one of 353 port jackson sharks, heterodontus portusjacksoni, caught off the southern coast of western australia, was a hermaphrodite. the female reproductive tract consisted of a large (functional) right ovary with three large yolked ova, a small non-functional left ovary and two well-developed uteri and oviducal glands. the male tract comprised two conspicuous but undeveloped testes, two vas deferens and two calcified claspers with grooves. this individual represents the first published example of hermaphroditism in the order heterodontiformes and is a rare example of an elasmobranch with a complete suite of both male and female reproductive structures.

Pectenogammarus planicrurus Reid (Crustacea: Amphipoda) is an inhabitant of unstable gravel beaches. The reproductive output of females of this species was studied at Aberystwyth, on the west coast of Wales. There was marked seasonal variation in the size of eggs: the mean volume of eggs at an early stage of embryonic development ranged from 0·023 mm3 in summer to 0·030 mm3 in winter. Egg size was negatively related to brood size, but seasonal variation in brood size was greater than could be accounted for by egg size alone. Mean brood size ranged from 1·4 eggs in winter to 5·9 eggs in summer. Brood size was also strongly related to female body size, ranging up to 14 eggs in a large female. These findings are discussed in relation to adaptation to interstitial living in coarse intertidal gravels. A model of seasonal variation in reproductive output is suggested in which the importance of point reproductive output is related to the probability of females surviving to produce subsequent broods.

The relatively shallow coldwater coral reefs growing off the eastern coast of Mingulay, north-west Scotland, are excavated by five sponge species, three of which, Alectona millari, Pione vastifica and Cliona lobata, were known previously from Scottish waters. The other two species are new to Scotland and Great Britain. One species is here described as new to science: Cliona caledoniae sp. nov. The species shows a superficial resemblance in colour (orange) and spiculation (possession of tylostyles and knobby microscleres) to Cliothosa hancocki described disjunctly from the Pacific Ocean and the Mediterranean Sea, but it differs clearly in lacking the characteristic Cliothosa amphiasters with branching rays. The Scottish species only possesses peculiar thick-rayed streptasters, which at first glance appear rather similar to the second microsclere type reported for Cliothosa hancocki, knobby-rayed amphiasters. However, the majority of the microscleres in the Mingulay species appear to be genuine spirasters (not amphiasters), and exhaustive search for true amphiasters, branching or otherwise, was in vain. The new species is extensively illustrated. Furthermore, we also report the first occurrence in British waters of Spiroxya levispira, originally described from Azorean deep waters, and subsequently reported from Madeira and several Mediterranean localities. It was found to occur not uncommonly in the Mingulay reefs, and additionally also in reefs of the Rockall Bank, west of Ireland. The spicular characters generally match those of the southern locations. The newly recorded species is described and amply illustrated.

Population dynamics and production of the spionid polychaete Marenzelleria viridis were studied at Great Sippewissett salt marsh (Massachusetts, USA) for two years. Marenzelleria viridis was the main contributor in biomass and production to the macroinfaunal assemblages of the sandy organic sediments of the marsh. Marenzelleria viridis spawned during the cold part of the year and the appearance of settled larvae on sediments was observed from January to May. The density of M. viridis rose sharply from winter to late spring followed by a striking drop through summer. The estimated mean annual production of M. viridis was 60.0 g dry weight m2 during the first year and 26.3 g dry weight m2 during the second year. The population of M. viridis is affected by different processes during the year. The number of initial recruits seems to be largely governed by meteorological conditions. The numbers of recruits are then affected by competition for resources, and later, as predators become active, predation pressure determines the abundance of the population of M. viridis.

The population structure of the European flying squid Todarodes sagittatus was studied using data of about 5000 squid caught in waters off the western Sahara between 1969 and 1997. The bulk of the population consisted of winter-spawned squid, which occurred as juveniles of 80–120 mm mantle length (ML) over the slope in spring, and as immature squid of 160–180 mm ML both on the shelf and slope in summer. In autumn, the squid attained 220–280 mm ML, matured, and shifted to the slope, where the spawning was supposed to occur in winter. Age and growth of T. sagittatus was studied using statolith ageing techniques. Assuming daily production of putative growth increments within statoliths, as well as sizes and proportions of immature and maturing females, the lifespan of the west Saharan populations of T. sagittatus lasts ∼1 y. Todarodes sagittatus is a fast growing squid at juvenile and immature ontogenetic phases. Early maturation (at ages 220–230 d in males and 250–260 d in females, respectively) and subsequent decrease of somatic growth rates caused rather small modal sizes of mature squid (250–300 mm ML) compared with those of their northern counterparts (350–420 mm ML). Both hatching dates and seasonality in occurrence of mature females shows that in waters off the western Sahara T. sagittatus spawns throughout the year with a well-pronounced winter peak.

The abundance pattern and species diversity of phytoplankton in the surface waters of the Golden Horn Estuary were investigated between August 2011 and July 2012 in relation to environmental factors. Seventy-eight phytoplankton taxa (38 diatoms, 30 dinoflagellates and 10 phytoflagellates) belonging to eight taxonomic classes were identified in bottle and net samples. Phytoplankton abundance increased in spring and summer (from March to August) and reached its highest (10,429 × 103 cells L−1) during the bloom of Heterosigma akashiwo (Raphidophyceae) in the middle and upper estuary in late May. In general, phytoplankton abundance was higher in the middle estuary indicating more suitable conditions for phytoplankton growth, while species richness and diversity was higher in the lower estuary. The most abundant species were Skeletonema marinoi and Thalassiosira sp. among diatoms; Scrippsiella trochoidea among dinoflagellates; Plagioselmis prolonga and Heterosigma akashiwo among phytoflagellates. Diatoms were more abundant in the lower and middle estuary, while dinoflagellates and phytoflagellates in the upper estuary. The main factors causing the spatio-temporal variation of phytoplankton in the study area were temperature, salinity, water transparency and nutrients. Water transparency in the upper estuary is mostly influenced by organic and inorganic matter carried by two streams. As a result, this area should be considered a potential risk area for future algal blooms.

Life history accounts for the chance of survival and reproductive success of a species, considering, for example, when, how often and how much a species reproduces. Consequently, it is directly related to the success or failure of bioinvasions. Here, we investigated some aspects of the life history of the cryptogenic calcareous sponge Sycettusa hastifera. A population from Arraial do Cabo, Brazil (south-western Atlantic) was investigated from September 2008 to December 2009 by monthly collections and histological analyses. We observed that S. hastifera reproduced continuously throughout the year without seasonality and presented high fecundity. The fecundity was not different depending on the sponge body part (top or base), but it was related to the wet weight of the sponge (although a minimum size was not required for reproduction). Reproduction could not be predicted by the seawater temperature. The reproductive characteristics of S. hastifera were similar to those of other previously studied calcareous sponges. Sycettusa hastifera shows traits of an invasive species, such as high fecundity, short life cycle, early sexual maturity and the ability to use pioneer habitats. Consequently, it possesses several characteristics that would allow it to invade new areas.

A study was initiated to identify trematode patterns in Cyathura from two key sites in the Mondego Estuary: a Zostera-bed and a sand flat. The two subpopulations of Cyathura differ, as the annual recruitment success is much higher and more regular on the sandflat than on the Zostera-bed.

Counting and sizing of trematode cysts inside the body of preserved Cyathura specimens enabled a description of trematode patterns in space and time. Further identification of trematodes was based on DNA studies of unpreserved cysts as well as on identification of parasites in co-occurring mud snails. Two trematode species dominated in Cyathura: Maritrema subdolum (cysts around 190 μm) and a hitherto unknown Levinseniella species (cysts around 340 μm), the latter being the most frequent one. Generally, the prevalence of both species peaked during winter months, when migratory water birds occur in the estuary. Cyathura from the Zostera bed harboured more infections per specimen than those from the sand flat. A much higher density of mud snails ≥52 mm (which can be host to microphallids) and a low abundance of Cyathura are thought to be the main reasons for this pattern. Field data did indicate a host size-dependent maximum number of cysts in Cyathura that could be a result of enhanced mortality at high cyst intensities. Furthermore, parasites were underrepresented among ovigerous Cyathura specimens, suggesting a negative impact on gametogenesis. As a consequence, microphallid trematodes may be a critical factor controlling recruitment strength in Cyathura, especially at the Zostera-site.

Two new species of South African Syllidae of the genus Syllis Lamarck, 1818 are described. Syllis unzima sp. nov. is characterized by having unidentate compound chaetae with long spines on margin, a characteristic colour pattern and its reproduction by vivipary. Vivipary is not common among the polychaetes, but most representatives occur in the family Syllidae Grube, 1850 (in five other Syllis species, two species of Dentatisyllis Perkins, 1981 and two species of Parexogone Mesnil & Caullery, 1818). Syllis unzima sp. nov. differs from the other viviparous species in having large broods (>44 juveniles) which develop synchronously. Development of the juveniles is similar to that of free-spawning Syllis species, but the appearance of the first pair of eyespots and the differentiation of the pharynx and proventricle occur later in S. unzima. Syllis amicarmillaris sp. nov., is characterized by having an elongated body with relatively short, fusiform dorsal cirri and the presence of one or two pseudosimple chaeta on midbody parapodia by loss of blade and enlargement of shaft. Syllis unzima sp. nov. was found in high densities on cultured Holothuria scabra Jaeger, 1833 with single specimens found on a cultured Crassostrea gigas Thunberg, 1793 and on coralline algae, respectively, while S. amicarmillaris was found mainly in sediment outside an abalone farm and less frequently on cultured Haliotis midae Linnaeus, 1758. We discuss the possible benefits of the association with H. scabra to S. unzima sp. nov.

The aim of this study is to characterize the different macrozoobenthos communities in Mar del Plata waters (south-western Atlantic) on the basis of their abundance and habitat, and to determine how sediment characteristics, like the grain-size composition, affect macrobenthic community structure. Multivariate techniques indicated that benthic communities and sediments in the surveyed area were included into the following five well-defined groups: (1) a medium sand assemblage dominated by the bivalve Crassinella marplatensis and Diplodonta patagonica, the echinoderm Encope emarginata, the tanaidacean Bacescapseudes sp. and the polychaete Armandia loboi; (2) a medium to very fine sand assemblage dominated by ostracods, the tanaidacean Bacescapseudes sp., amphipods and polychaetes of the family Nephtyidae; (3) a fine to very fine sand assemblage dominated by the tanaidacean Bacescapseudes sp.; (4) a silt and fine sand assemblage dominated by polychaetes particularly Scolelepis sp. and individuals of the family Nephtyidae; and (5) a fine sand assemblage dominated by amphipods and the tanaidacean Bacescapseudes sp. These results revealed the patchy distribution of macrobenthic assemblages as a result of sediment characteristics and serve as baseline information for this area strongly subjected to trawling perturbations.

Swimming propagules (embryos and larvae) are a critical component of the life histories of benthic marine animals. Larvae that feed (planktotrophic) have been assumed to swim faster, disperse farther and have more complex behavioural patterns than non-feeding (lecithotrophic) larvae. However, a number of recent studies challenge these early assumptions, suggesting a need to revisit them more formally. The current review presents a quantitative analysis of swimming speed and body size in planktotrophic and lecithotrophic propagules across five major marine phyla (Porifera, Cnidaria, Annelida, Mollusca and Echinodermata). Results of the comparative study showed that swimming speed differences among ciliated propagules can be driven by taxonomy, adult mobility (motile vs sessile) and/or larval nutritional mode. On a phylogenetic level, distinct patterns emerge across phyla and life stages, whereby planktotrophic propagules swim faster in some of them, and lecithotrophic propagules swim faster in others. Interestingly, adults with sessile and sedentary lifestyles produce propagules that swam faster than the propagules produced by motile adults. Understanding similarities and differences among marine propagules associated with different reproductive strategies and adult lifestyles are significant from ecological, evolutionary and applied perspectives. Patterns of swimming can directly impact the dispersal/recruitment potential with incidence on the design of larval rearing methods and marine protected areas.

Over the period 1—4 April 1999 a large number of dead asteroids were washed ashore at the northern end of the Isle of Man. The area is commonly used for public recreation and the stranding prompted numerous alarmed telephone calls to various bodies. Initially, disease or pollution were suspected, but a more detailed examination of the circumstances indicated that the mass stranding was probably a result of tides and weather conditions. The stranding occurred on the east coast of the Isle of Man from about 100 m to the south of the Point of Ayre, which is the northernmost point of the Isle of Man, and extended southwards for ≈600 m. This is a highly exposed shore with a strong tidal flow, subtidally it is shallow, with coarse gravel and exposed bedrock, and extensive mussel (Mytilus edulis) beds, which may be expected to attract large numbers of predatory starfish.

The hydroid of the medusa Modeeria rotunda (formerly Tiaranna rotunda) has been found to be the thecate species Stegopoma fastigiatum. The medusa has been obtained from the hydroid and reared to maturity. The stages of development of the medusa are described and figured, and its occurrence and habits are discussed. The affinities of the medusa are considered: it is shown to belong, together with the the genus Chromatonema, to the family Laodiceidae.

The post-larval blennies taken off Plymouth during recent years have been assigned to three species, namely, Blennius ocellaris L., Bl. pholis L., and Bl. gattorugine L. The process of identification, however, has emphasised the need for the revision of the available descriptions and illustrations of the various stages in development, and I have, therefore, thought it desirable to report on the Plymouth forms and give drawings of them.

Blennius Ocellaris (12 rays to the pectorals).

Ehrenbaum (2, p. 83) has copied two figures of the young of this species which were originally produced by Holt (5, p. 45), and it is somewhat unfortunate that both need to be commented upon. The first is satisfactory as a representation of the appearance of a larva some time after hatching, but the length is wrongly given as 6.3 mm. Garstang (4, p. 74) explained that this was an error in transcription, and, after a re-examination of Holt's specimens, he found that the total length was 4.6 mm. (varying between 4.55 and 4.65). The second figure, depicting a young fish of 18 mm., which Holt tentatively assigned to Bl. ocellaris, was taken exception to by Garstang and the identification questioned, and it must be admitted that it does not portray satisfactorily the characters of the species.

The full account of the rearing of the young from the egg by Garstang (4) was unfortunately not illustrated; but as several of his original specimens are in the Plymouth collection, I have been able to identify quite readily the more recently captured examples and have made a series of drawings which are given below (Figs. 1 to 4).

An important part of recent investigations on herrings at Plymouth has been the collection of statistical data on the number of vertebræ, and when this report was written a total of 6869 fishes had already been examined with regard to this character. In the case of each of 105 fishes, however, the true number of vertebræ could not be stated with confidence, owing to marked irregularities in one or more vertebræ. These abnormal specimens are of more than passing interest. The abnormalities themselves are such that it would be well worth while to make a careful morphological study of “ fresh ” specimens to determine the extent to which nerves and muscles are affected. The determination of the distribution of abnormalities along the vertebral column suggests a possible explanation of the way in which they may have arisen. Moreover, there remains the question as to how the abnormal vertebræ should be counted when endeavouring to ascertain the true total number of vertebræ for statistical or genetic purposes. In the paragraphs which follow, the 105 cases of abnormality are described and their significance both in numbers and position discussed, but it should be remembered that all observations and measurements were made on dried skeletons, which had been prepared by boiling and cleaning.

In summer 2001, members of the public in south-west Scotland were interviewed to determine their knowledge of the diversity and occurrence of cetaceans in the region. Interviews were conducted in both rural island and coastal communities and a major city.

The majority of interviewees (46%) underestimated the number of cetacean species occurring in western Scottish waters (i.e. <10 species). Only 4·4% gave the correct answer (24). Location of the participant affected the level of knowledge. Photographs were presented of the four most commonly occurring cetacean species: only 30·2% correctly identified one or more of the species. The species most frequently identified correctly was the bottlenose dolphin (19% of interviewees) followed by the harbour porpoise (17·5%), minke whale (10·7%) and, lastly, the common dolphin (7·1%).

Interviewees were also asked whether certain cetacean species occurred in local waters or not. The level of awareness was generally low. The most common positive answers involved the bottlenose dolphin, harbour porpoise, and minke whale. Only one in five were aware of killer whales and 13·1% believed that grey whales occurred in Scottish waters. Knowledge of species occurrence showed statistically significant relationships with age, gender, level of environmental interest and location, but not occupation (teachers, tourism professionals and marine stakeholders did not show greater levels of cetacean knowledge). The study identified target groups and locations where knowledge of cetaceans is low and environmental education efforts should be concentrated.

The pteropod Clione limacina (Phipps), now regarded as one of the tectibranchs, occurs at times in the neighbourhood of Plymouth. In 1930, however, it was extraordinarily abundant, especially in the summer, and was breeding freely. Although not specially recorded it has been seen singly or in small numbers in almost any month of the year, and for some years the eggs and larvæ (not recognised at the time as belonging to Clione) have been seen in summer. So far it is known from the British coasts in the North Sea and the west and extreme south-west of England. Its distribution, as known up to 1908, is given fully for the area of International Fisheries Investigations by Paulsen (1910). There it is shown that it is an Arctic-boreal species, spreading southwards nearly to the Bay of Biscay, which is about its southerly limit. It is known to occur in the northern and mid North Sea, but not in the southern North Sea, and at that time was only recorded from the Channel in the extreme west. It is also common in the Atlantic. Paulsen was led to infer that Clione limacina did not enter the North Sea from the Channel, but its prevalence sometimes at Plymouth shows that it can come a long way up the Channel and, as few samples are taken to the east and in the southern North Sea, this view should be carefully reconsidered.

Biological traits analysis (BTA) is considered to be a powerful technique for describing the ecological functioning of marine benthic assemblages. This study is the first to apply BTA to assess differences in the traits of benthic faunal assemblages between areas exposed to heavy and light trawling in a major upwelling ecosystem along the west coast of southern Africa. The data were collected from two sampling locations in Namibia and six sampling locations in South Africa. The intensity of trawling varied from area to area. Significant differences in biological traits (BT) were detected between heavily and lightly trawled areas. Weighted infaunal traits showed significant differences between heavily and lightly trawled areas for 17% of the traits investigated, while 24% of epifaunal traits investigated were significantly different between areas of different trawling intensities. This suggests that the measured BTs of the epifauna might be more sensitive to trawling disturbances than BTs of the infauna. The infaunal traits differed significantly between areas with larger or smaller proportions of sand and mud. Nevertheless, more of the significant differences in infaunal BTs were related to variations in trawling intensity than to variations in sediment composition. Significant modifications of BTs are likely to lead to modified functioning of the community and provide more general potential indicators for management than those based on species. The study confirms the need for more basic biological and life history data on macro-benthic invertebrates but nevertheless shows that BTA detected specific features that correlate with trawling intensity and that these features may be important for epifaunal assemblage functioning.

This paper reports the results of experiments designed to investigate the relationship between thermal stability of DNA and the physical and chemical conditions experienced by various species of invertebrates, with particular reference to hydrothermal vent organisms. The major conclusion is that thermal stability correlates positively with environmental temperature within the DNA regions encoding ribosomal RNA, but not throughout the genome. Increased thermal stability (based it is supposed on an increase in G-C content) of rDNA relative to total DNA confers protection to coding sequences which would otherwise be susceptible to damage during transcription. An increase in G-C content of rDNA will lead to an increase in G-C levels in rRNA which forms a major structural component of ribosomes, thus conferring increased thermal and chemical stability to these sites of amino acid synthesis within the cell.

In a series of laboratory experiments designed to create conditions under which the dispersal and feeding hypotheses of climbing in Hydrobia ulvae would predict opposing results, significantly larger numbers of snails climbed (a) food-bearing sticks than non-food-bearing sticks, (b) in 100% sea water than in 41% sea water, and (c) in the dark than in the light. The first two of these results are in accordance with the hypothesis that climbing is not a distinct behavioural activity but is merely normal crawling/browsing behaviour carried out in a vertical plane; they are in disagreement with the hypothesis that climbing is undertaken in order to facilitate dispersal away from unfavourable conditions. The third result is neutral in respect of the two hypotheses, but is explicable in terms that activity during the night is advantageous because of lowered rates of vertebrate predation.