The hippolytid genus Leontocaris includes eight species, all restricted to the deep sea (240–2182 m). Associations with deep sea coralline habitats were reported and are herein confirmed. Three Australian species were recorded at seamounts as were the specimens herein identified as L. smarensis sp. nov. These specimens were sampled at the South Mid-Atlantic Ridge (SMAR) by the Mar Eco project during 12 bottom trawls using a Sigsbee trawl. The SMAR is a seamount chain that rises from 4000 m depth, with mountains of 100–200 km wide and 14,000 km length. Leontocaris smarensis sp. nov. shows closest affinity to L. lar from the north-western Atlantic and L. yarramundi, from Australia and New Zealand. It differs from L. lar mainly in: (1) the scaphocerite distolateral tooth reaching the distal margin of the blade while clearly falling short in the latter species; and (2) the mandibular palp possessing three distal setae while setae are absent in L. lar. The new species differs from L. yarramundi in the number and disposition of dorsal teeth on rostrum and in the absence of an acute posterolateral spine on abdominal somites 4 and 5.

Five specimens of the penaeid genus Funchalia were found inside living Pyrosoma atlanticum taken off Tenerife. No such association has been noted previously. The largest of the Funchalia was an immature F. villosa; the other four were early post-larvae. Aspects of their morphology are described and compared with previous descriptions. They were probably also F. villosa.

The effect of different salinities on the marine snails Hydrobia ulvae and Hydrobia ventrosa (Mollusca: Prosobranchia) was studied in laboratory experiments. For juvenile snails, neither shell growth nor the strength of interspecific competition were affected by salinity within the range of 15–30 psu. In contrast, we found that larvae of H. ulvae were sensitive to salinity: survival was higher and the larvae were more active in higher salinity. The negative influence of low salinity on H. ulvae larvae may not be the only explanation of the complementary field distribution of the two species, since habitat separation is present in areas without spatial salinity variation.

We analysed 267 zooplankton samples collected in the South Brazilian Bight (SBB; 23–27°S) to determine whether hydroids, typically benthic, are common components of the pelagic SBB. Two species, Clytia arborescens, recorded for the first time in the Atlantic Ocean, and Clytia sp. were identified. While these planktonic hydroids were frequent or relatively so in shallow shelf waters (~23% of the samples <50 m isobaths, and 5% of the samples >100 m), abundances were low (up to 61 hydranths m−3) suggesting a low trophic impact. Such colonies are probably fragments of benthic colonies detached by storms and/or tides. Given the good condition of the coenosarc, existence of gastric content, and presence of reproductive structures, development of these species appears to be normal in the pelagic environment. Existence in the plankton may increase their capacity for dispersion.

The age and growth parameters of grey triggerfish, Balistes capriscus from the Gulf of Gabès, southern Tunisia, Mediterranean Sea, were estimated from the first dorsal spine sections of 463 specimens (206 males and 257 females), whose fork length was between 139 and 427 mm and the total weight ranged from 90.04 to 1967.41 g. The monthly percentage of specimens having a terminal translucent zone has indicated that the growth zone is formed once a year, during the cold season (February). The von Bertalanffy growth equations were: FL = 420.7 [1 − e−0.233(t + 0.123)] and FL = 417.0 [1 − e−0.238(t + 0.074)], for males and females, respectively. The longevity estimated was 13 years old for both sexes. The instantaneous mortality rates were estimated to 0.23 for males and 0.24 for females. The weight–length relationships of the grey triggerfish were Wt = 21.510−3 LF3.046 and Wt = 41.010−3 LF2.835, for males and females, respectively.

Multi-locus DNA fingerprinting was used to determine the degree of genetic relatedness within localized assemblages of the intertidal isopod, Jaera albifrons (Crustacea: Isopoda). This isopod has marsupial development, restricted adult vagility and specific habitat preferences, which will tend to isolate groups of animals on a shore and can potentially maintain the integrity of broods after release from the mother. Total genomic DNA was extracted from six individuals from each of ten ‘rock-populations’ in the South Wales area, restricted with Rsal, Alulll and Haelll endonucleases, and probed using a (TCC)5 oligonucleotide probe. Band-sharing analysis of the fingerprint patterns indicated significantly higher genetic relatedness within rock-populations (mean within rock-population band-sharing value = 0–374 ±0–023 SE) than between (maximum between rock-population band-sharing value = 0–301 ±0033), and at a level that equates to a relatedness between individuals within rock-populations of slightly below half-sibling status. The significance of such findings, in terms of the potential for localized inbreeding and population genetic structure, is discussed.

Phenoloxidase (PO) has been shown to be present in both invertebrates and vertebrates, yet little is known about the PO in Branchiostoma belcheri tsingtauense. The present study demonstrated that the PO activity existed histochemically the epithelial cells of the gill bar and intestine of adult animal, producing brown to black melanin deposits. Ultrastructural examination revealed that PO reaction products were localized in the cytoplasmic granules of the epidermal cells, the epithelial cells of gill bar and intestine and most of them were electron-dense and homogenous. Frequently, the PO reaction products were also observed in the secondary lysosomes.  The mucus from the body surface had little antibacterial activity against Escherichia coli, but it enhanced the antibacterial activity of L-dopa and the enhancement was suppressed by PTU, a PO specific inhibitor. This indicates that the active material inhibiting the E. coli growth in the mucus is PO.

the olfactory organ in small and large juveniles of the tropical yellowstriped reef cardinalfish apogon cyanosoma, collected from the wild (total length [tl] range=17–32 mm, mean=25 mm) was examined by scanning electron microscopy. the olfactory organ consisted of two bilaterally radial rosettes in each fish. they were oval-shaped, located medioventrally, one in each of the olfactory chambers. in small juvenile a. cyanosoma the rosette comprised six lamellae, three on each side of a midline raphe while large juveniles had eight lamellae, four on each side. the lamellae had a continuous cover of cilia, except for the margins. in small juvenile a. cyanosoma (tl mean=24.3 mm) only microvilli were observed, whereas both microvilli and a few cilia, presumably from olfactory receptor neurons, were observed in large juvenile a. cyanosoma (tl mean=32 mm).

This article is a review of the genus Richtersia (Nematoda: Selachinematidae) with a key to species, genus diagnosis and lists of valid species. Two new Richtersia species from the Golfo San José and Golfo San Matías, Chubut province of Argentina are described: Richtersia bicornis sp. nov. is characterized by having two thorn structures after cuticular collar, and in total 32–40 longitudinal rows of spines arranged in eight groups in cervical region and precloacal spines similar in shape. Richtersia argentinae sp. nov. is characterized by the number of longitudinal rows of spines, amphid size and the precloacal spines configuration.

The reproductive biology, in response to temperature, season and copper, of a coastal population of opossum shrimps (Crustacea: Mysidacea) was measured. The reproductive pattern for Praunus flexuosus at Keyhaven (west Solent, southern England) has maximum activity in April and maximum reproductive effort in May/June. Increasing temperature decreases incubation time and the reproductive pattern is adapted to compensate for temperature effects. Reproduction was inhibited with copper exposure. Fertilization of the eggs did not occur in any copper treatment (5, 25, 75, 200 μg l−1 copper added). Brooding females exposed to copper suffered a high abortion rate. The inability to produce broods, appears to be a long-term effect, as specimens previously exposed to copper did not produce any broods after two weeks in seawater controls.

The aim of the present investigation is a thorough inventory of the Harpacticoida (Copepoda) of the Portuguese islands Madeira and Porto Santo to provide a basis for comparisons of the harpacticoid faunas of successive elevations of the so called ‘Madeira Hot Spot Track’. Quantitative samples from 10 sampling locations at the coastlines of both islands were analysed (eight from Madeira and two from Porto Santo) and revealed a total of 27 families of Harpacticoida. Nine of the families were determined on species level comprising 43 species of which 31 were new to science. Comparisons of the family and species assemblages at the different Madeiran sampling locations indicate strong habitat heterogeneity as well as differences of the southern from all remaining locations. The sampling locations at the north and east coast are predominately characterized by interstitial taxa, those of the south coast by more robust burrowing or epibenthic taxa. Furthermore the two easternmost sampling locations of Madeira show clear similarity in terms of their harpacticoid assemblages with the sampling locations of Porto Santo. Eighty-eight per cent of the determined species of Porto Santo occur at the coast of Madeira as well (predominately at the easternmost sampling locations) indicating dispersal of Harpacticoida between both islands.

Current literature considers that Nasolamia velox has a limited distribution along the coastline of the Eastern Pacific with sporadic sightings in the Galapagos Archipelago. This study provides evidence of the occurrence of this species at the Revillagigedo Archipelago (18°99′186″N 112°08′44″W), Mexico, using acoustic telemetry and videos taken from 2014 to 2016. We report here movements from a coastal location (National Park Cabo Pulmo) to a group of oceanic islands (Revillagigedo Archipelago) by one single individual, supporting the idea of the potential connectivity of sharks between the Gulf of California and the Revillagigedo Archipelago. This report extends the known distribution of N. velox to 400 km off the mainland coast of the Americas, thereby increasing the knowledge of the distribution of a species commonly reported in fishery landings of the Eastern Pacific.

Four new species of the genus Desmodora are described from the South Atlantic off the south-eastern coast of the State of Rio de Janeiro, Brazil. Desmodora porosum sp. nov. is characterized by sexual dimorphism in the shape of the amphids, which are closed loop-shaped in males, and multispiral amphids in females. A case of intersexuality was found in the species, with a functional female gonad. Desmodora profundum sp. nov. is characterized by filiform spicules with a capitulum, buccal cavity with one dorsal and one small ventral tooth, tail cylindrical with a terminal spinneret, and wider rings in the neck region than on the rest of the body. Desmodora veronicae sp. nov. possesses cryptospiral amphids, a buccal cavity with one dorsal tooth and two smaller ventral teeth, 14 tubular pre-cloacal supplements, two ventral cuticular protruberances on the tail, and curved spicules with a capitulum and velum. Desmodora curvatum sp. nov. has the cuticle finely striated, without somatic setae, multispiral amphids, and a gubernaculum without apophysis, curved dorsally with the tip directed toward the end of the body.

Heart urchins (Echinoidea: Spatangoida) are considered infaunal, deposit feeding sea urchins that utilize the surrounding sediment as a source of nutrients. Sediment occupies most of the digestive tract lumen but never enters the gastric caecum, a prominent structure that is filled with a transparent fluid. The aim of this study was to shed light on the nature of the fluid found inside the gastric caecum of a well-studied spatangoid species, Echinocardium cordatum. Our conclusions are based on a three-step-approach: firstly, by following the movement of dyed seawater from the mouth up to the caecal lumen; secondly, by comparing the osmolarity of various body fluids; and thirdly, by describing the particulate content of the gastric caecum. In addition, we employed magnetic resonance imaging (MRI) to reveal the absence of sediment within the gastric caecum. Our osmolarity measurements show that the coelomic fluid is significantly more concentrated than the caecal fluid, which in turn has an osmolarity similar to seawater. MRI reveals that the gastric caecum, in contrast to the rest of the digestive tract, is always devoid of sediment. Light and electron microscopy observations reveal the presence of a variety of detrital particles suspended in the caecal fluid that are identical to those occurring in seawater sampled over the seafloor. We argue that the fluid filling the gastric caecum must be predominantly seawater, and we propose a scenario that explains seawater circulation in E. cordatum. In this context, the gastric caecum could act as an internal trap for suspended particulate organic matter. We hypothesize that spatangoid sea urchins could have adopted internal suspension feeding as a secondary feeding mode in addition to deposit feeding.

The poorly known sponge species Axinella vellerea (Topsent, 1904), Acarnus levii (Vacelet, 1960) and Haliclona poecillastroides (Vacelet, 1969) are reported from bottom-trawl samples off the Balearic Islands, Western Mediterranean. A re-description is provided for all three species and the Folmer fragment of cytochrome oxidase subunit I (COI) obtained for A. levii and H. poecillastroides. This is the second report of A. vellerea in the Mediterranean, the first time that A. levii is reported outside Corsica and the first time that H. poecillastroides is documented outside the Gulf of Lion, France. The systematic allocation of A. levii and H. poecillastroides is discussed based on a COI phylogenetic analysis and morphology. The poorly understood phylogeny of the Haplosclerida does not permit us to find a proper allocation for H. poecillastroides, although its current position in the genus Haliclona or the family Chalinidae is not defensible. On the other hand, A. levii currently fits best in the family Microcionidae, and seems related to some Clathria species with mixed features between Clathria and Acarnus. Considering that the species of the genus Acarnus shares a strong synapomorphy (the possession of Cladotylotes), it is plausible for all Acarnus species to be Microcionids. We conclude that H. poecillastroides needs to be reallocated to a new genus: Xestospongia poecillastroides comb. nov. (Petrosiidae). However, a reallocation of A. levii is not advisable for the moment, as this would imply major systematic changes such as the reallocation of the whole genus Acarnus to Microcionidae, and the redescription of Microcionidae and Acarnidae.

Black scorpion fish (Scorpaena porcus) is an important species for both artisanal and industrial fisheries in the Turkish Black Sea, with 306 tonnes landed in 2017. The diet composition of this species was investigated through the examination of their stomach contents. A total of 621 S. porcus (ranging from 12.79–765.5 g) were caught by trammel net in the south-eastern Black Sea (Turkish waters) from December 2015 to November 2016. The importance of prey items in the diet of S. porcus was assessed using the Index of Relative Importance (%IRI). Overall, the dominant species was the isopod Idotea balthica (52.8%IRI) followed by decapods (38.5%IRI) and teleosts (8.7%IRI). Seasonal variations in the diets were observed, with isopods predominant in autumn (>85%IRI), teleosts in winter (>77%IRI) and decapod crustaceans (>78%IRI) in spring and summer. The modified Costello's graphical analysis evinced a specialist feeding strategy for S. porcus during winter, spring and autumn while a shift to generalistic feeding strategy was exhibited in summer by a limited number of S. porcus individuals.

The radular activity of dogwhelks, Nucella lapillus, drilling mussels, Mytilus edulis, was monitored by piezoelectric transducers and recorded by an automatic digital system. In this way, for the first time, the drilling behaviour of dogwhelks was analysed in detail. Radular activity was similar to that previously recorded for limpets, each radular stroke (rasp) being formed by a sequence of 1–8 unit events, each probably corresponding to the application of one row of radular teeth on the substratum. During drilling, radular rasping followed a consistent pattern, each bout of radular rasping (lasting about 6–8 min) being followed by a period of radular inactivity (lasting about 35 min), when chemical dissolution is probably applied. The periodicity with which rasping was applied decreased during the drilling sequence (from about 25 min in the first quarter of the drilling process to about 40 min in the last quarter), together with a decrease in the rasping rate, i.e. number of radular rasps per min (from about 12 to about five rasps per min). Accordingly, the total number of radular rasps recorded during the first quarter of the drilling time was higher than during the other quarters (from about 3000 to about 500 rasps). The role of the radula in shell penetration was therefore rather extensive, accounting, during the first quarter of the process, for about 34% of drilling time. The results are discussed in relation to studies of chemical dissolution and mussel shell ultrastructure.

The Indian Western continental shelf (IWCS) is amongst the most productive regions of the world, being noteworthy for upwelling (south-west monsoon) and downwelling (north-east monsoon) that tunes the water biogeochemistry. The present study provides baseline information on temporal variation of in situ copepod gut pigments from IWCS. The copepods were collected between November 2011 and October 2013 and gut pigment contents and composition were estimated using the gut fluorescence method. Results revealed that copepods procured high gut pigment content in monsoon that coincided with ambient water pigment credited to discrete upwelling. Fluorometric analyses of copepod orders revealed presence of gut chlorophyll a (Chl a) throughout the study with highest gut Chl a (0.31 ± 0.25 ng copepod−1; N = 21) and total gut pigments (2.01 ± 2.15 ng copepod−1; N = 21) recorded in Calanoida. Consecutively, Calanoida and Poecilostomatoida chiefly consumed autotrophic biomass that was evident from presence of canthaxanthin and astaxanthin as dominant gut pigments. Interestingly, the marker pigment of Cryptophyceae was present only in Calanoida during monsoon and post-monsoon. Collectively these results conclude that copepods predominantly showed omnivory with discrete temporal variability by grazing upon autotrophic biomass that in turn probably supports the fishery.

Several characteristics of Totoaba macdonaldi Perciformes: Sciaenidae, including migratory movements along temperature gradients make it vulnerable to oxidative stress. Oxidative stress can also be associated with reproduction. The objectives of the present study were to examine oxidative stress indicators in liver of totoaba throughout the seasons (spring, autumn and winter), and the associated fluctuations in superficial sea temperature (SST, °C), as well as to evaluate possible variations between sexes and reproductive maturity stages. A total of 173 liver samples from totoaba captured in the Gulf of California, Mexico, were obtained from April 2010 to February 2013. Superoxide radical production (O2•−), lipid peroxidation (TBARS) levels, and activity of antioxidant enzymes; superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR) and glutathione S-transferase (GST) were quantified spectrophotometrically. Generalized linear models (GLM) were used to determine which factors contribute to explain O2•− production and TBARS levels. The significant predictive variables were the seasons, which were significant in all applied models, as well as SOD and CAT activities. In general, enzyme activity was higher in immature totoaba; this was not seasonally modified. Low temperatures in winter were associated with high O2•− production and TBARS levels, particularly in totoaba that are not yet reproductively mature. Seasonal changes in sea surface temperature did not affect the oxidative stress indicators in mature totoaba (both males and females); this suggests that mature totoaba are less sensitive to temperature changes from an oxidative stress perspective.

The toxicity of produced formation water (PFW) originating from four natural gas production platforms located in the Adriatic Sea (Italy), and of seawater samples collected near these installations is assessed by means of bioassays with Brachionus plicatilis, with the brine shrimp Artemia franciscana and with Paracentrotus lividus. The toxicological response of these specimens was evaluated in order to identify the most sensitive one, in the consumer compartment, and to design a bioassay battery specific for samples collected in the surroundings of a gas platform. Larval mortality of rotifers, larval immobilization of crustaceans, fertilization success/failure (sperm cell test) and larval (pluteus) development success/failure (embryo toxicity test) of sea urchins were taken as ecotoxicological endpoints. The PFW sampled on two platforms resulted toxic, while no toxicity was recorded in seawater samples collected in the vicinity of the platforms, even in coincidence with the PFW discharge operations. The species and bioassays employed have shown different responses to PFW: P. lividus turned out to be more sensitive than A. franciscana and B. plicatilis. In particular, the embryo toxicity test showed a higher toxicity than the sperm cell test.