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1.
Two new species of mysids are described. Rhopalophthalmus constrictussp. nov. is unique in having a well-produced triangular rostralplate, pleural plates on the anterior five abdominal somitesand prominent constriction at the distal end of the telson.Australomysis reubeni sp. nov. is distinguished by its rostrum,telson, fourth male pleopod and modified setae on the carpopropodalsegment.  相似文献   

2.
Chrysochromulina brachycylindra sp. nov. is described by means of transmission electron microscopy of shadowcast whole mounts prepared from wild material collected from Finnish coastal waters. The suhspherical cell carries plate-scales and cylinder-scales. The scales are large enough to render possible a light microscopical identification of this species from dry preparations. Based on scale morphology it is evident that C. brachycylindra is closely related to C. pachycylindra Manton, Oates & Course. In addition to the findings from the Baltic Sea the new species is also reported from the Andaman Sea, SW Thailand.  相似文献   

3.
Two new species of aerobic, gram-negative, peritrichously flagellated or nonmotile marine bacteria usually forming star-shaped aggregates were isolated from northeastern Atlantic Ocean bottom sediments. These organisms resembled eight star-shaped-aggregate-forming bacterial species from the Baltic Sea originally ascribed to the genus Agrobacterium but not included on the Approved Lists of Bacterial Names because of their questionable relationships to true agrobacteria. These two sets of star-shaped-aggregate-forming bacteria were compared by means of phenotypic data, DNA base compositions, DNA-DNA relatedness, and one-dimensional electrophoretic analysis of low-molecular-weight RNAs (5S rRNA and tRNA). According to the results of genotyping, the northeastern Atlantic Ocean isolates and three of the Baltic Sea species formed a group of closely related bacteria that could not be excluded from the genus Agrobacterium with certainty. Until more genotypic data are available, these five marine species are regarded as a distinct subdivision of the genus Agrobacterium consisting of Agrobacterium atlanticum sp. nov. (type strain, 1480T = DSM 5823T), A. meteori sp. nov. (type strain, 1513T = DSM 5824T), A. ferrugineum sp. nov. nom. rev. emend. (type strain, ATCC 25652T), A. gelatinovorum sp. nov. nom. rev. emend. (type strain, ATCC 25655T), and A. stellulatum sp. nov. nom. rev. emend. (type strain, ATCC 15215T). "A. aggregatum" proved to be a later subjective synonym of A. stellulatum, which had priority. The remaining four Baltic Sea species, "A. agile," "A. kieliense," "A. luteum," and "A. sanguineum," could not be placed in the new subdivision of Agrobacterium.  相似文献   

4.
The planktonic phototrophic dinoflagellate Alexandrium pohangense sp. nov. isolated from the coastal waters off Korea is described from living and fixed cells by light and scanning electron microscopy (SEM). DNA sequence data were collected from the small subunit (SSU), the large subunit (LSU), internal transcribed spacer regions (ITS1 and ITS2), and 5.8S of the ribosomal DNA (rDNA). The SSU and LSU rDNA sequences of the new dinoflagellate were 4–7% and 14–17%, respectively, different from those of Alexandrium minutum, Alexandrium ostenfeldii, Alexandrium tamutum, Alexandrium margalefii, and Alexandrium pseudogonyaulax, the most closely related species. In addition, the 5.8S rDNA sequence of the new dinoflagellate was also 12% different from those of A. minutum, A. ostenfeldii, A. tamutum, and Alexandrium peruvianum. In a phylogenetic tree based on LSU rDNA sequences, A. pohangense formed a clade with A. margalefii, and this clade was clearly distinct from the clade of A. minutum, Alexandrium diversaporum, A. tamutum, Alexandrium leei, A. ostenfeldii, and Alexandirum andersoni. Moreover, in a phylogenetic tree based on SSU rDNA sequences, A. pohangense was positioned at the base of the clade containing A. leei and A. diversaporum. Morphological analysis showed that A. pohangense has a Kofoidian plate formula of Po, 4′, 6′′, 6c, 8s, 5′′′, and 2′′′′, which confirmed its assignment to the genus Alexandrium. This dinoflagellate has a wide rectangular 1′ plate, the upper left side of which is slightly bent, protruding, and touching the 2′ plate, unlike A. margalefii, which has a wide rectangular 1′ plate that does not touch the 2′ plate, or A. pseudogonyaulax and Alexandrium camurascutulum, which have a narrower elongated pentagonal 1′ plate that touches the 2′ plate. Furthermore, the 1′ plate of A. pohangense meets the 1′′ plate as a straight vertical line, whereas that of A. camurascutulum meets the 1′′ plate as an inclined line because it is lifted by the intrusion of the 1′′ plate. In addition, A. pohangense had a relatively small ventral pore whose majority was located on the 4′ plate, unlike A. margalefii or A. pseudogonyaulax, which have a relatively large ventral pore whose majority is located on the 1′ plate. Furthermore, A. pohangense had pores of two different sizes on the cell surface, unlike A. margalefii and A. pseudogonyaulax, which have similar pores of only one size. On the basis of morphological and phylogenetic criteria, it is proposed that this is a new species of the genus Alexandrium.  相似文献   

5.
Small coastal dolphins endemic to south-eastern Australia have variously been assigned to described species Tursiops truncatus, T. aduncus or T. maugeanus; however the specific affinities of these animals is controversial and have recently been questioned. Historically 'the southern Australian Tursiops' was identified as unique and was formally named Tursiops maugeanus but was later synonymised with T. truncatus. Morphologically, these coastal dolphins share some characters with both aforementioned recognised Tursiops species, but they also possess unique characters not found in either. Recent mtDNA and microsatellite genetic evidence indicates deep evolutionary divergence between this dolphin and the two currently recognised Tursiops species. However, in accordance with the recommendations of the Workshop on Cetacean Systematics, and the Unified Species Concept the use of molecular evidence alone is inadequate for describing new species. Here we describe the macro-morphological, colouration and cranial characters of these animals, assess the available and new genetic data, and conclude that multiple lines of evidence clearly indicate a new species of dolphin. We demonstrate that the syntype material of T. maugeanus comprises two different species, one of which is the historical 'southern form of Tursiops' most similar to T. truncatus, and the other is representative of the new species and requires formal classification. These dolphins are here described as Tursiops australis sp. nov., with the common name of 'Burrunan Dolphin' following Australian aboriginal narrative. The recognition of T. australis sp. nov. is particularly significant given the endemism of this new species to a small geographic region of southern and south-eastern Australia, where only two small resident populations in close proximity to a major urban and agricultural centre are known, giving them a high conservation value and making them susceptible to numerous anthropogenic threats.  相似文献   

6.
A new species of the dinoflagellate genus Gymnodinium Stein, previously considered a member of Katodinium Fott, is characterized from two marine benthic habitats in tropical northern Australia. Gymnodinium dorsalisulcum comb. nov. was found to be very abundant at times, and in culture produced large quantities of mucus. We analyzed two regions of ribosomal DNA from this species (partial large subunit and complete small subunit sequences), using Bayesian analysis and phylogenetic models appropriate to alignments of ribosomal RNA genes. We compared it to eight species of the ‘true’Gymnodinium clade and to other dinoflagellates. The results show that it is a member of the Gymnodinium clade, and is closely related to Gymnodinium impudicum and G. chlorophorum. Katodinium was originally defined as having cells with an epitheca that is much larger than the hypotheca. However, this character is clearly inadequate, and the genus requires a re‐investigation to determine the apomorphies of the type species.  相似文献   

7.
8.
W.R. Miller  T.R. Mason 《Ichnos》2013,20(3):195-215
Three new ichnotaxa are described from Cenozoic paralic to continental sediments on the west coast of South Africa. Stellavelum arborensis and Stellavelum uncinum are assigned to a mixed Skolithos and Cruziana ichnofacies and Termitichnus namibiensis is assigned to the Termitichnus ichnofacies. An interpretation of the sedimentary record shows that the Stellavelum trace makers were probably sediment ingesting annelids that lived in dense colonies in sheltered lagoonal environments during Neogene times. The Termitichnus namibiensis trace fossils are interpreted as actively backfilled termite nests which form an early to mid‐Pleistocene palimpsest, terrestrial ichnofabric which is superimposed on the older marine sediments.  相似文献   

9.
A novel Gram-stain-negative, rod-to-spiral-shaped, oxidase- and catalase- positive and facultatively aerobic bacterium, designated HS6T, was isolated from marine sediment of Yellow Sea, China. It can reduce nitrate to nitrite and grow well in marine broth 2216 (MB, Hope Biol-Technology Co., Ltd) with an optimal temperature for growth of 30–33 °C (range 12–45 °C) and in the presence of 2–3 % (w/v) NaCl (range 0.5–7 %, w/v). The pH range for growth was pH 6.2–9.0, with an optimum at 6.5–7.0. Phylogenetic analysis based on 16S rRNA gene sequences demonstrated that the novel isolate was 93.3 % similar to the type strain of Neptunomonas antarctica, 93.2 % to Neptunomonas japonicum and 93.1 % to Marinobacterium rhizophilum, the closest cultivated relatives. The polar lipid profile of the novel strain consisted of phosphatidylethanolamine, phosphatidylglycerol and some other unknown lipids. Major cellular fatty acids were summed feature 3 (C16:1 ω7c/iso-C15:0 2-OH), C18:1 ω7c and C16:0 and the main respiratory quinone was Q-8. The DNA G+C content of strain HS6T was 61.2 mol %. Based on the phylogenetic, physiological and biochemical characteristics, strain HS6T represents a novel genus and species and the name Motiliproteus sediminis gen. nov., sp. nov., is proposed. The type strain is HS6T (=ATCC BAA-2613T=CICC 10858T).  相似文献   

10.
11.
Luo  Hai-Min  Feng  Jun-Hui  Li  Liang-Hui  Li  Meng-Meng  Liu  Ru-Qin  Chen  Fu  Lin  Ying  Li  Wen-Jun  Qu  Ping-Hua  Xiao  Min 《Antonie van Leeuwenhoek》2021,114(7):1079-1089

Six aerobic Gram-negative bacteria were isolated from seawater in Guangdong Province, P.R. China. Cells were observed to be Gram-negative, aerobic, non-motile and non-spore forming. Growth of the designated type strain 19X3-30T occurred at a temperature range of 14–37 °C (optimum, 28 °C), a pH range of 6.0–8.0 (optimum, pH 7) and up to 7.5% NaCl (optimum, 1.5%; w/v), and was enhanced by CO2 and L-cysteine supplementation. The major polar lipids identified in strain 19X3-30T were diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylglycerol. The principal cellular fatty acids profile showed the presence of anteiso-C15:0, anteiso-C17:0 and C18:0 (>?8% of total fatty acids), and the respiratory quinone was ubiquinone 8 (UQ-8). According to the analysis of 16S rRNA gene sequences, these strains represented a novel species within the family Fastidiosibacteraceae, sharing maximum similarities with Cysteiniphilum litorale DSM 101832T (96.6%) and Cysteiniphilum halobium DSM 103992T (95.3%). Phylogenetic dendrograms based on 16S rRNA gene and protein marker genes from the genomic sequences both indicated that the strains formed a monophyletic lineage closely linked to the genus Cysteiniphilum, which was also supported by the UPGMA dendrogram based on the MALDI-TOF MS profile. The genomic DNA G?+?C contents of six strains ranged from 38.0% to 38.1%. Based on different taxonomic genomic metrics, phylogeny and phenotypic features, we propose that the strains warrant the assignment to a novel species, for which the name Cysteiniphilum marinum sp. nov. is proposed. The type strain is 19X3-30T (=?KCTC 82154T?=?CGMCC 1.18585T).

  相似文献   

12.
Two new species from Iceland are described on the basis of physiological profiles and sequence data from the D2 region of LSU rDNA: Cryptococcus tephrensis (type ICE99-IToM Y5, ATCC MYA-1765, CBS 8935, GenBank AF317208) and Cryptococcus heimaeyensis (type ICE99-IToM Y8, ATCC MYA-1759, CBS 8933, GenBank AF370717). The two new species are identifiable from sequence data and can be distinguished from their closest relative, Cryptococcus victoriae, by their higher maximum temperatures for growth, failure to utilize nitrate as sole nitrogen source, and utilization of cadaverine and ethylamine as sole nitrogen sources. Cryptococcus tephrensis is distinguishable from C. heimaeyensis by failure to grow on saccharate as sole source of carbon and energy.  相似文献   

13.
During daily monitoring in Yongho Bay off Busan, Korea in 2019, an isolate of the dinoflagellate genus Heterocapsa was established in clonal culture. Light and electron microscopic examination revealed that the isolate was ellipsoid in shape, exhibiting a thecal plate arrangement (Po, cp, X, 5′, 3a, 7″, 6c, 5s, 5‴, 2ʹʹʹʹ) consistent with most other Heterocapsa species. A large, elongated nucleus was positioned on the left side of the cell, a single reticulate chloroplast was located peripherally, and a single, starch-sheathed, spherical pyrenoid was present in the episome or near the cingulum. Morphologically, the isolate most closely resembles H. circularisquama and H. illdefina. Transmission electron microscopic examination of whole mounts revealed that the isolate had two body scale types, one of which was a complex, three-dimensional, fine structure distinct from other Heterocapsa species, whereas the other simpler type was structurally similar to the scales of H. horiguchii. Molecular phylogeny based on rRNA sequences revealed that the isolate was distantly related to morphologically similar species, but formed a sister lineage to H. horiguchii, a species characterized by a similar body scale morphology. Based on morphological, ultrastructural, and molecular data, we proposed it as a new species, Heterocapsa busanensis sp. nov.  相似文献   

14.
15.
Phenotypic and phylogenetic studies were performed on two myxobacterial strains, SMP-2 and SMP-10, isolated from coastal regions. The two strains are morphologically similar, in that both produce yellow fruiting bodies, comprising several sessile sporangioles in dense packs. They are differentiated from known terrestrial myxobacteria on the basis of salt requirements (2-3% NaCl) and the presence of anteiso-branched fatty acids. Comparative 16S rRNA gene sequencing studies revealed that SMP-2 and SMP-10 are genetically related, and constitute a new cluster within the myxobacteria group, together with the Polyangium vitellinum Pl vt1 strain as the closest neighbor. The sequence similarity between the two strains is 95.6%. Based on phenotypic and phylogenetic evidence, it is proposed that these two strains be assigned to a new genus, Haliangium gen. nov., with SMP-2 designated as Haliangium ochraceum sp. nov. (= JCM 11303(T) = DSM 14365(T)), and SMP-10 as Haliangium tepidum sp. nov. (= JCM 11304(T)= DSM 14436(T)).  相似文献   

16.
A genealogical concordance approach was used to delineate strains isolated from Acacia dealbata and Acacia mearnsii root nodules in South Africa. These isolates form part of Bradyrhizobium based on 16S rRNA sequence similarity. Phylogenetic analysis of six housekeeping genes (atpD, dnaK, glnII, gyrB, recA and rpoB) confirmed that these isolates represent a novel species, while pairwise average nucleotide identity (ANIb) calculations with the closest type strains (B. cosmicum 58S1T, B. betae PL7HG1T, B. ganzhouense CCBAU 51670 T, B. cytisi CTAW11T and B. rifense CTAW71T) resulted in values well below 95–96%. We further performed phenotypic tests which revealed that there are high levels of intraspecies variation, while an additional analysis of the nodA and nifD loci indicated that the symbiotic loci of the strains are closely related to those of Bradyrhizobium isolates with an Australian origin. Strain 14ABT (=LMG 31415 T = SARCC-753 T) is designated as the type strain of the novel species for which we propose the name Bradyrhizobium xenonodulans sp. nov.  相似文献   

17.
18.
The status of two mesophilic filamentous actinomycetes isolated from an arid Australian soil sample was determined using a polyphasic taxonomic approach. The isolates had chemical and morphological properties consistent with their classification in the genus Amycolatopsis, assignments that were supported by analysis of 16S rRNA gene sequence data. Isolate SF26T formed a distinct phyletic line and hence was sharply separated from its nearest phylogenetic neighbour, Amycolatopsis sacchari DSM 44468T. In contrast, isolate SF27T formed a subclade in the Amycolatopsis tree with Amycolatopsis vancoresmycina DSM 44592T but was separated readily from the latter by DNA:DNA pairing data. The two isolates were distinguished from one another and from their respective nearest phylogenetic neighbours using a range of phenotypic properties. These data indicate that the two isolates should be recognized as new species in the genus Amycolatopsis. The names proposed for these new taxa are Amycolatopsis bartoniae sp. nov. and Amycolatopsis bullii sp. nov. with isolates SF26T (=NCIMB 14706T = NRRL B-2846T) and SF27T (=NCIMB 14707T = NRRL B-24847T) as the respective type strains.  相似文献   

19.
The taxonomic position of 23 strains isolated from mineral waters and previously grouped in the authentic pseudomonads on the basis of a phenotypic analysis (cluster IX, subclusters XIIIa and XIIIc of VERHILLE, S., ELOMARI, M., COROLER, L., IZARD, D., LECLERC, H. (Syst. Appl. Microbiol, 20, 137-149, 1997) has been genotypically further studied in the present work. On the basis of hybridization results, these strains were gathered into two new genomic groups for which we propose the names of Pseudomonas jessenii sp. nov. (Type strain CIP 105274) and Pseudomonas mandelii sp. nov. (Type strain CIP 105273). Deoxyribonucleic acid relatedness levels showed homologies ranging from 78 to 100% for Pseudomonas jessenii and from 77 to 100% for Pseudomonas mandelii. Furthermore, hybrization rates with 66 representative well characterized species or only partially characterized species of the genus Pseudomonas were below 53%, with delta Tm values of 7 degrees C and more. The mol% G + C content ranged from 57 to 58. The two new species presented basic morphological characteristics common to all pseudomonads. Various phenotypic features, such as denitrification, growth at 4 degrees C or 41 degrees C, trigonelline assimilation, alpha-L-glutamyl-L-histidine arylarmidase activity, growth on benzoate and meso-tartrate were found to differentiate Pseudomonas jessenii from Pseudomonas mandelii and from other Pseudomonas species. Pseudomonas jessenii encompassed a total of 9 strains from both phenotypic groups IX and XIIIa. Pseudomonas mandelii clustered a total of 13 strains from both phenotypic groups IX and XIIIc. Their clinical significance is unknown. The 16S rDNA of each type strain was sequenced and compared with the known sequences of the representative strains of the genus Pseudomonas. A phylogenetic tree was constructed to determine the intrageneric relationships within the genus Pseudomonas.  相似文献   

20.
After a brief exposition to glucose, Thiobacillus acidophilus was isolated from a culture of iron-grown T. ferrooxidans. Physicochemical analysis of its DNA showed a G+C content of 62.9-63.2%. The new isolate grows best at 25-30 degrees C and at pH 3.0. Growth is possible between pH 1.5 and 6.0. Thiobacillus acidophilus is apparently strictly aerobic. Ammonium salts are the only suitable source of nitrogen. The bacterium is a facultative autotroph. In addition to elemental sulfur, it obtains energy from organic compounds such as D-glucose, D-galactose, D-fructose, D-mannitol, D-xylose, D-ribose, D-arabinose, L-arabinose, sucrose, sodium citrate, malic acid,dl-aspartic acid, and dl-glutamic acid. Thiobacillus acidophilus possesses the key enzymes of the tricarboxylic acid (TCA) cycle including NAD-and NADP-linked isocitric dehydrogenase and alpha-ketoglutarate dehydrogenase, and the key enzymes of the hexose monophosphate pathway (glucose-6-phosphate and 6-phosphogluconate dehydrogenase, and fructose 1,6-diphosphate aldolase). NADH oxidase has been found in particulate fraction of extracts. Rhodanese and thiosulfate oxidase have also been detected.  相似文献   

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