The first BAFF gene cloned from the cartilaginous fish

B-cell activating factor (BAFF), a member of the TNF family, is critical to the survival, proliferation, maturation, and differentiation of B-cells. In the present study, a CpBAFF was amplified from the white-spotted catshark (Chiloscyllium plagiosum) using RT-PCR and RACE (rapid amplification of cDNA end) techniques. To our knowledge, this is the first report of any BAFF gene being cloned from a cartilaginous fish. The open reading frame (ORF) of CpBAFF cDNA consists of 819 bases encoding a protein of 272 amino acids. This protein was found to contain a predicted transmembrane domain, a putative furin protease cleavage site, and a typical TNF homology domain corresponding to other identified BAFF homologues. Sequence alignment showed that CpBAFF shares 37-57% identity with BAFF amino acid sequences reported in other vertebrates. Three-dimensional structure modeling analysis revealed a soluble mature portion of CpBAFF (CpsBAFF) with a long D-E loop specific to the BAFF gene, which has not been found in other reported TNF proteins. Phylogenetic reconstruction showed that CpBAFF is most closely related to other fish BAFFs and clusters with BAFF genes from higher vertebrates (reptiles, birds, and mammals). Real-time quantitative RT-PCR demonstrated that CpBAFF mRNA expression was high in the spleen but moderate in the kidney and branchia. Recombinant CpsBAFF fused to NusA-His(6)-tag was efficiently expressed in Escherichia coli BL21 (DE3), and a molecular weight of approximately 83 kDa was determined using SDS-PAGE and Western blotting. In vitro MTT assay indicated that the purified pET43.1a (+)-CpsBAFF protein can co-stimulate the proliferation of mammalian B-cells with anti-IgM in a dose-dependent manner. The present findings not only present novel information that may be relevant to shark immunity but also provide some new insights into the origins and evolution of immunity in all vertebrates.     

The fish Perccottus glenii: history of introduction to western regions of Eurasia

The fish,Perccottus glenii, appeared in western regions of Eurasia in 1916 and has several centres of invasion. Ways of distribution are discussed. Uncontrolled distribution of this fish leads to significant negative changing of freshwater ecosystems.     

Dactylogyridean monogeneans of the siluriform fishes of the Old World

This is a catalogue and discussion of the known dactylogyridean monogenean genera of siluriform fishes of the Old World. Of a total of 38 nominal genera, only 19 are considered valid. Seventeen of these 19 genera are currently in the Ancyrocephalidae (containing the Ancyrocephalinae and Ancylodiscoidinae), whilst the other two (Neocalceostoma and Neocalceostomoides) are in the Neocalceostomatidae. The 17 genera are Anchylodiscus, Ancylodiscoides, Bagrobdella, Bifurcohaptor, Bychowskyella, Chauhanellus, Cornudiscoides, Hamatopeduncularia, Mizelleus, Paraquadriacanthus, Pseudancylodiscoides, Protoancylodiscoides, Quadriacanthus, Schilbetrema, Schilbetrematoides, Synodontella and Thaparocleidus. Clariotrema Long, 1981 and Neobychowskyella Ma, Wang & Li, 1983 are considered synonyms of Bychowskyella Akhmerov, 1952, Anacornuatus Dubey, Gupta & Agarwal, 1992 is considered a synonym of Quadriacanthus Paperna, 1961, Mizellebychowskia Gupta & Sachdeva, 1990 is considered a synonym of Neocalceostoma Tripathi, 1959 and Hargitrema Tripathi, 1959 is treated as a synonym of Hamatopeduncularia Yamaguti, 1953. It is proposed that the Ancylodiscoidinae be raised to family status within the order Dactylogyridea to accommodate these 17 `ancyrocephalid' genera from siluriforms, together with Malayanodiscoides and Notopterodiscoides from notopterids. A key and the diagnostic characteristics of the 19 recognised dactylogyridean genera from catfishes plus two from notopterids, together with a list of species and synonyms, are included. New combinations made in this work are Thaparocleidus avicularia (Chen, 1987) n. comb., T. calyciflorus (Chen, 1987) n. comb., T. choanovagina (Luo & Lang, 1981) n. comb., T. dissimilis (Chen, 1988) n. comb., T. leiocassis (Reichenbach-Klinke, 1959) n. comb., T. meticulosa (Chen, 1987) n. comb., T. parasoti (Zhao & Ma, 1999) n. comb., T. persculpus (Chen, 1987) n. comb., T. valga (Chen, 1987) n. comb. and T. wulingensis (Yao & Wang, 1997) n. comb. [all from Silurodiscoides] and Bychowskyella glyptothoraci (Ma, Wang & Li, 1983) n. comb. [from Neobychowskyella].     

Ladislavella tumrokensis: The first molecular evidence of a Nearctic clade of lymnaeid snails inhabiting Eurasia

In this study, we provide the first molecular evidence for a possible connection between freshwater mollusc faunas across the Bering Strait via the Beringian Land Bridge using data inferred from gastropods of the family Lymnaeidae. The gastropods collected from geothermal springs in the Tumrok Mountains, West Kamchatka, Russia, share the nuclear internal transcribed spacer 2 (ITS2) and the cytochrome oxidase subunit I gene (COI) haplotypes, thus being as sister to those recorded for lymnaeid snails in the Stagnicola elodes group from Canada and the USA. Two lymnaeid species, Lymnaea (Orientogalba) tumrokensis Kruglov and Starobogatov, 1985 Kruglov, N. D., & Starobogatov, Y. I. (1985). Ob'yom podroda Galba i skhodnykh s nim podrodov roda Lymnaea [The volume of the subgenus Galba and of the other similar subgenera of the genus Lymnaea (Gastropoda, Pulmonata)]. Zoologicheskiy Zhurnal, 64, 24–35.[Web of Science ®] , [Google Scholar] and Lymnaea (Polyrhytis) kurenkovi Kruglov and Starobogatov, 1989 Kruglov, N. D., & Starobogatov, Y. I. (1989). Mollyuski podroda Polyrhytis roda Lymnaea fauny SSSR (Pulmonata, Lymnaeidae) [Molluscs of the subgenus Polyrhytis of the genus Lymnaea of the fauna of the USSR (Pulmonata, Lymnaeidae)]. Zoologicheskiy Zhurnal, 68, 14–20.[Web of Science ®] , [Google Scholar], were described from the Tumrok geothermal locality, but actually they are morphological variations of a single taxon of subspecies rank re-classified here as Ladislavella catascopium tumrokensis. This subspecies is the first discovered representative in the genus, which formed a dwarf race in a geothermal habitat. Our findings highlight the possible exchange between freshwater faunas in Beringia during the Pleistocene and an important role of geothermal ecosystems as possible cryptic refugia for freshwater hydrobionts.     

Freshwater fish otoliths from the Deccan Trap associated sedimentary (Cretaceous-Tertiary transition) beds of Rangapur,Hyderabad, District,Andhra Pradesh,India

The present paper describes 12 species of fish otoliths recovered by washing and screening processes from the Deccan Trap associated sedimentary (Intertrappean) beds exposed near Rangapur, Hyderabad District, Andhra Pradesh, India. The present collection of otoliths contains four major groups: Clupeomorpha (“Clupeidarum” sp.), Osteoglossomorpha (“Osteoglossidarum” deccanensis sp. nov., “O”. intertrappus sp. nov. and “Notopteridarum” nolfi sp. nov.), Protacanthopterygii (“Salmoniformorum” rectangulus sp. nov.), and Percomorpha (Dapalis sp., “Apigonidarum” ovatus sp. nov., “Serranidarum” sp., “Percoideorum” ellipticus sp. nov., “P.” rangapurensis sp. nov., “Percoideorum” sp. 1 and “Percoideorum” sp. 2). This collection of otoliths represents freshwater lacustrine deposition of the sediments. The age of the Intertrappean beds is considered Uppermost Cretaceous to Palaeoncene on the basis of freshwater ostracode (Paracypretta jonesi, Mongolianella hislopi and Candoniella sp.) and charophyte (Platychara perlata and Nemegtichara sp.) assemblages.     

The theriofaunistic zoning of northern Eurasia

For the purpose of zoning on the basis of theriofauna, Northern Eurasia was considered within the boundaries of the Soviet Union in 1991 and was divided into 245 mapping units. Mapping units were marked on the World Vegetation Map at a scale of 1: 2000000. Each mapping unit occupied a territory within the limits of a natural subzone with a latitudinal distance of 10°. A list of mammal species was generated for each unit. Jaccard similarity coefficients were calculated for these lists; the coefficients were used as the basis for performing cluster analysis of theriofauna of the mapping units. The results of calculations were used to create a hierarchical classification, which includes three theriofauna regions divided into seven subregions. They were classified as island or mainland. All the subregions (except one) were delimited into 18 provinces and 17 districts; one of the districts was delimited into four subdistricts. Environmental factors that correlate with heterogeneity of theriofauna within the studied territory were described. The proposed zoning is 1.9–3 times more informative than previously developed schemes and takes into account 69% of the variance of the similarity coefficients of the faunas of specific regions (coefficient of multiple correlation is 0.83). The association with environmental factors and natural conditions may explain 83% of the heterogeneity of the theriofauna (correlation coefficient is 0.91). Comparing the results of zoning that were carried out for different classes of terrestrial vertebrates, we found significant similarity between causes of fauna heterogeneity (zonal features, remoteness, sun exposure, and their combined effect). In addition, the differences in tolerance to the environment among the studied animal classes resulted in substantial discordance of the boundaries of the described taxa and their hierarchy. This discordance was found during zoning. Because of this, general conclusions concerning the heterogeneity of the fauna of terrestrial vertebrates can be made only after the total analysis of their fauna is completed.     

The boreal forests of north-eastern Eurasia

The distribution, diversity and structure of boreal forests of monsoon Asia are reviewed. The boreal zone is circumscribed by the isotherms of 15°C and 45°C of Kira's Warmth Index (WI) and includes the territory of the Amur basin, the seashores of the Sea of Okhotsk, Kamchatka, Sakhalin and the Kuril islands. Boreal forests also occur on the mountains of Hokkaido, Honshu, Korea and NE China. The oceanic sectors of the boreal zone are composed mainly of birch forests, the marine sectors of spruce-fir forests and the continental sectors of larch and pine forests. The upper limit of the boreal forests ascends from the lowest level in the North to ca. 1500 m a.s.l. in the South of the zone, and reaches above 2500 m in the mountains of the temperate zone. In the boreal zone the secondary forests are common. They form after fires and cutting. Volcanism is an essential factor in the forest dynamics in the oceanic part of the region. It is suggested that as a result of global warming one may expect a strong alteration in vegetation pattern, especially in the northern and mountain areas.Paper presented at the International Symposium on Global Change Impacts on Terrestrial Ecosystems in Monsoon Asia (TEMA) Waseda University, Tokyo, 4–6 September 1993.     

Compaction rate of in vitro fertilized bovine embryos related to the interval from insemination to first cleavage

A study was conduced on early cleavage divisions and timing of compaction in bovine preimplantation-stage embryos. Zygotes were produced using conventional in vitro maturation and fertilization procedures. Twenty hours post insemination, the zygotes were denuded and cultured with oviduct epithelial cells in B2 medium + 10% estrous cow serum. Starting at 24 hours post insemination, the embryos (n=657) were evaluated every 6 hours and then were put into different co-culture drops according to their cell number. Starting from 78 hours post insemination, the cleavage rate was evaluated every 12 hours. Embryos were stained with Hoechst 33342 at the compacted morula stage or when they were degenerated, at 162 hours post insemination. Developmentally capable embryos were characterized by a rapid cleavage rate in the first 3 cell cycles and by an extended 8- to 16-cell stage. Peak concentrations of 2-, 4-, 8- and 16-cell stages emerged at 36, 42, 60 and 102 hours post insemination, respectively. Compaction did not occur until 126 hours post insemination. The rate of compaction was significantly higher in embryos that were at the 2-cell stage before or at 36 hours post insemination (P < 0.05). The mean cell numbers of compacted morulae that were identified at 126 and 138 hours post insemination were 30.9 +/- 6.8 and 31.6 +/- 7.7, respectively. These results indicate that developmentally capable bovine embryos reach the 2-cell stage at 36 hours post insemination, and that they become compacted at the 32-cell stage, which usually occurs between 126 and 138 hours post insemination.     

A first case of myiasis in fish

Maggots of an unidentified species of Caliphora were discovered in freshwater fish, Astyanax mexicanus fasciatus, shipped from Hong Kong to Norway. This represents the first reported case of myiasis in fish.     

Validity of the agonid fish,Podothecus hamlini,and the first confirmed record from Japanese waters

An erratum to this article is available at .     

The development of the nervous system: from fly to fish,from fish to man....

The nervous system of vertebrates is more complex and less tractable than that of current model organisms such as the fly and the nematode. Here we present a vertebrate sensory system which is structurally simple, experimentally accessible and genetically suitable: the lateral line of the zebra-fish. We review our recent work on the development of this system, with a particular emphasis on the migration events that shape the pattern of sense organs. Some of the factors involved in these migration events turn out to be similar to the factors that direct the formation of metastases in specific types of human cancers, illustrating once again the remarkable conservation of developmental mechanisms and genes throughout the animal kingdom.     

Hyperparasitism by helminths: new records of cestodes and nematodes in proteocephalid cestodes from South American siluriform fishes

Proteocephalid cestode hyperparasites are reported from numerous proteocephalids occurring in pimelodid fishes in different regions of Brazil. In addition, three specimens of a nematode hyperparasite are reported from the proteocephalid cestode Choanoscolex abscissus from the pimelodid fish Pseudoplatystoma corruscans in Brazil. Previous records of cestode and nematode hyperparasites of cestodes are listed, and the possible identities of the Brazilian records are discussed.     

The Genetic Legacy of the Expansion of Turkic-Speaking Nomads across Eurasia

The Turkic peoples represent a diverse collection of ethnic groups defined by the Turkic languages. These groups have dispersed across a vast area, including Siberia, Northwest China, Central Asia, East Europe, the Caucasus, Anatolia, the Middle East, and Afghanistan. The origin and early dispersal history of the Turkic peoples is disputed, with candidates for their ancient homeland ranging from the Transcaspian steppe to Manchuria in Northeast Asia. Previous genetic studies have not identified a clear-cut unifying genetic signal for the Turkic peoples, which lends support for language replacement rather than demic diffusion as the model for the Turkic language’s expansion. We addressed the genetic origin of 373 individuals from 22 Turkic-speaking populations, representing their current geographic range, by analyzing genome-wide high-density genotype data. In agreement with the elite dominance model of language expansion most of the Turkic peoples studied genetically resemble their geographic neighbors. However, western Turkic peoples sampled across West Eurasia shared an excess of long chromosomal tracts that are identical by descent (IBD) with populations from present-day South Siberia and Mongolia (SSM), an area where historians center a series of early Turkic and non-Turkic steppe polities. While SSM matching IBD tracts (> 1cM) are also observed in non-Turkic populations, Turkic peoples demonstrate a higher percentage of such tracts (p-values ≤ 0.01) compared to their non-Turkic neighbors. Finally, we used the ALDER method and inferred admixture dates (~9th–17th centuries) that overlap with the Turkic migrations of the 5th–16th centuries. Thus, our results indicate historical admixture among Turkic peoples, and the recent shared ancestry with modern populations in SSM supports one of the hypothesized homelands for their nomadic Turkic and related Mongolic ancestors.     

Phylogeography of the mallard Anas platyrhynchos from Eurasia inferred from sequencing of the mtDNA control region

Phylogenetic relationships, demographic history, and geographic distribution of the mtDNA haplotypes of the mallard Anas platyrhynchos were examined in three populations, Indian, Northern European, and Far Eastern. Two divergent halotype groups, A and B, were found in the Far Eastern population, while haplotypes identified in Northern European and Far Eastern populations were exclusively of the A group. The presence of B group haplotypes in the Far Eastern population can be explained either in terms of hybridization of the mallard with spot-billed duck Anas zonorhyncha at the south of the Russian Far East, or by the mtDNA paraphyly in mallards. In general, mallards from Eurasia were characterized by low genetic population differentiation along with slightly expressed phylogeographic structure. The most differentiated was the population from India (??_st = 0.076?0.077), while the difference between Northern European and Far Eastern populations was extremely low (??_st = 0.0029). Differentiation of Anas platyrhynchos Indian population was determined by the fact that a part of the population, inhabiting southern and eastern coasts of the Hindustan Peninsula, was resident.     

The first completed genome sequence from a teleost fish (Fugu rubripes) adds significant diversity to the nuclear receptor superfamily

Defining complete sets of gene family members from diverse species provides the foundation for comparative studies. Using a bioinformatic approach, we have defined the entire nuclear receptor complement within the first available complete sequence of a non-human vertebrate (the teleost fish Fugu rubripes). In contrast to the human set (48 total nuclear receptors), we found 68 nuclear receptors in the Fugu genome. All 68 Fugu receptors had a clear human homolog, thus defining no new nuclear receptor subgroups. A reciprocal analysis showed that each human receptor had one or more Fugu orthologs, excepting CAR (NR1I3) and LXRβ (NR1H2). These 68 receptors add striking diversity to the known nuclear receptor superfamily and provide important comparators to human nuclear receptors. We have compared several pharmacologically relevant human nuclear receptors (FXR, LXRα/β, CAR, PXR, VDR and PPARα/γ/δ) to their Fugu orthologs. This comparison included expression analysis across five Fugu tissue types. All of the Fugu receptors that were analyzed by PCR in this study were expressed, indicating that the majority of the additional Fugu receptors are likely to be functional.     

The first reliable record of fossil leatherback sea turtle (Dermochelyidae) in northern Eurasia (Middle Eocene of Ukraine)

Plates of the epithecal bony shell of turtles of the family Dermochelyidae from the Middle Eocene (Lutetian) of the Ak-Kaya locality (Crimea, Ukraine) are described. This material, determined as Dermochelyidae indet., is the first reliable record of fossil dermochelyids in northern Eurasia.     

Plectorhinchus mediterraneus from off north east Italy and Slovenia–the first records of fish of the family Haemulidae from the Adriatic Sea

The haemulid Plectorhinchus mediterraneus , previously unrecorded in the Adriatic Sea, has been found recently in the Gulf of Trieste, in Diga Rizzo, Italy, and near Piran, Slovenia.