A new species of Orthonectid, Rhopalura granosa from Heteranomia squamula L., is described. The female is fusiform, and about 190 to 230μ, long, and 55 to 75μ broad. The male is also fusiform, but less than half the size of the female, being only 87 to 95μ, long and 20μ broad. R. granosa is distinguished from all other known species of Rhopalura by the presence in the male of large refringent bodies in the anterior cone, and in the first row of cells of the second ring. The male of R. ophiocomce Giard, a species closely allied to R. granosa, has the refringent bodies in the cells of the second ring only.

The notodelphoid copepods parasitic within Ascidians have been generally ignored for a long time. In May 1932 the present writer collected a considerable number at Millport Marine Biological Station, and was amazed at the frequency with which they occur. It may be that the Clyde area is especially favourable to their development, or it may be that the season was particularly good, for about thirty specimens were collected of ten species, of which at least one—the subject of the present paper—was new to science. If this abundance of forms is indeed usual, it is difficult to understand why records are not more frequent, and it would be interesting to learn how frequently these fascinating and aberrant forms are lost in the course of class dissections of their hosts.

According to E. T. Browne, 1899, Stephanomia bijuga (Delle Chiaje) (syn. Cupulita sarsii Haeckel and Agalmopsis elegans Sars, partim) belongs to the surface Atlantic fauna. It has been recorded at Valencia from March to November, and while suffering badly from the destructive power of gales it must occur at times in enormous numbers, for in November, 1898, tow-nets were taken that were full of isolated pneumato-phores. Into the more confined waters of the English Channel, however, it penetrates apparently very rarely, the only record being that of a single specimen taken a mile or two out from Plymouth Sound in March, 1902.

Recent equations for calculating the osmotic coefficient of sea water from the properties of the component single-electrolyte solutions are discussed. Two equations are introduced that together provide accurate predictions of the osmotic coefficient of sea water for ionic strengths up to 4 M (equivalent to a fivefold concentration of standard sea water). Since they take into account the detailed solution composition these equations should be useful for calculating the osmotic coefficients of estuarine waters and of biological salines where procedures based on curve fitting to standard sea-water data may be inapplicable. Extensions of the calculations to cover a wide pressure and temperature range are discussed in some detail.

Stomatogenesis of the marine scuticociliate Metanophrys sinensis, collected from a molluscan culturing pond in Qingdao, China, was studied using protargol impregnation method. The morphogenetic sequence develops in the proter: the remnant of parental paroral membrane gives rise to the paroral membrane and scutica, and the three parental membranelles were inherited. In the opisthe: the paroral membrane, membranelles 1, 2 and the scutica originate from the parental paroral membrane, while parental scutica gives rise to the membranelle 3. This suggests that M. sinensis has a relatively similar morphogenetic pattern to the members of the genus Uronema.

Mesophotic ecosystems have been relatively poorly studied in the Indo-Pacific and in particular within the Coral Triangle region. Here we used a mini-ROV to explore the changes in major benthic groups at two sites (~200 m apart) in the Wakatobi Marine National Park, SE Sulawesi, Indonesia spanning shallow water coral reefs (5 m) to deeper water mesophotic ecosystems (80 m). We found very similar patterns at both sites where coral cover peaked at 15 m, declined rapidly by 30 m, and was virtually absent at 50 m. As coral declined there was a marked increase in sponges, soft corals and other encrusting organisms (including ascidians, bryozoans, tubeworms, gorgonians and molluscs). Importantly, our results differ from most previous studies in other geographic locations where hard corals extend much deeper. It is unclear what drives this difference but it may be related to higher levels of turbidity and therefore reduced light penetration in the Wakatobi compared with other areas, which limits the vertical extent of coral development.

Garfish (Beloniformes, Belonidae) are surface-dwelling, predatory fish characterized by elongate bodies and long beak-like jaws. Most are oceanic, but some species occur in estuaries and rivers. There are thirty-two species worldwide (Collette, 1982), of which until recently only one, Belone belone (L.) was known to be present in the waters of northern Europe. However, the existence of a second species, Belone svetovidovi Collette and Parin, was reported by Dorman (1984) from the south coast of Ireland. To date, thirty-one specimens of this fish have been captured in Courtmacsherry Bay, Co. Cork. This paper gives some details of these fish and how they may be distinguished from B. belone.

The morphology and infraciliature of two planktonic marine ciliates, Cyclotrichium cyclokaryon, type species of the genus and C. taniguchii sp. nov. were investigated on live and protargol-impregnated specimens collected from the Jiaozhou Bay at Qingdao, China. Based on the present as well as previous studies, an improved diagnosis for the poorly defined genus Cyclotrichium is suggested: Didiniidae with ovoid to barrel-shaped body; cell-surface densely ciliated except in the domed proboscis region; anterior ends of kineties with long cilia forming one circumoral wreath of pectinelles; one circumoral kinety composed of a zig-zag structure; dorsal brushes absent. Cyclotrichium taniguchii is distinguished from its congeners by the combination of the following features: ellipsoid body shape, marine habitat, details of ciliature, and lack of a posterior tuft. Based on the characters of the ciliary pattern, a new genus, Dicyclotrichium gen. nov., with the type species Dicyclotrichiumsphaericum comb. nov. is established. The new taxon differs from Cyclotrichium by having two wreaths of pectinelles. Two known morphotypes are suggested to be assigned into this genus: Dicyclotrichium faurei comb. nov. [basionym: Askenasia faurei] and D. humilis comb. nov. [basionym: Askenasia humilis].

Synisoma albertoi sp. nov. (Isopoda: Valvifera: Idoteidae), is described and illustrated from specimens collected in the Strait of Gibraltar (southern Spain). The new species can be distinguished from all other species of the genus, with the exception of S. bellonae and S. raqueliae, by the fusion of the flagellar articles of the antenna. It is easily distinguishable from both S. bellonae and S. raqueliae by the presence of a tubercle on the cephalon; these three species also differ in the morphology of pleotelson, pereopods and appendix masculina. A key to the known species of Synisoma is provided.

Parablennius ruber, the red or Portuguese blenny, is reported from the British Isles. This species has recently been revalidated as separate from P. gattorugine and this, together with confusion about the field identification characteristics which distinguish the two species, is likely to have resulted in it being under-recorded. Parablennius ruber was found to be fairly widespread on the exposed west coasts of the Republic of Ireland and Scotland (22 records), with additional records from the Isles of Scilly (3 records) and Northern Ireland (1 record). One record was made of egg guarding. Most records were from exposed areas of bedrock and boulders, between 15 and 30 m in depth. Field identification characteristics which distinguish between P. ruber and P. gattorugine are given. Given that its original description was from Ushant in 1836, it is unlikely that P. ruber is a fairly recent addition to the British fauna as a result of increased water temperatures. However, given its habitat, the fairly recent advent of sampling by SCUBA diving is likely to have increased the potential for sightings. The growth of SCUBA diving and the increase in the use of underwater digital photography are likely to result in a better knowledge of its distribution.

Amphioxi represent the evolutionary link between vertebrates and invertebrates. For this reason, research dealing with these animals has been focused mainly on embryological and anatomical studies. Out of 30 described species, only one, Branchiostoma elongatum, is known to inhabit shallow sandy bottoms along the Humboldt Current System (HCS) of Chile and Peru. The population dynamics of B. elongatum from northern Chile was studied between February 2008 and January 2009, and the results were compared with other species within the genus Branchiostoma inhabiting distinct ecosystems. Mean abundance of B. elongatum was low (158.6 ind m−2) in comparison with the abundance of other species within Branchiostoma. Although the gametogenic activity was continuous, a clear spawning event was observed between August and October, which seemingly produced a recruitment pulse during the summer and consequently a simultaneous increase in population density and decrease of mean length during that period. Growth of B. elongatum was best fitted to the seasonalized von Bertalanffy growth function (K = 0.45 year−1 and L∞ = 64.6 mm), with faster growth during summer–autumn. Growth performance (Ф′ = 3.273) was high in comparison with other species within the genus. Mortality of B. elongatum (Z = 1.075 year−1) was well fitted to the single exponential model (r2 = 0.92). The annual total production of B. elongatum reached 0.68 g ash-free dry mass (AFDM) m−2 and the annual mean biomass was 0.56 g AFDM m−2, which determined a production to biomass ratio of 1.22. The huge productivity of the HCS was not reflected in a high abundance and biomass of B. elongatum. However, this species displayed a high growth efficiency and P/B ratio that are comparable to those of other Branchiostoma inhabiting highly productive ecosystems.

There is a paucity of information on the cetacean fauna of Guinea-Bissau in West Africa. We compiled records published in the literature and novel unpublished sighting data (2008–2014) to examine the occurrence and distribution of cetacean species. At least 10 species were verified to occur in Guinea-Bissau waters, of which eight were documented from a small number of sightings, whaling captures or skeletal remains. By far the most frequently recorded species were the common bottlenose dolphin (Tursiops truncatus) (N = 146) and the Atlantic humpback dolphin (Sousa teuszii) (N = 110). These two species were sympatric in distribution, both being found throughout coastal waters from the northern regions of Canal de Jeta and Rio Mansôa south to the Rio Cacine and around the Arquipélago dos Bijagós. However, differences were apparent in their finer-scale distribution and in the distance of sightings from shore, with bottlenose dolphin sightings generally occurring further from shore (and especially in the region of the Canal do Gêba) than Atlantic humpback dolphins. Sightings indicate that both species likely inhabit Guinea-Bissau waters throughout the year. Dedicated systematic cetacean survey work is urgently needed in coastal Bissau-Guinean waters in order to ascertain the abundance, spatio-temporal distribution, population structure and causes of mortality of bottlenose and Atlantic humpback dolphins, particularly given the Vulnerable conservation status of the latter species. Clarification of the status of cetaceans in offshore waters requires survey effort throughout the Guinea-Bissau EEZ.

A systematic survey of the sponge fauna of the Aegean Sea has been carried out. Twenty-eight stations located in the Aegean Sea were explored and 59 species of Demospongiae were collected from this particular area, which covers a broader geographical area of the Aegean and Cretan Seas. Some of the species found are poorly known for the Mediterranean fauna, like Cerbaris curvispiculifera and Spongosorites flavens, which are reported for the first time in the Aegean Sea and generally in the eastern Mediterranean. The species Axinyssa michaelis sp. nov. (Halichondriidae: Halichondrida) is new to science. In this paper, a description of the new species is presented along with the description of the first recorded species in the Aegean Sea. In addition to the taxonomic description of the species, some ecological data and a distribution pattern are also presented.

Larvae of Ibla cumingi from Daya Bay, China were cultured in the laboratory. Larval development includes six naupliar stages and a non-feeding cypris stage following the ground patterns of cirripeds. Larvae reached the cypris stage in nine days at ∼25°C after hatching. Morphological features including the cephalic shield, frontal horns, labrum, abdominal process, antennules, antennae and mandibles in all nauplii were described and illustrated using light microscopy. A full morphological description of cyprid larvae was provided using scanning electron microscopy. Attempts were made to compare the difference between the larval development model of I. cumingi and that of Ibla species.

The new mangrove barnacle, Fistulobalanus sumbawaensis sp. nov. from Sumbawa Island, Indonesia shares the common morphological characteristics with the subfamily Amphibalaninae in having a shell wall of six, porous compartmental plates; radii solid; alae not cleft; basis calcareous, tubiferous in single layer. This new species belongs to the genus Fistulobalanus mainly in having parietal tubes arranged in two or more rows; primary tubes with transverse septa; subsidiary tubes formed between the primary septum and outer lamina. In particular, the new species is similar to F. patelliformis in the shape of the shell, the transverse section of subsidiary tubes, the tergum and some characteristics of trophi and the cirri. However, this new species is easily distinguishable from all members of the genus Fistulobalanus in having no coloration or striations on the external surface of the shell, subsidiary tubes only appearing inside the ribbed part of the shell, and the scutum having a short adductor ridge.

The ultrastructure of sperm of an acochlidian opisthobranch is described for the first time in detail, in the tiny, gonochoristic Microhedyle remanei (Microhedylidae) from Bermuda. Transmission electron microscopy (TEM) shows the spermatozoa of M. remanei sharing many plesiomorphic features with opisthobranch gastropods, such as having an apical spiral nucleus with a basal invagination filled with a bell-shaped centriolar derivative; there is a single glycogen helix embedded into matrix and paracrystalline material. Sperm of M. remanei are characterized by possessing a strongly helically coiled nucleus with up to five keels terminating into one very prominent and intertwined keel. The sperm midpiece shows the glycogen helix which is very densely arranged. This clearly differs from Hedylopsis ballantinei, a member of the related acochlidian family Hedylopsidae, where three glycogen helices with different lengths and a probably much shorter nucleus are present. This variation among acochlidian sperm may be phylogenetically relevant and may be related to special acochlidian reproductive features such as sperm transfer via hypodermic injection or dermal fertilization via spermatophores.

The original descriptions of species of the genus Ptychodiscus are discussed. Recent material is examined both alive and preserved. It is concluded that the only valid species is Ptychodiscus noctiluca Stein. Ptychodiscus carinatus Kofoid, P. inflatus Pavillard and Diplocystis antarctica Cleve are all synonymous with this species.

During studies in 1972 on the setation and development of the secondary sexual characters of the Norway lobster, Nephrops norvegicus (L., 1758), Foraminifera were observed attached to the pleopods of a mature male (carapace length 2.47 cm). On subsequent examination of the prepared material with a scanning electron microscope it was found that the Foraminifera were attached to one of the first pair of pleopods. Three individuals were observed, all of which were attached to the same pleopod on the inner surface near the tip. No further specimens of Foraminifera were encountered during detailed anatomical studies of more than 30 specimens of N. norvegicus.

The population composition and aspects of the reproductive biology of 452 blackmouth catsharks, Galeus melastomus were investigated. The sharks were incidentally caught off the North-Western Aegean, the Eastern Corinthian and Northern Euboean Gulfs by commercial bottom trawlers and longlines at depths between 200 and 500 m. The overall sex ratio (1:1.1 females:males) was not different from the theoretical unit (1:1). No differences in the sex ratios were detected among seasons, areas or depth strata. Significant differences in the population structure regarding different maturity stage proportions at different seasons, fishing areas and depths, were observed. The sampled population mainly consisted of immature catsharks (77%), predominantly trawled off the NW Aegean and Corinthian Gulf during winter and autumn. Fifteen per cent of the samples, mainly captured in spring and summer off the N Euboean Gulf, were mature. Eight per cent of the specimens was found to be maturing. Higher frequencies of heavier female individuals were observed. Based on the maturation ogives and the total lengths (TL) for each sex, using logistic regression which presented sex-related differences, male Galeus melastomus achieved maturity at 433.6 mm while females at 483.5 mm. The number of egg capsules in the oviducts spanned from 1–12 per female with sizes varying from 38 × 14 mm to 55 × 20 mm. This is the first study investigating the demography and aspects of Galeus melastomus reproduction in the Eastern Mediterranean.

Macroalgal fouling communities are potentially useful as bioindicators in environmental monitoring as they are considered to be sensitive to changes in environmental conditions and the use of artificial substrata facilitates the implementation of standardized sampling strategies. The response of macroalgal fouling communities on buoys to changes in water quality was investigated with a view to the possible utilization of these assemblages in environmental monitoring programmes. Seven study sites were selected based on previously collected environmental data and Principal Components Analysis (PCA) was used to order sites according to beam attenuation coefficient (BAC) and concentration of dissolved nitrates and phosphates, relative to a minimally impacted reference site. At each site, all fouling macroalgae were collected from 10 buoys of standard shape and size, and were identified to the lowest possible taxonomic level. Species composition and species dominance were highly variable among impacted sites, indicating that qualitative aspects of community structure may not be useful as indicators of changes in water quality. However, higher levels of nutrient enrichment and turbidity were associated with lower macroalgal species richness, lower overall abundances, and decreased diversities, and therefore these quantitative aspects of community structure are potentially useful as indicators of environmental change. Intermediate levels of turbidity and nutrient enrichment were associated with lower evenness, but did not influence species richness, suggesting that macroalgal abundances respond to changes in environmental conditions before species replacement occurs.