximately every 12 days. Chlorophyll a concentration and phytoplankton abundance reached maxima of 1.79 μg L−l and 352 cells mL−1, respectively. It was a relatively productive period, as a result of the high convective mixing in winter and the prevalence of northern waters during most of the cycle. Phytoplankton proliferations (chlorophyll a concentration >1 mg L−1) were detected in January, February, March and June. Those blooms mainly happened under the influence of northern waters, with the exception of the February proliferation, when mixing conditions were found. During bloom conditions it highlights the presence of coccolithophores as proliferation precursors. During no-bloom situations the phytoplankton community was mainly constituted by nanoplanktonic flagellated forms. The Winter Mixing period was dominated by different groups of nanoflagellates, including coccolithophores, undetermined flagellates and dinoflagellates. However, in the most oligotrophic conditions (from April until November) dinoflagellates were clearly dominant, except in the DCM in summer where diatoms prevailed.

Peracarid crustaceans are an important component of the vagile fauna associated with coralline algal beds, which often characterize the infralittoral fringe of tropical rocky shores. Among other variables affecting faunal assemblages, sedimentation, food supply and oxygen concentration within mats or turfs of coralline algae may greatly depend on the exposure to waves. In this study, peracarid assemblages were compared at replicated rocky shores within different levels of wave exposure, along a coastline in south-eastern Brazil. Overall amphipod diversity (11 species) was much higher than tanaidacean diversity (two species). Correlation analyses did not support any biological interactions between amphipods and tanaidaceans. Habitat complexity, while apparently limiting amphipod populations, did not affect tanaidaceans at a local scale. Amphipod abundance, not assemblage structure, was positively affected by wave exposure, probably improving oxygen concentration levels and renewal of food resources. Rather than abundance, which remains fairly stable, exposure to waves determined species identity in tanaidaceans, with Zeuxo coralensis found at exposed shores and Leptochelia aff. dubia found at sheltered shores, except for two L. aff. dubia individuals found at one of the exposed sites. Differences in the supply of sediment and the ability of these species in manipulating grains for tube building may explain such a striking pattern.