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1.
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The study of the morphology of orthothecimorph hyoliths from the Atdabanian (Lower Cambrian) of the Siberian Platform allowed the recognition of the new genus and species Spinitheca sysoievi gen. and sp. nov.  相似文献   

3.
The view of lichens as a symbiosis only between a mycobiont and a photobiont has been challenged by discoveries of diverse associated organisms. Specific basidiomycete yeasts in the cortex of a range of macrolichens were hypothesized to influence the lichens' phenotype. The present study explores the occurrence and diversity of cystobasidiomycete yeasts in the lichen genus Cladonia. We obtained seven cultures and 56 additional sequences using specific primers from 27 Cladonia species from all over Europe and performed phylogenetic analyses based on ITS, LSU and SSU rDNA loci. We revealed yeast diversity distinct from any previously reported. Representatives of Cyphobasidiales, Microsporomycetaceae and of an unknown group related to Symmetrospora have been found. We present evidence that the Microsporomycetaceae contains mainly lichen-associated yeasts. Lichenozyma pisutiana is circumscribed here as a new genus and species. We report the first known associations between cystobasidiomycete yeasts and Cladonia (both corticate and ecorticate), and find that the association is geographically widespread in various habitats. Our results also suggest that a great diversity of lichen associated yeasts remains to be discovered.  相似文献   

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A new genus and species of Kinorhyncha, Franciscideres kalenesos gen. et sp. nov., is described from tidal and subtidal sandy habitats in Brazil. The new genus and species is characterized by an extremely flexible trunk without pachycycli that appears perfectly circular in cross-section, segments 1, 2 and 11 consisting of closed rings and 3 to 10 of single, bent plates with midventral articulations, a neck without placids that resembles an additional segment, densely packed scale-like, cuticular hairs, and a terminal segment with a middorsal spine and two sets of lateral terminal spines, but no midterminal spine. Phylogenetic analyses of 18S rRNA of Franciscideres kalenesos gen. et sp. nov. and 47 other kinorhynch ingroup taxa suggest that the new genus is a basal homalorhagid, whereas comparison of morphological characters indicates affinities between the new genus and the peculiar cyclorhagid Cateria.

http://zoobank.org/urn:lsid:zoobank.org:pub:64E29D97-DE1D-4511-8683-C969DD2EED43  相似文献   

6.
Claude Babin 《Geobios》1982,15(3):423-427
A new generic taxon from the Lower Ordovician,Tromelinodonta, is introduced in the family Lyrodesmatidae (Bivalvia). This new genus is based on the species T. armoricana (De Tromelin & Lebesconte, 1876); it has an intermediate dentition between this of Noradonta with lateral posterior crenulated teeth and this of Lyrodesma with a fan-shaped disposition of the cardinal crenulated teeth; its phylogenetic signification is shortly discussed.  相似文献   

7.
Altenglanerpeton schroederi n. sp. is documented by a skeleton preserved in dorsal view from the Altenglan Formation of the Saar?CNahe Basin. The only known species of this new genus has a massive skull that is slightly longer than wide with a more or less triangular outline, without traces of lateral-line canals, with a small round orbit, very wide interorbital region, and the jugal extending far in front of the orbit. The long, undifferentiated trunk region comprises at least 30 lepospondylous presacral vertebrae. The pelvic girdle, hind limbs, and tail are not preserved. The forelimb is small and poorly ossified. The cladogram supports placement of Altenglanerpeton in the Recumbirostra. The new genus seems closest to Tambaroter, the Goniorhynchidae, and Brachystelechidae, with the largest number of morphological similarities shared with the Ostodolepidae, particularly with Micraroter and Pelodosotis.  相似文献   

8.
Seven members of a new group of rod-shaped hyperthermophilic neutrophilic archaebacteria were isolated from boiling neutral to alkaline solfataric waters from the Azores, Iceland, and Italy. The organisms are strict anaerobes, growing optimally at 100°C. The cells are motile due to peritrichous or bipolar polytrichous flagellation. The isolates grow facultatively chemolithoautotrophically or obligately heterotrophically. Molecular hydrogen or complex organic substances are used as electron donors. During heterotrophic growth, elemental sulfur, thiosulfate, sulfite, l(-)cystine and oxidized glutathione may serve as electron acceptors depending on the individual strain. Elemental sulfur is strictly required as an electron acceptor for autotrophic growth. The G+C content of the DNA is around 46 mol%. The isolates represent a new genus which we have named Pyrobaculum (the fire stick). Two species are described: the facultatively autotrophic Pyrobaculum islandicum (DSM 4184), which is the type species, and the obligately heterotrophic Pyrobaculum organotrophum (DSM 4185).  相似文献   

9.
A taxonomic study was conducted on 16 bacterial strains isolated from wild Adélie penguins (Pygoscelis adeliae) from Seymour (Marambio) Island and James Ross Island. An initial screening by repetitive sequence-based PCR fingerprinting divided the strains studied into four coherent groups. Phylogenetic analysis based on 16S rRNA gene sequences assigned all groups to the genus Corynebacterium and showed that Corynebacterium glyciniphilum and Corynebacterium terpenotabidum were the closest species with 16S rRNA gene sequence similarities between 95.4 % and 96.5 %. Further examination of the strains studied with ribotyping, MALDI-TOF mass spectrometry, comprehensive biotyping and calculation of average nucleotide identity and digital DNA–DNA hybridisation values confirmed the separation of the four groups from each other and from the other Corynebacterium species. Chemotaxonomically, the four strains P5828T, P5850T, P6136T, P7210T representing the studied groups were characterised by C16:0 and C18:1 ω9c as the major fatty acids, by the presence of meso-diaminopimelic acid in the peptidoglycan, the presence of corynemycolic acids and a quinone system with the predominant menaquinone MK-9(H2). The results of this study show that the strains studied represent four new species of the genus Corynebacterium, for which the names Corynebacterium antarcticum sp. nov. (type strain P5850T = CCM 8835T = LMG 30620T), Corynebacterium marambiense sp. nov. (type strain P5828T = CCM 8864T = LMG 31626T), Corynebacterium meridianum sp. nov. (type strain P6136T = CCM 8863T = LMG 31628T) and Corynebacterium pygosceleis sp. nov. (type strain P7210T = CCM 8836T = LMG 30621T) are proposed.  相似文献   

10.
A new dinosaur, Ceratonykus oculatus gen. et sp. nov. (Parvicursoridae, Alvarezsauria), from the Upper Cretaceous (Baruungoyot Formation) of Mongolia is described based on a fragmentary skeleton. It differs from other alvarezsaurians in many characters, including the short femora, long tarsometatarsals, and considerably reduced third metatarsals. The carpometacarpals contain spikelike bones. The natural endocast of the new taxon shows large acoustic tubercles, the ventral position of the optic lobes in the midbrain, and the absence of a vertical flexure at the brain floor. The data obtained cast doubt on the taxonomic position of alvarezsaurians in the Theropoda.  相似文献   

11.
A new genus and species of percoid fishes (Pisces, Perciformes) from the Middle-Eocene Messel-Formation is introduced and delimitated from other palaeogene percoids. A preliminary diagnosis is proposed. As the relationships of this new taxon still remain somewhat imprecise, it is provisionally classified as “Percoidei incertae familiae”.  相似文献   

12.
Two new yeast species of the genus Ambrosiozyma are described on the basis of comparison of nucleotide sequences of large subunit of ribosomal DNA D1/D2 region. Ambrosiozyma kamigamensis and Ambrosiozyma neoplatypodis differ from Ambrosiozyma ambrosiae by 17 nucleotides (3.0%) and 16 nucleotides (2.8%), respectively, out of 565. The two species differ from each other by 13 nucleotides. Ambrosiozyma kamigamensis was isolated from galleries of the ambrosia beetle, Platypus quercivorus, in specimens of Quercus laurifolia and Castanopsis cuspidata located in the southern part of Kyoto, Japan. Ambrosiozyma neoplatypodis was isolated from similar material, but only in Q. laurifolia. Ambrosiozyma kamigamensis can be distinguished from the other Ambrosiozyma species by the inability to assimilate erythritol, whereas A. neoplatypodis can be distinguished by the ability to assimilate both L: -arabinose and nitrate. The type strains of A. kamigamensis and A. neoplatypodis are JCM 14990(T) (=CBS 10899(T)) and JCM 14992(T) (=CBS 10900(T)), respectively. This is the first report of new Ambrosiozyma species since the genus was proposed.  相似文献   

13.
Niveas Rota, new genus, and its two new species, N. agassizi Rota, new species, and N. kone Rota, new species, are described and illustrated. Niveas is assigned to the subfamily Choreutinae based on morphological and molecular data. Niveas agassizi is currently known only from Kenya and only from female specimens. Niveas kone has been found on the Solomon Islands and in Papua New Guinea (PNG). In PNG, larvae of this species have been reared from several species of Ficus (Moraceae). The two species are superficially quite dissimilar from each other. However, they share features in wing pattern and venation, as well as female genitalia, and the molecular data strongly support the monophyly of Niveas.  相似文献   

14.

Background and Objectives

Epitheliocystis, caused by bacteria infecting gill epithelial cells in fish, is common among a large range of fish species in both fresh- and seawater. The aquaculture industry considers epitheliocystis an important problem. It affects the welfare of the fish and the resulting gill disease may lead to mortalities. In a culture facility in Kampala, Uganda, juveniles of the African sharptooth catfish (Clarias gariepinus) was observed swimming in the surface, sometimes belly up, showing signs of respiratory problems. Histological examination of gill tissues from this fish revealed large amounts of epitheliocysts, and also presence of a few Ichthyobodo sp. and Trichodina sp.

Methods and Results

Sequencing of the epitheliocystis bacterium 16S rRNA gene shows 86.3% similarity with Candidatus Piscichlamydia salmonis causing epitheliocystis in Atlantic salmon (Salmo salar). Transmission electron microscopy showed that the morphology of the developmental stages of the bacterium is similar to that of members of the family Chlamydiaceae. The similarity of the bacterium rRNA gene sequences compared with other chlamydia-like bacteria ranged between 80.5% and 86.3%. Inclusions containing this new bacterium have tubules/channels (termed actinae) that are radiating from the inclusion membrane and opening on the cell surface or in neighbouring cells.

Conclusions

Radiation of tubules/channels (actinae) from the inclusion membrane has never been described in any of the other members of Chlamydiales. It seems to be a completely new character and an apomorphy. We propose the name Candidatus Actinochlamydia clariae gen. nov., sp. nov. (Actinochlamydiaceae fam. nov., order Chlamydiales, phylum Chlamydiae) for this new agent causing epitheliocystis in African sharptooth catfish.  相似文献   

15.
Morphology and ethology of the Middle–Late Jurassic oyster “Liostrea” roemeri (Quenstedt) from the Upper Callovian of the Volga Region near Saratov and Middle Volgian of the Subpolar Urals are considered. The inverted shell shape and presence of a beaked umbo on the right valves allow the assignment of these oysters to a new monotypic genus, Argutostrea Kosenko, gen. nov. Features of the internal valve structure examined in only one specimen suggest that the new genus should tentatively be included in the subfamily Pycnodonteinae Stenzel, 1959 of the family Gryphaeidae Vialov, 1936. It is shown that shell morphology of the oyster A. roemeri is connected with transition to dwelling on floating ammonites.  相似文献   

16.
A new monothalamous (single-chambered) soft-walled foraminiferal species, Arnoldiellina fluorescens gen. et sp. nov., was isolated from samples collected in the Gulf of Eilat, Israel. The species is characterized by a small elongate organic theca with a single aperture of allogromiids. It is characterized by the emission of green autofluorescence (GAF) that has so far not been reported from foraminifera. Phylogenetic analysis of a fragment of the 18S rDNA indicates that the species is related to a group of monothalamous foraminiferans classified as clade I. Although the morphology of the new species is very different compared to the other members of this clade, a specific helix in 18S rRNA secondary structure strongly supports this position.  相似文献   

17.
The Anones Lagoon, located in the Island Municipality of Vieques, Puerto Rico (PR), received extensive bombing by the US Navy during military exercises for decades until 2003 when military activities ceased. Here, we employed shotgun metagenomic sequencing to investigate how microbial communities responded to pollution by heavy metals and explosives at this lagoon. Sediment samples (0–5 cm) from Anones were collected in 2005 and 2014 and compared to samples from two reference lagoons, i.e., Guaniquilla, Cabo Rojo (a natural reserve) and Condado, San Juan (PR’s capital city). Consistent with low anthropogenic inputs, Guaniquilla exhibited the highest degree of diversity with a lower frequency of genes related to xenobiotics metabolism between the three lagoons. Notably, a clear shift was observed in Anones, with Euryarchaeota becoming enriched (9% of total) and a concomitant increase in community diversity, by about one order of magnitude, after almost 10 years without bombing activities. In contrast, genes associated with explosives biodegradation and heavy metal transformation significantly decreased in abundance in Anones 2014 (by 91.5%). Five unique metagenome-assembled genomes (MAGs) were recovered from the Anones 2005 sample that encoded genetic determinants implicated in biodegradation of contaminants, and we propose to name one of them as “Candidatus Biekeibacterium resiliens” gen. nov., sp. nov. within the Gammaproteobacteria class. Collectively, these results provide new insights into the natural attenuation of explosive contaminants by the benthic microbial communities of the Anones lagoon and provide a reference point for assessing other similarly impacted sites and associated bioremediation efforts.  相似文献   

18.
The oxytrichid ciliate Architricha indica nov. gen., nov. sp., isolated from the river Yamuna, Delhi, shows a new combination of characters. It possesses a flexible body, 18 frontal-ventral-transverse (FVT) cirri, 3 right and 2 left marginal cirral rows, 6 dorsal bristle rows and 3 caudal cirri (CC). The FVT cirri arise from 6 primordia, which utilize 6 parental cirri in their origin as is typical of Oxytricha species. Multiple marginal rows (MMR) develop through 5 independent marginal primordia arising "within-row", 1 in each parental marginal row. All the 5 marginal rows are thus morphogenetically active. Such a mode of formation of MMR has not been recorded among oxytrichids and has necessitated separation of A. indica at the generic level. Histriculus, on the other hand, has well-known characteristics, viz. rigid body, confluent marginal rows and absence of CC. The morphogenesis of Histriculus histrio has been described by Berger and Foissner [1997. Cladistic relationships and generic characterization of oxytrichid hypotrichs (Protozoa, Ciliophora). Arch. Protistenkd. 148, 125-155]. Reinvestigation of very early stages of development revealed that (i) the FVT cirral primordia utilize kinetosomes from 5 parental FVT cirri, (ii) the primordium II of the proter is of a composite origin: kinetosomes from the oral primordium merge with the primordium II that originates from the buccal cirrus II/2 and (iii) the FVT primordia V and VI for the 2 daughter cells arise sequentially from the parental cirrus V/4. Thus, the genus Histriculus exhibits a new combination of characters with respect to the origin of FVT cirri, an additional pattern to be added to the known 6 patterns of FVT development in oxytrichids [Berger and Foissner, 1997; Berger, H., 1999. Monograph of the Oxytrichidae (Ciliophora, Hypotrichida), Kluwer Academic Publishers, Dordrecht/Boston/London].  相似文献   

19.
20.
A female of Foxtosognus rarus gen. n., sp. n., a new genus and species of copepods, is described from the abyss of the Kuril-Kamchatka Trench. The new genus is placed in the family Arctokonstantinidae, whose diagnosis is emended and supplemented with the following characters: mandibular basis with one to two setae; mandibular endopod one without setae; maxillular distal basal endite plus endopod with two to four setae or without setae. The features that distinguish Foxtosognusgen. n. from other representatives of this family are as follows: mandibular palp with a long endopod segment one, endopod segment two with seven setae, and exopod segment five with two setae; maxillula with distal basal endite lacking setae and separated from endopod bearing three setae; maxillular precoxal arthrite with seven to eight setae and exopod with four setae; maxilliped syncoxa without setae on precoxal endites and endopod of three segments. The genera Sognocalanus and Foxtonia earlier included in the Spinocalanidae are herein transferred to the Arctokonstantinidae.  相似文献   

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