Teleostei
Dotaz
Zobrazit nápovědu
- MeSH
- glykogen metabolismus MeSH
- mozek anatomie a histologie metabolismus MeSH
- ryby fyziologie MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
The Lower Congo Basin is characterized by a mangrove-lined estuary at its mouth and, further upstream, by many hydrogeographical barriers such as rapids and narrow gorges. Five localities in the mangroves and four from (upstream) left bank tributaries or pools were sampled. On the gills of Coptodon tholloni, Coptodon rendalli, Hemichromis elongatus, Hemichromis stellifer and Tylochromis praecox, 17 species of parasites (Dactylogyridae & Gyrodactylidae, Monogenea) were found, eight of which are new to science. Six of these are herein described: Cichlidogyrus bixlerzavalai n. sp. and Cichlidogyrus omari n. sp. from T. praecox, Cichlidogyrus calycinus n. sp. and Cichlidogyrus polyenso n. sp. from H. elongatus, Cichlidogyrus kmentovae n. sp. from H. stellifer and Onchobdella ximenae n. sp. from both species of Hemichromis. On Cichlidogyrus reversati a ridge on the accessory piece was discovered that connects to the basal bulb of the penis. We report a putative spillback effect of the native parasites Cichlidogyrus berradae, Cichlidogyrus cubitus and Cichlidogyrus flexicolpos from C. tholloni to the introduced C. rendalli. From our results, we note that the parasite fauna of Lower Congo has a higher affinity with the fauna of West African and nearby freshwater ecoregions than it has with fauna of other regions of the Congo Basin and Central Africa.
- MeSH
- biodiverzita MeSH
- cichlidy anatomie a histologie parazitologie MeSH
- fylogeneze MeSH
- fylogeografie MeSH
- infekce červy třídy Trematoda epidemiologie parazitologie veterinární MeSH
- nemoci ryb epidemiologie parazitologie MeSH
- ploštěnci klasifikace genetika izolace a purifikace MeSH
- sladká voda parazitologie MeSH
- žábry parazitologie MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Kongo MeSH
Olfaction plays an important role in a fish's life. Its value may differ at different developmental stages, depending on the feeding style of the species. The goal of the present study was to investigate the olfactory organ of a species that feeds mainly on algae- the bushymouth catfish, Ancistrus dolichopterus-at developmental stages from olfactory placode to the definitive olfactory chamber. For this study, we used light and electron (scanning) microscopy. The topography of the olfactory placode of A. dolichopterus is typical for teleostei. Formation of olfactory pit takes place at the same time as rostral elevation formation. Rostral elevation participates in the formation of the nasal bridge and anterior tubular nostril. It was found out that the anlage of olfactory rosette in A. dolichopterus arises earlier than in most teleostei. However, the number of lamellae does not increase until switching to exogenous feeding. We suppose that the early development of olfactory organ is necessary for intraspecific communication, not just for finding food.
A survey of the gill parasites of Epinephelus costae (Teleostei: Serranidae) was conducted between 2001 and 2005 in the Gulf of Gabès (Tunisia). Five new species of Diplectanidae (Monogenea) were collected, all belonging to Pseudorhabdosynochus Yamaguti, 1958: P. bouaini sp. n., P. dolicocolpos sp. n., P. enitsuji sp. n., P. sinediscus sp. n., and P. sosia sp. n. These five species differ from each other and from all described species of Pseudorhabdosynochus by the morphology and size of their sclerotized vagina. These diplectanids (except P. sinediscus) were also collected from the same host off Dakar in 1981 and 1989. The present paper includes the descriptions and taxonomic considerations of each of these species in addition to an amended diagnosis of Pseudorhabdosynochus. A key to the five new species parasitizing E. costae is provided. These five species are the first diplectanids described from E. costae.
- MeSH
- infekce červy třídy Trematoda parazitologie veterinární MeSH
- nemoci ryb parazitologie MeSH
- Percoidea parazitologie MeSH
- Trematoda anatomie a histologie klasifikace izolace a purifikace MeSH
- žábry parazitologie MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Tunisko MeSH
Rainbowfishes (Melanotaeniidae) are the largest monophyletic group of freshwater fishes occurring in Australia and New Guinea, with 112 species currently recognised. Despite their high taxonomic diversity, rainbowfishes remain poorly studied from a cytogenetic perspective. Using conventional (Giemsa staining, C banding, chromomycin A3 staining) and molecular (fluorescence in situ hybridisation with ribosomal DNA (rDNA) and telomeric probes) cytogenetic protocols, karyotypes and associated chromosomal characteristics of five species were examined. We covered all major lineages of this group, namely, Running River rainbowfish Melanotaenia sp., red rainbowfish Glossolepisincisus, threadfin rainbowfish Iriatherina werneri, ornate rainbowfish Rhadinocentrus ornatus, and Cairns rainbowfish Cairnsichthys rhombosomoides. All species had conserved diploid chromosome numbers 2n = 48, but karyotypes differed among species; while Melanotaenia sp., G. incisus, and I. werneri possessed karyotypes composed of exclusively subtelo/acrocentric chromosomes, the karyotype of R. ornatus displayed six pairs of submetacentric and 18 pairs of subtelo/acrocentric chromosomes, while C. rhombosomoides possessed a karyotype composed of four pairs of submetacentric and 20 pairs of subtelo/acrocentric chromosomes. No heteromorphic sex chromosomes were detected using conventional cytogenetic techniques. Our data indicate a conserved 2n in Melanotaeniidae, but morphologically variable karyotypes, rDNA sites, and heterochromatin distributions. Differences were observed especially in taxonomically divergent species, suggesting interspecies chromosome rearrangements.
- MeSH
- fylogeneze MeSH
- karyotyp * MeSH
- polymorfismus genetický * MeSH
- ribozomální DNA genetika MeSH
- ryby klasifikace genetika MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Lebiasinidae fishes have been historically neglected by cytogenetical studies. Here we present a genomic comparison in eleven Lebiasinidae species, in addition to a review of the ribosomal DNA sequences distribution in this family. With that, we develop ten sets of experiments in order to hybridize the genomic DNA of representative species from the genus Copeina, Copella, Nannostomus, and Pyrrhulina in metaphase plates of Lebiasina melanoguttata. Two major pathways on the chromosomal evolution of these species can be recognized: (i) conservation of 2n = 36 bi-armed chromosomes in Lebiasininae, as a basal condition, and (ii) high numeric and structural chromosomal rearrangements in Pyrrhulininae, with a notable tendency towards acrocentrization. The ribosomal DNA (rDNA) distribution also revealed a marked differentiation during the chromosomal evolution of Lebiasinidae, since both single and multiple sites, in addition to a wide range of chromosomal locations can be found. With some few exceptions, the terminal position of 18S rDNA appears as a common feature in Lebiasinidae-analyzed species. Altogether with Ctenoluciidae, this pattern can be considered a symplesiomorphism for both families. In addition to the specific repetitive DNA content that characterizes the genome of each particular species, Lebiasina also keeps inter-specific repetitive sequences, thus reinforcing its proposed basal condition in Lebiasinidae.
- MeSH
- Characiformes genetika MeSH
- chromozomy genetika MeSH
- genom * MeSH
- molekulární evoluce * MeSH
- repetitivní sekvence nukleových kyselin MeSH
- ribozomální DNA genetika MeSH
- rybí proteiny genetika MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
A total of 22 specimens of whiting Merlangius merlangus (L.) (Teleostei, Gadidae) from the northern Oresund, Denmark were examined for Myxosporea. Zschokkella hildae Auerbach, 1910 (Myxidiidae), Gadimyxa sp. (Parvicapsulidae) and a species of Bipteria occurred in the renal tubules of 9%, 18% and 68% whiting, respectively. Immature spores of the Bipteria species are very similar to spores of Myxoproteus formosus Kovaleva et Gaevskaya, 1979 originally described from the urinary system of whiting from the Celtic Sea. We therefore consider Bipteria sp. from whiting in Denmark conspecifi c with M. formosus and propose Bipteria formosa (Kovaleva et Gaevskaya, 1979) comb. n. The spore of Bipteria formosa is described in detail and compared with other Bipteria spp. The phylogenetic position of B. formosa, based on partial 18S rDNA sequences, is closest to Leptotheca fugu Tun, Yokoyama, Ogawa et Wakabayashi, 2000 and the Sphaerosporidae.
BACKGROUND: Lake Tana is the largest lake in Ethiopia and the source of the Blue Nile. The lake harbours unique endemic cyprinid fish species, as well as the commercially important endemic Nile tilapia subspecies Oreochromis niloticus tana and the North African catfish Clarias gariepinus. Its endemicity, especially within the Labeobarbus radiation, its conservation importance and its economic indispensability attract scientific interest to the lake's ichthyofauna. Fish parasites of Lake Tana, however, are hitherto poorly known, and no formal report exists on its monogenean flatworms. For sustainable aquaculture and fisheries development, it is essential to study monogenean fish parasites in these economically most important fish species. Moreover, it remains to be verified whether this unique ecosystem and its endemicity gave rise to a distinct parasite fauna as well. RESULTS: Nile tilapia and North African catfish hosts were collected from Lake Tana in 2013. Nine species of monogenean parasites of two orders, Gyrodactylidea Bychowsky, 1937 and Dactylogyridea Bychowsky, 1937, were recovered. Gyrodactylus gelnari Přikrylová, Blažek & Vanhove, 2012, Macrogyrodactylus clarii Gussev, 1961, Quadriacanthus aegypticus El-Naggar & Serag, 1986 and two undescribed Quadriacanthus species were recovered from C. gariepinus. Oreochromis niloticus tana hosted Cichlidogyrus cirratus Paperna, 1964, C. halli (Price & Kirk, 1967), C. thurstonae Ergens, 1981 and Scutogyrus longicornis (Paperna & Thurston, 1969). CONCLUSIONS: Except for M. clarii, all species represent new records for Ethiopia. This first study on the monogenean fauna of Lake Tana revealed that the lake's North African catfish, as well as its endemic Nile tilapia subspecies, harbour parasites that are known from these host species elsewhere in Africa.
- MeSH
- cestodózy parazitologie veterinární MeSH
- cichlidy parazitologie MeSH
- jezera parazitologie MeSH
- nemoci ryb parazitologie MeSH
- ploštěnci klasifikace genetika izolace a purifikace fyziologie MeSH
- potrava z moře (živočišná) ekonomika parazitologie MeSH
- sumci parazitologie MeSH
- žábry parazitologie MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Etiopie MeSH
