Caligus solea n. sp. (Copepoda: Caligidae) parasitic on the common sole Solea solea (Linnaeus) from the north-eastern Mediterranean off the Turkish coast

A new species of caligid copepod, Caligus solea n. sp., is described from the common sole Solea solea (Linnaeus) caught off the north-eastern Mediterranean coast of Turkey. Both sexes of the parasite were collected from all over the upper body surface of its host. The new species belongs to the macarovi-group of species as established by Boxshall & Gurney (Bull Br Mus (Nat Hist) (Zool), 39:161–178, 1980), with which it shares the following four characters: (i) leg 4 with two-segmented exopod, distal segment carrying three apical spines but no lateral spine; (ii) distal exopodal segment of leg 1 with three plumose setae posteriorly plus four distal margin elements, spine 1 naked, spines 2 and 3 with accessory process and spine 4 about twice length of the others; (iii) females with one-segmented abdomen while males with two-segmented abdomen; (iv) male maxilliped with myxal process opposing the tip of the subchela. However, the new species differs from its congeners within the macarovi-group in the number of sensillae on each papilla on and around the postantennal process, and also in the absence of serrations along the distal margin of the maxilla. This is the twenty-eighth species of Caligus to be reported from the Mediterranean Sea.     

<Emphasis Type="Italic">Caligus fajerae</Emphasis> n. sp. (Copepoda: Caligidae) parasitic on the Pacific sierra <Emphasis Type="Italic">Scomberomurus sierra</Emphasis> Jordan &amp; Starks (Actinopterygii: Scombridae) in the Pacific Ocean off Mexico

A new species of parasitic copepod, Caligus fajerae n. sp. (Caligidae), is described from Scomberomorus sierra Jordan & Starks (Scombridae) caught off the northwestern coast of Mexico. The new species morphologically resembles Caligus cybii Bassett-Smith, 1898, Caligus kanagurta Pillai, 1961, Caligus pelamydis Krøyer, 1863 and Caligus robustus Bassett-Smith, 1898, all of which have been reported from scombrid hosts. Caligus fajerae n. sp. differs from these species by having spinules on the abdomen and caudal ramus, two processes on the proximal antennulary segment, fine striations on the claw of the antenna and maxilliped, a stouter and more recurved maxillulary dentiform process, shorter tines on the sternal furca, two additional patches of spinules on the distal endopodal segment of leg 2, a sclerotised lobe on the anteromedian surface of the leg 3 protopod and serrations on both margins of the first exopodal spine of leg 3. Analysis of the DNA sequences of the mitochondrial cytochrome c oxidase subunit 1 gene for Caligus fajerae n. sp. and 28 congeners, including C. pelamydis and C. robustus, showed that the new species grouped with Caligus belones Krøyer, 1863 (with 20% divergence), a species known to occur predominantly on needlefishes. Caligus fajerae n. sp. is the fifth species of Caligus reported from S. sierra. An updated host-parasite list for Caligus spp. on scombrids is provided.     

Effect of temperature and salinity on the gastric evacuation of juvenile sole Solea solea and Solea senegalensis

The juveniles of Senegal sole, Solea senegalensis, Kaup 1858, and common sole, Solea solea (Linnaeus 1758) concentrate in estuarine and coastal nurseries of widely differing temperatures and salinities. Yet, little is known about the effect of these physiologically important variables on the gastric evacuation rates of these species. Gastric evacuation experiments were performed on juveniles of S. senegalensis and S. solea. Three temperatures were tested, 26, 20 and 14°C at a salinity of 35‰. A low salinity experiment was also carried out at 15‰, at 26°C. Experimental conditions intended to reflect conditions in estuarine and coastal nurseries where juveniles of these species spend their first years of life. The relation between stomach contents and time was best described by exponential regression models for both species. An analysis of covariance (ancova ) was performed in order to test differences in evacuation rate due to temperature and salinity (slope of evacuation time against stomach contents) for each species. While increasing temperature increased evacuation rates in both species (although not at 26°C in S. solea), the effect of low salinity differed among species, leading to a decrease in gastric evacuation rate in that of S. senegalensis and an increase in S. solea. Differences in gastric evacuation rate between species were related to its metabolic optimums and to its distribution in the nursery area where fish were captured. Implications for the habitat use of estuarine and coastal nurseries are discussed.     

Genetic and morphological analyses of tub gurnard Chelidonichthys lucerna populations in Turkish marine waters

Genetic and morphological structure of tub gurnard Chelidonichthys lucerna populations in Turkish marine waters were investigated with mtDNA sequencing of 16S rRNA and morphological characters. C. lucerna samples were collected from the Black Sea, Marmara, Aegean and northeastern Mediterranean coasts of Turkey. The lowest genetic diversity was found in the northeastern Mediterranean (Iskenderun Bay) population, while the highest was in the Marmara population with overall average value of genetic diversity within populations. A total of 14 haplotypes was found, and the highest haplotype diversity was in the Black Sea whereas the lowest was in the northeastern Mediterranean population (Iskenderun Bay). The Black Sea and Iskenderun Bay populations showed the least genetic divergence (0.001081), while the highest was between the Marmara Sea and northeastern Mediterranean (Antalya Bay) populations (0.002067). Pairwise comparisons of genetic distance revealed statistically significant differences (P < 0.05) between the Marmara and both the Aegean and northeastern Mediterranean (Antalya Bay) samples. Neighbour joining tree analyses clustered the northeastern Mediterranean populations (Antalya Bay and Iskenderun Bay) as genetically more interrelated populations, whereas the Aegean Sea population was clustered as most isolated one. Discriminant function analysis of morphological characters showed that only the Black Sea population is differentiated from the other populations.     

Distribution patterns of Batrachium communities in Mediterranean hard waters

The greatest number of Batrachium plant-communities is reached in base-poor waters of SW Europe where most Batrachium species develop laminar leaves. In contrast, base-rich waters of the Western Mediterranean are characterized by few Batrachium communities and by the only one Batrachium species present in the area with only dissected leaves. This work focused initially on studying the water ecology of Iberian Batrachium communities' developing in hard waters in order to seek to what extend the water physical–chemical gradient determines the occurrence of heterophyllous or homophyllous-dissected species. Floristic data and water physical–chemical data were analyzed using multivariate and comparative methods. We found two main types of Batrachium communities: community of Ranunculus trichophyllus – homophyllous and dissected species–, and community of Ranunculus penicillatus – heterophyllous species–. Alkalinity degree is the main factor separating both communities. Our results of a tentative survey on Batrachium composition in hard waters in the Eastern Mediterranean showed a wider range of physical–chemical water features as well as a greater number of Batrachium species with only dissected leaves in comparison to Western Mediterranean. We conclude that high alkalinity is related to the occurrence of Batrachium communities characterized by species with only dissected leaves in both the western and eastern parts of Mediterranean Europe.     

Comparative xenobiotic metabolism capacities and pesticide sensitivity in adults of Solea solea and Solea senegalensis

The measurement of enzymatic activities involved in xenobiotic biotransformation was carried out in adults of Solea solea and Solea senegalensis. The hepatic enzymes analysed were cytochrome P450 (CYP) related activities using eight fluorometric substrates and carboxylesterases (CbE). The conjugating activities of glutathione S-transferase (GST) and UPD-glucuronosyltransferase (UDPGT) were also assessed. Specific mammalian inhibitors were used as diagnostic tools for related activities of CYP1A (α-naphthoflavone; αNF), CYP2B6 and CYP2C19 (ticlopidine) and CYP3A4 (ketoconazole). The in vitro sensitivity to organophosphorous pesticides (OP) was tested in the S10 homogenate of brain (acetylcholinesterase-AChE) and liver (CbE). Furthermore, the pesticide chlorpyrifos oxon (CLPO) was used to explore the OP sensitivity of CbE of both species in two subcellular fractions (microsomes and cytosol), using two substrates. Overall, only two parameters confirmed species differences: EROD and cytosolic CbE being significantly elevated (p < 0.05) in the common sole, S. solea. A high inhibition of CYP1A related activities using several fluorometric substrates (ER, MR and CEC) after in vitro incubation with αNF confirmed all measure CYP1A1-related activities whereas ketoconazole was more specific for BFCOD (CYP3A4). Pesticide sensitivity was similar for brain AChE but hepatic CbE had a protective role that was species and pesticide dependent.     

Three species of <Emphasis Type="Italic">Caligus</Emphasis> Müller, 1785 (Copepoda: Caligidae) parasitic on <Emphasis Type="Italic">Caranx</Emphasis> spp. (Teleostei: Carangidae) off Taiwan

Three species of sea-lice (Siphonostomatoida: Caligidae) parasitic on marine fishes of the genus Caranx off Taiwan are reported. They are: Caligus fortis Kabata, 1965 on Caranx ignobilis (Forsskål); Caligus robustus Bassett-Smith, 1898 on Caranx sexfasciatus Quoy &; Gaimard; and Caligus inanis n. sp. on Caranx ignobilis. Caligus robustus is a widely distributed species, but this is the first report of C. fortis outside the Australian and Indian regions. The new species is distinguished from its congeners in lacking postantennal process and carrying a pair of tiny, tooth-like, sharp protuberances on the posterior margin of the cephalothoracic shield.     

A review of the culture potential of <Emphasis Type="Italic">Solea solea</Emphasis> and <Emphasis Type="Italic">S. senegalensis</Emphasis>

A number of scientific studies have investigated aspects of soles(Solea soleaandS. senegalensis) ecology, population genetics and biology in their natural environment, and the species have been extensively studied in captivity during the last decade. Studies on the genetic population structure of sole indicate that several distinct breeding populations exist within its distributional range in European waters. Recent studies suggest a phylogenetic relatedness ofS. soleaand S. senegalensis, being found as closest sister lineages in most reconstructions. However, studies on molecular genetics and morphological traits give diagnostic differences that consistently lead to their taxonomic separation at the specific rank. Studies show that sole spawn readily in captivity, and the buoyant, fertilized eggs are easily collected. Stocking density during maturation should be 1–1.5kg/m², and temperature should be kept above 16°C (S. senegalensis) or between 8 and 12°C (S. solea). In nature, the onset of spawning is related to a rise in temperature occurring during spring (March–June). Salinity should be kept constant around 33–35 and the fish reared under simulated natural photoperiod (LDN). In other cultured flatfish species, a change in the photoperiod is the key environmental signal used to manipulate and control maturation, but at present time there are no published work that verifies or contradicts this for either S. senegalensisor S. solea. Studies indicate that a mixture of inert and live food may increase the weaning success of sole fry, and this can be further enhanced by using attractants in the dry feed. Future experiments are needed to determine the ideal time to commence weaning and determine the minimum duration of this period. Studies on alternative feeding strategies are also required. The effect of temperature and photoperiod on juvenile growth has not been studied systematically in neither of the two species and the relative importance of a direct photoperiod effect on growth in sole therefore remains to be defined.     

A new species of Cucullanus Müller, 1777 (Nematoda: Cucullanidae) parasitic in the grey triggerfish Balistes capriscus Gmelin (Osteichthyes: Balistidae) off Rio de Janeiro,Brazil

Cucullanus brevicaudatus n. sp. (Cucullanidae) is described from the intestine of Balistes capriscus Gmelin (Balistidae) off Rio de Janeiro, Brazil. The new species can be differentiated from its congeners in the small body length, the shape of the gubernaculum, the particular size and morphology of the tail in both males and females, the arrangement of the caudal papillae, the narrow oesophageal base, and the eggs with rugged shells. In addition, the combination of some features, i.e. number of caudal papillae, spicule length, oesophagus/body length ratio, host family and geographical distribution, can help to easily distinguish the new species from other cucullanids. Considering these features, C. brevicaudatus differs from the species assigned to Dichelyne Törnquist, 1931 which exhibit morphological proximity with Cucullanus Müller, 1777. Regarding the life-cycle of cucullanid nematodes, available evidence suggests that some species are primarily heteroxenous using invertebrates (i.e. crustaceans, polychaetes) as intermediate hosts, but in other a histotrophic phase in the definitive host replaces the intermediate host.     

Tracking and mapping sun-synchronous migrations and diel space use patterns of Haemulon sciurus and Lutjanus apodus in the U.S. Virgin Islands

The spatially explicit diel movement patterns of fish using coral reef ecosystems are not well understood, despite the widespread recognition that many common species undergo distinct migrations to utilize different resources during night and day. We used manual acoustic telemetry coupled with global positioning technology to track the detailed spatially explicit daily movements (24 h) of multiple individuals of two common Caribbean fish species, Haemulon sciurus (bluestriped grunt) and Lutjanus apodus (schoolmaster snapper). Movement pathways and day and night activity spaces were mapped and quantified in a Geographic Information System (GIS). Directional sun-synchronous migrations occurred close to astronomical sunset and sunrise. Site fidelity within day and night activity spaces was high. Nine of twelve individuals exhibited overlap of day and night activity spaces and three fish (L. apodus) exhibited complete spatial segregation. Night activity spaces (H. sciurus: 11,309?±?3,548 m²; L. apodus: 9,950?±?3,120 m²) were significantly larger than day activity spaces (H. sciurus: 2,778?±?1,979 m²; L. apodus: 1,291?±?636 m²). The distance between sequential position fixes (step lengths) was significantly greater at night than day, indicative of nocturnal foraging and day resting behavior. Integrating acoustic telemetry, GIS techniques and spatial statistics to study fish movement behavior revealed both individual variability and some broader generality in movement paths and activity spaces suggestive of complex underlying behavioral mechanisms influencing diel movements.     

Identification of subpopulations in pelagic marine fish species using amino acid composition

The spatial stock complexity of marine fish species requires that population structure is taken into account in fisheries management. The aim of this study was to determine whether the amino acid composition (AAC) of the adult fish allows the identification of subpopulations within the stock. During a cruise in November 2003 along the entire Mediterranean coast of Spain, individuals were collected of the following pelagic species: Sardina pilchardus, Sardinella aurita, Engraulis encrasicolus, Trachurus trachurus, Trachurus mediterraneus, Scomber scombrus and Scomber colias. Individuals of S. pilchardus and E. encrasicolus were also collected from the waters of the Strait of Sicily in 2002 and 2003. The AAC of the fish eyes was seen to be species specific, and therefore, the differences in AAC among species may be based on inherited characters. Moreover, a clear differentiation was seen between the Spanish and Sicilian populations of S. pilchardus and E. encrasicolus. Furthermore, in the Spanish waters of the Mediterranean Sea, discriminant analysis revealed a substantial separation between the northern and southern subpopulations of S. pilchardus, S. aurita and E. encrasicolus. Temporal variations in AAC within species in each area were lower than the spatial variations observed among areas for each species, probably reflecting the influence on the AAC of the contrasting environmental characteristics of each area. Our results indicate that the ACC of the eyes in adult fish is a good tool for discriminating among subpopulations in pelagic marine fish species.     

The tropical caprellid amphipod Paracaprella pusilla: a new alien crustacean in the Mediterranean Sea

Paracaprella pusilla Mayer (Fauna und Flora des Golfes von Neapel 17:1–55, 1890), originally described from Brazil, is one of the most abundant caprellid amphipod species in tropical and subtropical seas around the world. During a survey of caprellid amphipods from marinas along the Balearic Island (Western Mediterranean Sea) carried out between November 2011 and August 2012, we found two established populations of P. pusilla in Mallorca and Ibiza, respectively. So far, its occurrence in European waters was reported only from southwestern Spain in 2010. This record represents a northward range expansion of the species’ distribution, which is found for the first time in the Mediterranean. This is also the first record of the genus Paracaprella in the Mediterranean Sea. The most probable introduction vector was ship fouling. We also found the invasive caprellid Caprella scaura Templeton (Trans Entomol Soc Lond 1:185–198, 1836) in Mallorca and Menorca, which is recorded for the first time in the Balearic Islands, confirming its rapid expansion along the Mediterranean. When comparing reproductive traits between both alien species, we found that P. pusilla has a higher fecundity than C. scaura for the same female size. Taking into account this evidence, the species may be expected to appear in other Mediterranean and adjacent areas.     

Niche overlap between juvenile flatfishes, Platichthys flesus and Solea solea, in a southern European estuary and adjacent coastal waters

The distribution and abundance patterns as well as the feeding ecology of two flatfishes, Platichthys flesus (Linnaeus, 1758) and Solea solea (Linnaeus, 1758), were studied in the Douro estuary and adjacent coastal waters (Portugal) in order to evaluate the niche overlap between these species. Fish were collected during sampling surveys conducted every 2 months between November 2000 and March 2002 using a 12‐m otter‐trawl with 18 mm stretched mesh size, at 12 sites within the estuary and six sites in the adjacent coastal area. The highest densities of P. flesus were registered in the middle estuary; a peak density of 9.12 ind 1000 m^?2 was obtained in October 2001. Solea solea densities were low compared with P. flesus; the highest values were also recorded in the middle estuary in October 2001. For both species, the proportion of juveniles was above 90% within the estuary. Highest densities of P. flesus and S. solea were recorded at sites with low water depth and high densities of crustaceans and polychaetes, the main food items in the diet of these species. High values of spatial and diet niche overlap were found between these two flatfishes (0.97 and 0.92, respectively).     

Molecular Investigation and Phylogeny of Anaplasma spp. in Mediterranean Ruminants Reveal the Presence of Neutrophil-Tropic Strains Closely Related to A. platys

Few data are available on the prevalence and molecular typing of species belonging to the genus Anaplasma in Mediterranean ruminants. In this study, PCR analysis and sequencing of both 16S rRNA and groEL genes were combined to investigate the presence, prevalence, and molecular traits of Anaplasma spp. in ruminants sampled on the Island of Sardinia, chosen as a subtropical representative area. The results demonstrate a high prevalence of Anaplasma spp. in ruminants, with animals infected by at least four of six Anaplasma species (Anaplasma marginale, A. bovis, A. ovis, and A. phagocytophilum). Moreover, ruminants host a number of neutrophil-tropic strains genetically closely related to the canine pathogen A. platys. The high Anaplasma spp. prevalence and the identification of as-yet-unclassified neutrophil-tropic strains raise concerns about the specificity of serological tests routinely used in ruminants and provide additional background for reconstructing the evolutionary history of species genetically related to A. phagocytophilum.