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1.
Two new marine diatom species from Argentinean coastal waters, Pleurosigma hinzianum Sterrenburg, Sunesen & Sar, sp. nov. and P. frenguellianum Sunesen, Sterrenburg & Sar, sp. nov., are described. The characters permitting their identification are specified, based on comparison with type material of the morphologically similar species P. amara Stidolph and P. elongatum W. Smith in the light (LM) and scanning electron microscope (SEM). New information on the type material of P. elongatum is presented and its taxonomic concept is emended. The main criteria for separation of the species discussed here are: valve outline, path of the raphe-sternum, raphe angle and angle of intersection of the oblique striae in LM; and external central and terminal raphe fissures, internal details of the central area, external and internal apical structure, and morphology of the hymen-occluded internal pores in SEM. The occurrence of these (and probably other) species in the genus Pleurosigma in net samples is adventitious and not indicative of a true planktonic mode of life.  相似文献   

2.
Two species of Phycodrys, Phycodrys quercifolia (Bory) Skottsberg and Phycodrys profunda E.Y.Dawson were previously recorded from New Zealand. However, an examination of Phycodrys collections from the New Zealand region showed that all were morphologically different from P. quercifolia (Type locality: the Falkland Islands) and P. profunda (Type locality: CA, USA). RbcL sequence analyses established that the New Zealand Phycodrys species formed a natural assemblage within the genus, consisting of three new species: P. novae-zelandiae sp. nov., P. franiae sp. nov. and P. adamsiae sp. nov. Phycodrys novae-zelandiae is the largest of the three, up to 20 cm in height, with a distinct midrib and multicellular, opposite to subopposite lateral macroscopic veins. It has entirely monostromatic blades except near the midrib and veins, and its procarp contains a three-celled sterile group one (st1) and a one-celled sterile group two (st2). Phycodrys franiae was previously treated as a cryptic species among herbarium collections of P. ‘quercifolia’. It is smaller (4–11 cm high) with weakly developed midribs and veins, the blade is tristromatic throughout, except at the growing margins, and the procarp consists of a four-celled st1 and a two–three-celled st2. Phycodrys adamsiae, previously reported as P. profunda, is a small decumbent or prostrate plant, 1–8 cm long, with a midrib and inconspicuous lateral veins. The blades are tristromatic with serrated margins, two–four-celled surface spines and multicellular marginal holdfasts that differ from those of Californian specimens. The tetrasporangia are borne on marginal bladelets. Phylogenetic analyses place the New Zealand species in a separate group that is distantly removed from most other Phycodrys species.  相似文献   

3.
4.
Two actinomycete strains isolated from sputum between 1999 and 2001 in Japan were provisionally assigned to the genus Nocardia based on morphological criteria. These isolates were further studied in order to determine their specific taxonomic status. Detailed chemotaxonomic characterization and 16S rDNA gene sequence analysis of these isolates also confirmed that they belong to the genus Nocardia. The 16S rDNA sequence data of the two strains showed that they are most similar to that of Nocardia carnea and Nocardia flavorosea. However, DNA-DNA relatedness data showed that the two strains could be distinguished from N. carnea and N. flavorosea and therefore represented two new species within the genus Nocardia. The designation of the two isolated strains are Nocardia testaceus for IFM 0937(T) (=JCM 12235(T), DSM 44765(T)) and Nocardia senatus for IFM 10088(T) (=JCM 12236(T), DSM 44766(T)).  相似文献   

5.
Two new taxa of Liagoraceae (Nemaliales) are described from Western Australia. Gloiotrichus fractalis gen. et sp. nov. has been collected from 3–20 m depths at the Houtman Abrolhos, Western Australia. Plants are calcified, extremely lubricous, and grow to 17 cm in length. Carpogonial branches are straight, 6 or 7 cells in length, arise from the basal or lower cells of cortical fascicles, and are occasionally compound. Branched sterile filaments of narrow elongate cells arise on the lower cells of the carpogonial branch prior to gonimoblast initiation, at first on the basal cells, then on progressively more distal cells. Following presumed fertilisation the carpogonium divides transversely, with both cells giving rise to gonimoblast filaments. The distal cells of the carpogonial branch then begin to fuse, with fusion progressing proximally until most of the cells of the carpogonial branch are included. As fusion extends, the filaments on the carpogonial branch are reduced to the basal 2 or 3 cells. The gonimoblast is compact and bears terminal carposporangia. Spermatangial clusters arise on subterminal cells of the cortex, eventually displacing the terminal cells. The sequence of pre- and post-fertilisation events occurring in the new genus separates it from all others included in the Liagoraceae, although it appears to have close affinities with the uncalcified genus Nemalion. Ganonema helminthaxis sp. nov. was collected from 12 m depths at Rottnest Island, Western Australia. Plants are uncalcified and mucilaginous, the axes consisting of a few (< 10) primary medullary filaments, each cell of which gives rise to a cortical fascicle at alternate forks of the pseudodichotomies borne on successive medullary cells. Subsidiary (adventitious) filaments and rhizoids comprise the bulk of the thallus. Carpogonial branches are straight, (3-)4(-6) cells in length, arise on the basal 1–4 cells of the cortical fascicles, and are frequently compound. Carposporophytes develop from the upper of two daughter cells formed by a transverse division of the fertilised carpogonium. Ascending and descending sterile filaments girdle the carpogonial branch cells and arise mostly on the supporting cell prior to fertilisation. Ganonema helminthaxis is the first completely non-calcified member of the genus, and its reproductive and vegetative morphology supports the recognition of Ganonema as a genus independent from Liagora. Liagora codii Womersley is a southern Australian species displaying features of Ganonema, to which it is transferred.  相似文献   

6.
Three isolates belonging to the ascomycetous genus Zygotorulaspora were obtained from the fruits of Cornus officinalis and Smilax china, and flowers of Dendranthema zawadskii var. latilobum in Gongju-si, Korea. Phylogenetic Analyses of the LSU D1/D2 domain and ITS region sequences supported the recognition of two new species: Zygotorulaspora cornina sp. nov. (type strain NIBRFGC000500475 = KACC93346PPP) and Zygotorulaspora smilacis sp. nov. (type strain NIBRFGC000500476 = KACC93347PPP). The two novel species revealed no growth on D-Galactose, unlike the other six species in the genus Zygotorulaspora. They are distinguished from each other by their phylogenetic differences and phenotypic characteristics such as assimilation of xylitol, 5-keto-D-gluconate, and ethanol. All species in the genus Zygotorulaspora including the two novel species have phenotypic traits of genus Zygotorulaspora: asci are persistent, sucrose and raffinose are assimilated, and m-inositol is not required for growth, and they are mainly associated with plants.  相似文献   

7.
In a taxonomic study on the ascomycetous yeasts isolated from plant materials collected in tropical forests in Yunnan and Hainan Provinces, southern China, four strains isolated from tree sap (YJ2E(T)) and flowers (YF9E(T), YWZH3C(T) and YYF2A(T)) were revealed to represent four undescribed yeast species. Molecular phylogenetic analysis based on the large subunit (26S) rRNA gene D1/D2 domain sequences showed that strain YJ2E(T) was located in a clade together with Candida haemulonii and C. pseudohaemulonii. Strain YF9E(T) was most closely related to C. azyma and strain YWZH3C(T) to C. sorbophila and C. spandovensis. Strain YYF2A(T) was clustered in a clade containing small-spored Metschnikowia species and related anamorphic Candida species. The new strains differed from their closely related described species by more than 10% mismatches in the D1/D2 domain. No sexual states were observed for the four strains on various sporulation media. The new species are therefore assigned to the genus Candida and described as Candida alocasiicola sp. nov. (type strain, YF9E(T) = AS 2.3484(T) = CBS 10702(T)), Candida hainanensis sp. nov. (type strain, YYF2A(T) = AS 2.3478(T) = CBS 10696(T)), Candida heveicola sp. nov. (type strain, YJ2E(T) = AS 2.3483(T) = CBS 10701(T)) and Candida musiphila sp. nov. (type strain, YWZH3C(T) = AS 2.3479(T) = CBS 10697(T)).  相似文献   

8.
The taxonomic position of two soil isolates, strains A288(T) and A290(T) [provisionally assigned to the genus Actinomadura] was clarified in a polyphasic study. The organisms showed a combination of chemotaxonomic and morphological properties typical of actinomadurae. They also formed distinct phyletic lines in the 16S rRNA Actinomadura gene tree; strain A288(T) was associated with A. nitritigenes whereas strain A290(T) was closely related to a group that consisted of A. citrea, A. coerulea, A. glauciflava, A. luteofluorescens and A. verrucosospora. Strains A288(T) and A290(T) showed key phenotypic features which readily distinguish them from one another and from representatives of related validly described species of Actinomadura. It is proposed that the two organisms be classified as new species of the genus Actinomadura. The names proposed for the new taxa are Actinomadura mexicana (A290(T) = DSM 44485(T) = NRRL B-24203(T)), and Actinomadura meyerii (A288(T) = DSM 44485(T) = NRRL B-24203(T)).  相似文献   

9.
Polysiphonia sensu lato comprises approximately 200 species, which are currently assigned to several different genera. To date, one of these genera, namely, Polysiphonia, has been reported to have 17 species. Here, we describe for the first time P. freshwateri sp. nov. and P. koreana sp. nov. from Uljin and Ulleung Island, Korea, based on morphological and molecular evidence. Polysiphonia freshwateri sp. nov. and P. koreana sp. nov. are characterized by having the typical Polysiphonia features. Polysiphonia freshwateri sp. nov. is further characterized by having abundant trichoblasts, conspicuous scar cells, and tetrasporangia arranged in spiral series. Polysiphonia koreana sp. nov. is further characterized by having very scarce scar cells placed between two pericentral cells, from which cicatrigenous branches arise. The results of our rbcL sequence analyses support the taxonomic placement of P. freshwateri sp. nov. and P. koreana sp. nov. within Polysiphonia.  相似文献   

10.
Four novel yeast species are described, two from decaying mushrooms, viz. Candida cretensis and Candida vadensis, and two from rotten wood, viz. Blastobotrys robertii and Candida scorzettiae. Accession numbers for the CBS and ARS Culture Collections, and GenBank accession numbers for the D1/D2 domains of the large subunit of ribosomal DNA are: B. robertii CBS 10106T, NRRL Y-27775, DQ839395; C. cretensis CBS 9453T, NRRL Y-27777, AY4998861 and DQ839393; C. scorzettiae CBS 10107T, NRRL Y-27665, DQ839394; C. vadensis CBS 9454T, NRRL Y-27778, AY498863 and DQ839396. The GenBank accession number for the ITS region of C. cretensis is AY498862 and that for C. vadensis is AY498864. C. cretensis was the only species of the four that displayed fermentative activity. All four type strains grew on n-hexadecane. C. scorzettiae is the only one of the new species that assimilates some phenolic compounds, viz. 3-hydroxy derivatives of benzoic, phenylacetic and cinnamic acids, but not the corresponding 4-hydroxy acids. This is indicative of an operative gentisate pathway.  相似文献   

11.
Two extremely halophilic archaeal strains GX3(T) and GX26(T) were isolated from the Gangxi marine solar saltern near the Weihai city of Shandong Province, China. Cells from the two strains were pleomorphic and stained Gram-negative, colonies were red-pigmented. Strains GX3(T) and GX26(T) were able to grow at 25-50 °C (optimum 37 °C), at 1.4-5.1M NaCl (optimum 3.1M), at pH 5.5-9.5 (optimum pH 7.0) and neither strain required Mg(2+) for growth. Cells lyse in distilled water and the minimal NaCl concentration to prevent cell-lysis was 8% (w/v). The major polar lipids of the two strains were PA (phosphatidic acid), PG (phosphatidylglycerol), PGP-Me (phosphatidylglycerol phosphate methyl ester) and three major glycolipids (GL1, GL2 & GL3) chromatographically identical to S-TGD-1 (sulfated galactosyl mannosy glucosyl diether), S-DGD-1 (sulfated mannosyl glucosyl diether), and DGD-1 (mannosyl glucosyl diether) respectively, an unidentified lipid (GL4) was also detected in strain GX26(T). Phylogenetic analysis based on 16S rRNA gene revealed that strain GX3(T) and strain GX26(T) formed a distinct clade with the closest relative, Haladaptatus paucihalophilus (89.9-92.4% and 90.4-92.7, respectively). The rpoB' gene similarities between strains GX3(T) and GX26(T), and between the two strains and the closest relative, Halorussus rarus TBN4(T) are 96.5%, 84.3% and 83.9%, respectively. The DNA G+C contents of strain GX3(T) and strain GX26(T) are 67.3 mol% and 67.2 mol%, respectively. The DNA-DNA hybridization value between strain GX3(T) and strain GX26(T) was 44%. The phenotypic, chemotaxonomic and phylogenetic properties suggest that strain GX3(T) and strain GX26(T) represent two novel species in a new genus within the family Halobacteriaceae, Halorubellus salinus gen. nov., sp. nov. (type strain GX3(T)=CGMCC 1.10384(T)=JCM 17115(T)) and Halorubellus litoreus sp. nov. (type strain GX26(T)=CGMCC 1.10386(T)=JCM 17117(T)).  相似文献   

12.
Strains XZ-46A, XZ-105, XZ-129 and XZ-281T isolated from the oral cavities of healthy Tibetan volunteers were revealed to represent two novel ascomycetous yeast species by molecular taxonomic characterizations. Strain XZ-281T was most closely related to Candida humilis , but differed from the type strain of the species by eight (1.2%) substitutions in the 26S rRNA gene D1/D2 domain and by >100 (>20%) mismatches in the internal transcribed spacer (ITS) region. Strains XZ-46A, XZ-105 and XZ-129 had identical or similar D1/D2 and ITS sequences with each other and with strain 17YFT isolated from a leaf of an oak tree ( Quercus sp.). The closest relative of this group was Torulaspora microellipsoides . They differed from the type strain of the species by five (0.9%) substitutions in the D1/D2 domain and >70 (>15%) mismatches in the ITS region. A sexual state was observed in strain 17YFT, but not in the other four oral strains. An anamorphic name Candida pseudohumilis sp. nov. is proposed for strain XZ-281T (=AS 2.3956T=CBS 11404T) and a teleomorphic name Torulaspora quercuum sp. nov. is proposed for strain 17YFT (=AS 2.3768T=CBS 11403T) and the other three oral strains.  相似文献   

13.
SYNOPSIS. Microglomus paxillus is described as a new genus and species of the subclass Protosteliida (Class Eumyceto-zoa). It has been isolated only once from casuarina bark collected in Oahu, Hawaii. The new organism is characterized by a uninucleate ameboid trophic stage that feeds on bacteria and by sporocarps with spike-like stalks terminated by microspo-rangia containing tetrads of ameboid protoplasts or thin-walled spores. No flagellate cells are produced. The tetrads are typically formed by successive bipartition following conjugate nuclear divisions in the sporogen. The cells of the tetrad are at first binucleate but soon become uninucleate as a result of nuclear degeneration. Variations in the process of sporogenesis are described.  相似文献   

14.
Thecadinium inclinatum Balech and four new marine sand‐dwelling species of the dinoflagellate genus Thecadinium are described from the sandy beaches along the coast of Shikoku, Japan. Thecadinium inclinatum is thecate, bilaterally flattened, elliptical in shape, non‐photosynthetic, and measures 55–75 μ in length and 43–59 μ in depth. The epi‐ and hypotheca theca are semielliptical and the thecal surface is smooth with small pores. The plate formula is Po (pore plate), 3′, 7″,?c,?s, 5″′1″′.Thecadinium ovatum sp. nov. is thecate, non‐photosynthetic, bilaterally flattened and almost oval in lateral view. The cell measures 40–50 μm in length and 33–40 μm in depth. The hypotheca has two or three strong antapical spines. The plate formula is 3′, 6″,6c, 5s?, 5″′, 1″′. Thecadinium striatum sp. nov. is thecate, non‐photosynthetic, bilaterally flattened and somewhat elliptical in lateral view. The cell is 33–41 μm long and 23–30 μm deep. Several striae are present on the hypotheca. The plate formula is 3′, 6″, 6c, 5s?, 5″′, 1″″. Thecadinium yashimaense sp. nov. is bilaterally flattened, photosynthetic and elliptical in ventral view. The cell is 44–65 μm long and 23–36 μm wide. The thecal surface is smooth with small pores. he cingulum forms a steep left–handed spiral. The plate formula is Po, 3′, la, 6″, 5c, 4s, 5″′, 1″′. Thecadinium arenarium sp. nov. is somewhat wedge‐shaped in ventral view, photosynthetic with brownish chloroplasts and almost rounded in cross section. The cingulum forms a steep left‐handed spiral. The cell measures 35–41 μm in length and 25–30 μm in width. The thecal surface is weakly reticulated with small pores. The hypotheca is conical. The plate formula is Po, 3′, la, 6″, 5c, 4s, 5″′, 1″″.  相似文献   

15.
Kořínek  Vladimír  Saha  Ratan K.  Bhattacharya  T. 《Hydrobiologia》1999,392(2):241-247
A new species, Bosmina tripurae is described from South India. The species shares some of the morphological traits with Bosmina fatalis from East and SE Asia, and two other species described recently from North America. They all form a subgeneric group established earlier: subgenus Sinobosmina Lieder 1957. Parthenogenetic females of the new species are superficially similar to the species Bosmina longirostris, which occurs on Indian subcontinent, only in northern high mountain lakes. All reports of the latter species from Indian lowlands are either Bosmina tripurae or some other not yet described species. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

16.
The genus Pseudozyma is ustilaginomycetous anamorphic yeasts, and are mainly isolated from plants. We isolated three Pseudozyma strains from the blood of patients in Thailand. While one isolate was identified as P. antarctica by rDNA sequence analysis, the other two were considered to be new species and were named P. parantarctica and P. thailandica. The three isolates proved to be resistant to 5-flucytosine, and P. thailandica was also resistant to fluconazole and itraconazole. As far as we know, this is the first isolation of Pseudozyma strains from humans. The two new species are described.  相似文献   

17.
Two new species of heliobacteria isolated from cyanobacterial mats of two alkaline sulfidic hot springs are formally described. Strains BR4 and BG29 are assigned to anoxygenic phototrophic bacteria of the familyHeliobacteriaceae, since they possess the unique properties of this taxon: strict anaerobiosis, formation of bacteriochlorophyllg, the lack of extensive intracytoplasmic membranes and chlorosomes, an unusual cell wall structure, and phylogenetic relatedness to the low G+C gram-positive eubacteria. Based on the 16S rDNA sequence similarity, strains BR4 and BG29 are assigned to the genusHeliobacterium and described as two new species of this genus:Heliobacterium sulfidophilum sp. nov. andHeliobacterium undosum sp. nov. The G+C content of the DNA is 51.3 mol % inHbt. sulfidophilum and 57.2-57.7 mol % inHbt. undosum. The cells ofHbt. sulfidophilum are rods, and the cells ofHbt. undosum are slightly twisted spirilla or short rods. Both new bacteria are motile by peritrichous flagella.Hbt. sulfidophilum produces endospores. The new bacteria are strict anaerobes growing photoheterotrophically on a limited range of organic compounds. In the dark, they can switch from photosynthesis to the slow fermentation of pyruvate. Biotin is required as a growth factor. Both species are highly tolerant to sulfide (up to 2 mM at pH 7.5) and oxidize it photoheterotrophically to elemental sulfur; photoautotrophic growth was not observed. The temperature optimal for growth ofHbt. sulfidophilum andHbt undosum is 30–35‡C, and the optimal pH is 7–8.  相似文献   

18.
This paper deals with the epidermal structure of Rhaphidopteris latiloba sp. nov. and R. liuzhiensis sp. nov. The specimens were collected from the upper Triassic caol series of Liuzhi district, Guizhou province. In R. latiloba, the ultimate pinna are wedge-shaped, segments are wider (about 0.2–0.25cm). The leaf is amphistomatic. Stomatal apparatus are haplocheilic, with sunken guard cells and irregullarly orientated stomata, 28–30 per sq. mm in the lower epidermis. In R. liuzhiensis, leaf is tripinnate, oval. Ultimate pinna lanceolate. Segments are narrow about lmm in width. Stomatal apparatus are haplocheilic and round-oval in shape with irregularly orientated stomata 35–40 per sq. mm in the lower epidermis.  相似文献   

19.
Two strains designated strains L-1T and L-9T were isolated from activated sludge of a treatment plant that receives wastewater from the tannery industry contaminated with chromium. Phylogenetic analysis showed that the organisms represented two new species of the genus Leucobacter. Strains L-1T and L-9T could be distinguished from the type strain of L. komagatae and from the type strain of “L. albus” by the B-type peptidoglycan composition, fatty acid composition, several phenotypic and physiological characteristics. The major fatty acids of the organisms were iso- and anteiso-branched C15:0 and C17:0, straight-chain C16:0 was also found in relatively high proportions. The organisms were halotolerant, grew in medium containing 9% NaCl, and all strains, including the type strain of L. komagatae grew in medium containing 5 mM Cr(VI). On the basis of the distinct peptidoglycan composition, 16S ribosomal DNA sequence analysis, percentage of DNA-DNA reassociation values, and phenotypic characteristics we are of the opinion that strain L-1T represents a new species of the genus Leucobacter for which we propose the name Leucobacter chromiireducens and that strain L-9T represents an additional new species of the same genus for which we propose the name Leucobacter aridicollis.  相似文献   

20.
A strictly aerobic, Gram-positive, motile, coccoid-shaped, halotolerant actinobacterium (10% NaCl, w/v), designated MSL-23T, was isolated from a soil sample on Bigeum Island, Korea. Results of 16S rRNA gene sequence analysis indicated that the isolate belonged to the genus Nocardioides, with the highest sequence similarity (95.63%) being to Nocardioides kribbensis KCTC 19038T. The major menaquinone was MK-8(H4), and the predominant cellular fatty acids were i-C16:0, ai-C17:0, C18:1 ω9c and 10-methyl-C16:0. The DNA G+C content was 69.7 mol%. The 16S rRNA gene sequence of strain MSL 23T and its chemotaxonomic properties showed it to be unique in the genus Nocardioides. Phenotypic characteristics distinguished strain MSL-23T from other Nocardioides species. On the basis of the phenotypic, chemotaxonomic and phylogenetic data strain MSL-23T represents a novel species, for which the name Nocardioides halotolerans sp. nov. is proposed, with MSL-23T (=KCTC 19274T=DSM 19273T) as the type strain.  相似文献   

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