Ecologal and parasitological chracteristics of redfish <Emphasis Type="Italic">Sebastes mentella</Emphasis> (Scorpaeniformes: Sebastidae) from the Norwegian Sea and adjacent waters

Special traits of ecology, zoogeography, formation of fauna of parasites, and occurrence of external lesions are investigated in redfish Sebastes mentella from the Norwegian Sea and the adjacent area of the Barents Sea. A considerable weakening of connection with bottom biocenoses in redfish in the pelagial of the Norwegian Sea indicates that it lives here for most of its annual life cycle. In redfish from south of the open part of the Norwegian Sea, there are noticeable differences in the fauna of parasites and in occurrence of external lesions from those in the fish from the north and east of this sea while traits characteristic of redfish from the Irminger Sea are present.     

Taxonomic review of the <Emphasis Type="Italic">Sebastes inermis</Emphasis> species complex (Scorpaeniformes: Scorpaenidae)

A taxonomic review of three color morphotypes of the Sebastes inermis species complex established the existence of three valid species, viz. S. inermis, S. ventricosus, and S. cheni. The complex is defined by having two sharp lachrymal spines, the head weakly armed with nasal, preocular, supraocular and parietal spines, and the caudal fin not distinctly emarginated. Sebastes inermis, known from southern Hokkaido southward to Kyushu, Japan, and the southern part of the Korean Peninsula, is characterized as follows: body dark red or light brown dorsally and laterally when fresh, pectoral fin extending beyond level of anus when depressed, pectoral-fin rays 15, anal-fin rays 7, pored lateral line scales 36–44 and gill rakers 31–37. Sebastes ventricosus, known from Iwate and Ishikawa Prefecture southward to Kyushu, Japan, and the southern part of the Korean Peninsula, is characterized as follows: body somewhat greenish-black dorsally and dark silver ventrally when fresh, pectoral-fin rays 16, anal-fin rays 7–8, pored lateral line scales 43–49, and gill rakers 35–39. Sebastes cheni, known from Iwate and Akita Pref. southward to Kyushu, Japan, and the southern part of the Korean Peninsula, is characterized as follows: body dark golden-brown dorsally and laterally when fresh, pelvic fin extending beyond anus when depressed, pectoral-fin rays 17, anal-fin rays 8, pored lateral line scales 37–46 and gill rakers 32–37. In the genetic analysis, the presence or absence of two AFLP fragments was completely fixed among the three species. Sebastes tokionis and S. guentheri are regarded as junior synonyms of S. inermis and S. ventricosus, respectively. A lectotype is designated for S. cheni, and a key to the three species of the S. inermis species complex provided.     

Sexual dimorphism in <Emphasis Type="Italic">Sebastes owstoni</Emphasis> (Scorpaenidae) from the Sea of Japan

Morphological and genetic differences between red and yellow morphotypes of Sebastes owstoni were investigated, utilizing 277 males [84.0–194.3 mm in standard length (SL)] and 542 females (92.3–251.5 mm SL) from the Sea of Japan. All males smaller than 120 mm SL were characterized by red body color. The frequency of specimens with yellow body color thereafter increased gradually with SL, all specimens larger than 170 mm SL being yellow. The specimens with yellow body color were observed throughout the year. All females smaller than 170 mm SL were characterized by red body color, the frequency of specimens with yellow body color tending to slightly increase with SL. However, most females had red body color, except for 16 specimens (177.7–241.5 mm SL) that were yellow, growth-related color change from red to yellow being uncommon. Morphological analysis of 49 males (107.6–193.3 mm SL) and 68 females (108.7–241.5 mm SL) showed the head length, orbit diameter, lower jaw length, and predorsal length to be relatively greater, but the distance between the pelvic and anal fins less, in males. A discriminant analysis using Mahalanobis distances resulted in 100% correct assignment of specimens to sex, regardless of SL and body color. In addition, no genetic differences were apparent between red and yellow individuals in mitochondrial DNA sequence analyses from the threonine tRNA to the first half of the control region (498 bp). Accordingly, the differences in body color, maximum size, and the five morphometric characters listed above were considered to represent sexual dimorphism. That evidenced by body color was considered to appear after that shown by morphometric characters, some exceptions in the former occurring in females. This is the first report of permanent sexual dimorphism in body color in Sebastes.     

Structure and specific features of formation of aggregations of deepwater redfish <Emphasis Type="Italic">Sebastes mentella</Emphasis> (Scorpaenidae) in the Norwegian Sea pelagial

Results of studies of the structure and specific features of formation of aggregations of deepwater redfish Sebastes mentella in the Norwegian Sea pelagial are provided. Data on the biological characteristics of S. mentella from different regions of the Norwegian Sea pelagial do not allow us to consider its aggregations as separate populations. On the basis of comparative analysis of the structure of aggregations in the Norwegian Sea and of population parameters and specific features of the life cycle of S. mentella in different parts of the Atlantic Ocean, its complex intraspecies organization at sites of overlapping of two largest populations—North Atlantic and Norwegian-Barents Sea-was established. The formation of pelagic aggregations in the water area of the Norwegian Sea occurs due to migration of maturing and mature individuals from the adjoining water areas. In the southern areas of the Norwegian Sea, dominant recruitment comes from the pelagial of the northeastern part of the Irminger Sea, which is promoted by the direction of streams of the North-Atlantic Current; it is not excluded either that fish can migrate to the southern part of the sea from the slopes of the Faeroes, Faeroes-Icelandic threshold, and the western coast of Norway. Migration to the northern areas of the sea is mainly performed by rapidly maturing fish from the rearing region from the western slopes of the Barents Sea and Spitsbergen Archipelago. The presence of seasonal migrations hinders the formation in the pelagial of perch isolated groups and promotes their migration.     

Biological and ecological characteristics of deepwater redfish <Emphasis Type="Italic">Sebastes mentella</Emphasis> (Scorpaenidae) at different depths in the pelagial of the Irminger Sea

Results of comparative analysis of several ecological and biological indices of Sebastes mentella from the northern Atlantic (the Irminger Sea, Reykjanes Ridge) inhabiting different depths, 0–500 and 501–1000 m, are provided. A considerable similarity in the rates of linear and weight growth, sexual maturation, composition of parasitofauna, the degree of invasion by parasites of most species, specific features of invasion by copepod Sphyrion lumpi, as well as the pattern of pigment formations on the skin of S. mentella from two studied layers, testify to the absence of isolated groups of this species in the pelagial of the Irminger Sea. It was established that the formation of perch aggregations at a depth larger than 500 m takes place due to a partial redistribution from the upper layer of individuals aged 5 to 18 years and a complete departure to large depths of perch individuals older than 18 years. A conclusion was made that it is incorrect to use as a criterion for the intraspecies differentiation of the perch the insignificant differences in the occurrence of pigment formations on the skin that are the result of age changes in fish and an obvious pathology of this phenomenon. A decrease in the occurrence of melanin inclusions in the muscular tissue of fish at a depth larger than 500 m is also related to age changes and the change in the diet of the perch. Vertical variation, in particular biological parameters in pelagic aggregations, was determined by specific features of biology, ecology, and the life cycle of the species. In establishing measures of control of the international fishery in the pelagial of the Irminger Sea, it is necessary to proceed from the unity of aggregations of S. mentella throughout the vertical of their distribution.     

Intraspecies structure of beaked redfish <Emphasis Type="Italic">Sebastes mentella</Emphasis> of the Atlantic and Arctic oceans

On the basis of the results of complex interdisciplinary investigations of the population composition and structure of the beaked redfish Sebastes mentella of the Atlantic and Arctic oceans, its three populations are discerned relatively isolated from each other by the system of permanent marine currents—North Atlantic, Flemish-Cape, and Norway-Barents Sea. The population structure of the species in the southern part of its area corresponds to the model of a local stock. Interaction of the North Atlantic and the Norway-Barents Sea populations well correspond to the model of fluctuating stocks. Redfish aggregations in different biotopes (mesobenthal and mesopelagial) are intrapopulational epigenetic groups. In the period of warm and anomalously warm years, a part of mature specimens from the pelagial of the North Irminger Sea make an irreversible migration to the southern part of the Norwegian Sea and form there mixed aggregations of fish from the North Atlantic and Norway-Barents Sea populations. With consideration of the effect of climatic–oceanological processes, a principally new scheme is elaborated describing the process of seasonal migrations of redfish in the mesobenthal and mesopelagial. The previous views on direction of return migrations of redfish of the Norway-Barents Sea population are reconsidered. Juveniles from the western part of the Barents Sea and Spitsbergen not only supplement the demersal aggregations but also migrate to the pelagial of the Norwegian Sea.     

Biological and genetic characteristics of deepwater redfish <Emphasis Type="Italic">Sebastes mentella</Emphasis> (Scorpaenidae) from the open part of the Norwegian Sea

The analysis is conducted of the biological and genetic characteristics of deepwater redfish Sebastes mentella from the open part of the Norwegian Sea. A similarity of the studied sample with analogous groups of deepwater redfish from the Northeast Atlantic in biological parameters and their dynamics is revealed. Polymorphism is registered in three of the nine studied enzyme loci: malic enzyme (NADF-dependent malatedehydrogenase), MEP-1*; phosphoglucomutase from the liver, PGM-2*; and glucose-6-phosphateisomerase, PGI*. A pairwise comparison of allele frequencies shows a similarity of the samples of deepwater redfish from the enclave of the Norwegian Sea. In addition, based on a pairwise analysis, significant differences are absent between the samples with similar biological characteristics from the open part of the Norwegian Sea and the Irminger Sea.     

New combinations and typifications in <Emphasis Type="Italic">Bistorta</Emphasis>, <Emphasis Type="Italic">Persicaria</Emphasis>, <Emphasis Type="Italic">Polygonum,</Emphasis> and <Emphasis Type="Italic">Rumex</Emphasis> (Polygonaceae)

New combinations are proposed in anticipation of the Polygonaceae treatment in the forthcoming volume of Intermountain Flora: Polygonum kelloggii var. esotericum, P. kelloggii var. watsonii , Rumex densiflorus var. pycnanthus , R. salicifolius var. utahensis, and R. occidentalis var. tomentellus. Typifications are proposed to facilitate ongoing studies in Polygonaceae and to maintain current usage.     

<Emphasis Type="Italic">Gyrodactylus salaris</Emphasis> (Monogenea,Gyrodactylidae) infections on resident Arctic charr (<Emphasis Type="Italic">Salvelinus alpinus</Emphasis>) in southern Norway

This study surveys the distribution of Gyrodactylus salaris on resident Arctic charr, Salvelinus alpinus, in lakes connected to three south-Norwegian watercourses: Numedalsvassdraget, Skiensvassdraget and Hallingdalsvassdraget. Gyrodactylus salaris infected charr was only recorded in Numedalsvassdraget. The parasites had the same mitochondrial haplotype as those previously reported on charr in Lake Pålsbufjorden, which is part of Numedalsvassdraget. Since the G. salaris-charr association is persistent in Pålsbufjorden and has a wide distribution above the stretches of the watercourse inhabited by anadromous salmonids, this is considered a stable, although perhaps relatively young, host-parasite system. More detailed analyses of these interactions revealed seasonal variations in the parasite population dynamics between late summer and late autumn, with heavier infections occurring in males and older fish in October. This is explained by the combined action of seasonal differences in temperature and physiology and ecology of host cohorts. It is assumed that the occurrence of G. salaris on charr in Pålsbufjorden resulted from a host switch to charr from rainbow trout, Onchorynchus mykiss. Host switches may cause significant expansions of the geographical range of pathogenic variants of G. salaris. Therefore, observations of frequently occurring G. salaris on charr have implications for the diagnosis, management and control of salmonid gyrodactylosis.     

The tyrosine <Emphasis Type="Italic">O</Emphasis>-prenyltransferase SirD catalyzes <Emphasis Type="Italic">O</Emphasis>-, <Emphasis Type="Italic">N</Emphasis>-, and <Emphasis Type="Italic">C</Emphasis>-prenylations

Recently, the prenyltransferase SirD was found to be responsible for the O-prenylation of tyrosine in the biosynthesis of sirodesmin PL in Leptosphaeria maculans. In this study, the behavior of SirD towards phenylalanine/tyrosine and tryptophan derivatives was investigated. Product formation has been observed with 12 of 19 phenylalanine/tyrosine derivatives. It was shown that the alanine structure attached to the benzene ring and an electron donor, e.g., OH or NH₂, at its para-position are essential for the enzyme activity. Modifications were possible both at the side chain and the benzene ring. Enzyme products from seven phenylalanine/tyrosine derivatives were isolated and characterized by MS and NMR analyses including HSQC and HMBC and proven to be O- or N-prenylated derivatives at position C4 of the benzene rings. K _M values of six selected derivatives were found in the range of 0.10–0.68 mM. Catalytic efficiencies (K _cat/K _M ) were determined in the range of 430–1,110 s⁻¹·M⁻¹ with l-tyrosine as the best substrate. In addition, 7 of 14 tested tryptophan analogs were also accepted by SirD and converted to C7-prenylated derivatives, which was confirmed by comparison with products obtained from enzyme assays using a 7-dimethylallyltryptophan synthase 7-DMATS from Aspergillus fumigatus.     

The <Emphasis Type="Italic">Caenorhabditis</Emphasis><Emphasis Type="Italic">briggsae</Emphasis> genome contains active <Emphasis Type="Italic">CbmaT1</Emphasis> and <Emphasis Type="Italic">Tcb1</Emphasis> transposons

The maT clade of transposons is a group of transposable elements intermediate in sequence and predicted protein structure to mariner and Tc transposons, with a distribution thus far limited to a few invertebrate species. We present evidence, based on searches of publicly available databases, that the nematode Caenorhabditis briggsae has several maT-like transposons, which we have designated as CbmaT elements, dispersed throughout its genome. We also describe two additional transposon sequences that probably share their evolutionary history with the CbmaT transposons. One resembles a fold back variant of a CbmaT element, with long (380-bp) inverted terminal repeats (ITRs) that show a high degree (71%) of identity to CbmaT1. The other, which shares only the 26-bp ITR sequences with one of the CbmaT variants, is present in eight nearly identical copies, but does not have a transposase gene and may therefore be cross mobilised by a CbmaT transposase. Using PCR-based mobility assays, we show that CbmaT1 transposons are capable of excising from the C. briggsae genome. CbmaT1 excised approximately 500 times less frequently than Tcb1 in the reference strain AF16, but both CbmaT1 and Tcb1 excised at extremely high frequencies in the HK105 strain. The HK105 strain also exhibited a high frequency of spontaneous induction of unc-22 mutants, suggesting that it may be a mutator strain of C. briggsae.     

Prevalence,intensity and associated factor analysis of <Emphasis Type="Italic">Tropilaelaps</Emphasis><Emphasis Type="Italic">mercedesae</Emphasis> infesting <Emphasis Type="Italic">Apis</Emphasis><Emphasis Type="Italic">mellifera</Emphasis> in China

Tropilaelaps mercedesae is a serious ectoparasite of Apis mellifera in China. The aim of this study was to investigate the infestation rates and intensity of T. mercedesae in A. mellifera in China, and to explore the relative importance of climate, district, management practices and beekeeper characteristics that are assumed to be associated with the intensity of T. mercedesae. Of the 410 participating apiaries, 379 apiaries were included in analyses of seasonal infestation rates and 352 apiaries were included in multivariable regression analysis. The highest infestation rate (86.3%) of T. mercedesae was encountered in autumn, followed by summer (66.5%), spring (17.2%) and winter (14.8%). In autumn, 28.9% (93) of the infested apiaries were in the north (including the northeast and northwest of China), 71.1% (229) were in the central and south (including east, southeast and southwest China), and 306 apiaries (82.9%) were co-infested by both T. mercedesae and Varroa. Multivariable regression analysis showed that geographical location, season, royal jelly collection and Varroa infestation were the factors that influence the intensity of T. mercedesae. The influence of beekeeper’s education, time of beekeeping, operation size, and hive migration on the intensity of T. mercedesa was not statistically significant. This study provided information about the establishment of the linkage of the environment and the parasite and could lead to better timing and methods of control.     

<Emphasis Type="Italic">Careproctus kidoi</Emphasis>, a new Arctic species of snailfish (Teleostei: Liparidae) from Baffin Bay

Careproctus kidoi sp. nov. is described from the Baffin Bay between Greenland and Canada, in the northern most part of the western North Atlantic. During a series of bottom trawl surveys conducted in 1988–2004, 22 specimens of an undescribed species of Careproctus were caught at depths between 952 and 1,487 m. It differs from Arctic and North Atlantic congeners in the combination of the characters: pectoral fin rays 21–26, dorsal fin rays 54–60, anal fin rays 50–54, vertebrae 61–64; sucking disc oval, 4.2–6.6% SL; teeth simple; pyloric coeca 3–12; head pore formula (2-6-7-1); color light to dark brown, stomach dusky to dark brown, peritoneum black. It is generally found in deeper waters than the sympatric C. reinhardti.     

The Mating System of <Emphasis Type="Italic">Amegilla</Emphasis> (<Emphasis Type="Italic">Asarapoda</Emphasis>) <Emphasis Type="Italic">paracalva</Emphasis> Brooks (Hymenoptera: Apidae)

Males of the solitary bee Amegilla (Asarapoda) paracalva employ two mate-locating tactics: aggressive defense of sites from which virgin females are emerging and patrolling flower patches that are visited by conspecific females. At one study site, a single male was able to control an entire emergence area for one or more days. Multiple males patrolled one flower patch, interacting aggressively on occasion but no one individual was able to monopolize this resource. Territorial males at the emergence site secured mates by waiting by tunnels for receptive virgin females to emerge after metamorphosis. Males patrolling the flower patch pounced upon flower visiting conspecifics and mated with receptive females there. Territorial males at the emergence site were larger than average individuals, probably because of the advantage larger males have when grappling with opponents. Flower patrolling males were smaller than territorial males at the emergence sites, perhaps because of the advantages gained by these males from rapid, agile flight.     

<Emphasis Type="Italic">Funastrum rupicola</Emphasis> (<Emphasis Type="Italic">Apocynaceae:</Emphasis><Emphasis Type="Italic">Asclepiadoideae</Emphasis>), a new species from Bolivia

Summary   Funastrum rupicola Goyder, a new species of Apocynaceae: Asclepiadoideae from Bolivia, is described and illustrated. The conservation status of this species is assessed.     

Features of the reproductive cycle in females of the beaked redfish <Emphasis Type="Italic">Sebastes mentella</Emphasis> (Sebastidae)

The reproductive status of some categories of females of the beaked redfish Sebastes mentella has been determined as a result of the histological analysis. The histological characteristic of gonads of large nonreproductive females of redfish is presented for the first time. Gonads of mature females that skip spawning are studied. The cytomorphological characteristic of ovaries after larvae extrusion is specified. A broadened maturity scale for gonads of females of S. mentella supplemented with stages that characterize fish that skip spawning and large nonreproductive females is proposed.     

Actinomycetemcomitin: a new bacteriocin produced by <Emphasis Type="Italic">Aggregatibacter</Emphasis> (<Emphasis Type="Italic">Actinobacillus</Emphasis>) <Emphasis Type="Italic">actinomycetemcomitans</Emphasis>

Aggregatibacter (Actinobacillus) actinomycetemcomitans P_7–20 strain isolated from a periodontally diseased patient has produced a bacteriocin (named as actinomycetemcomitin) that is active against Peptostreptococcus anaerobius ATCC 27337. Actinomycetemcomitin was produced during exponential and stationary growth phases, and its amount decreased until it disappeared during the decline growth phase. It was purified by ammonium sulphate precipitation (30–60% saturation), and further by FPLC (mono-Q ionic exchange and Phenyl Superose hydrophobic interaction) and HPLC (C-18 reversed-phase). This bacteriocin loses its activity after incubation at a pH below 7.0 or above 8.0, following heating for 30 min at 45°C, and after treatment with proteolytic enzymes such as trypsin, α-chymotrypsin, and papain. Actinomycetemcomitin has a molecular mass of 20.3 KDa and it represents a new bacteriocin from A. actinomycetemcomitans.     

Multiple paternity in <Emphasis Type="Italic">Rhipicephalus</Emphasis> (<Emphasis Type="Italic">Boophilus</Emphasis>) <Emphasis Type="Italic">microplus</Emphasis> confirmed by microsatellite analysis

The aim of this study was to determine if individual ticks among the progeny of a single female Rhipicephalus (Boophilus) microplus tick removed from cattle under natural conditions are the result of mating with one or several males. To this end, simulations were run using an existing dataset of genotypes from 8 microsatellite loci to predict the number of samples required and the best locus. Subsequently, 14–22 progeny from each of 15 engorged female ticks removed from three cows, and the engorged females themselves, were genotyped for the BmM1 locus and the minimum number of potential male parents was determined for each progeny group. Of the 15 progeny groups, 10 must have been sired by more than one male, as indicated by the presence of five unique alleles among the progeny or three unique alleles that could not have been contributed by the female. This finding demonstrates multiple paternity in R. microplus.     

Evaluation of the toxicity of <Emphasis Type="Italic">Arthrospira</Emphasis> (<Emphasis Type="Italic">Spirulina</Emphasis>) <Emphasis Type="Italic">platensis</Emphasis> extract

In this study, the methanol extract of Arthrospira (Spirulina) platensis was examined for acute and subchronic toxicities. The extract did not produce any sign of toxicity within 7 days after feeding it at a single high dose of 6 g kg⁻¹ body weight to female and male Swiss mice. For the subchronic toxicity test, the extract at doses of 6, 12, and 24 mg kg⁻¹ body weight was orally administered to six male and six female Wistar rats daily for 12 weeks. Throughout the study period, we did not observe any abnormalities on behavior, food and water intakes, and health status among the treated animals. The hematology and clinical chemistry parameters of treated groups did not significantly differ from those of the controls in both sexes. Postmortem examination of the test groups also showed no abnormalities in both gross and histological findings. These results thus suggest that the methanol extract of A. platensis did not cause acute or subchronic toxicity in our experimental animals.