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1.
《Journal of bryology》2013,35(4):300-303
Abstract

Pseudocrossidium perpapillosum M.J.Cano & J.A.Jiménez is described and illustrated as a new South American species from Argentina and Chile. It differs from other species of Pseudocrossidium R.S.Williams by the costa excurrent in an awn, elliptical in cross-section, with 4–5(6) guide cells, marginal laminal cells differentiated with rounded, thin-walled and papillose cells, paracostal distal cells with 1–2(4) bi- to quadrifurcate, long papillae, and perichaetial leaves differentiated.  相似文献   

2.
Three species of the red algal genus Herposiphonia (Ceramiales, Rhodomelaceae) found in Japan are described, and taxonomic features of the genus are discussed. Herposiphonia crassa Hollenberg is reported from Japan for the first time and is characterized by thick axes (200–350 µm in diameter) and determinate branches (100–200 µm in diameter), relatively short determinate laterals (400–1200 µm in length) with a large number of periaxial cells (15–19 per segment) and three (occasionally two or four) vigorously developed (1.8–2.5 mm in length by 50–75 µm in diameter basally) trichoblasts on each determinate lateral. Herposiphonia elongata Masuda et Kogame is also reported from Japan for the first time and is characterized by the conspicuous thickening growth of cystocarp‐bearing branches and spermatangial branches with an elongated sterile tip. Some newly found features of Herposiphonia fissidentoides (Holmes) Okamura are presented: the rhizoid production from the central portion of parental periaxial cells in addition to the distal end, virtual absence of vegetative trichoblasts, production of procarpial trichoblasts and spermatangial branches on fertile determinate branches on short indeterminate laterals, cystocarps sometimes with a short spur, and extremely large tetrasporangia.  相似文献   

3.
Asplenium sect. Thamnopteris is a morphologically distinct group within Asplenium, however, the species delimitation within the section is difficult. To evaluate the utility of spore morphology in the taxonomy of Asplenium sect. Thamnopteris, we examined 64 samples representing ca 25 species using scanning electron microscopy. The results show that the spores are monolete and ellipsoidal in shape, and range between 35.7–50.1 × 24.1–32.4 µm in size. The perispore is morphologically very diverse but relatively stable within species. Based on the morphology of spores, we discuss the species concept of A. nidus L. and A. phyllitidis D. Don, propose a new combination (A. latibasis) for Neottopteris latibasis Ching, and treat A. phyllitidis subsp. malesicum Holttum, N. latibasis, N. latipes Ching ex S. H. Wu, and N. subantiqua Ching ex S. H. Wu as new synonyms. A key to all known species of sect. Thamnopteris is provided using characters of spore morphology.  相似文献   

4.
5.
The microsporidium parasitizing Inland Bearded Dragons Pogona vitticeps, and developing primarily in macrophages within foci of granulomatous inflammation of different organs, is described as a new species Encephalitozoon pogonae. Establishing the new species was based on sequencing the ITS‐SSUrDNA region of the ribosomal gene and consequent SSUrDNA‐inferred phylogenetic analyses, as well as on comparison of pathogenesis, host specificity, and ultrastructure among Encephalitozoon species and isolates. The new species is closely related to E. lacertae and E. cuniculi. Analysis of the literature suggests that this microsporidium has been reported previously as an unidentified microsporidian species or isolate of E. cuniculi and may represent a common infection in bearded dragons. All stages of E. pogonae develop in parasitophorous vacuoles. Uninucleate spores on methanol‐fixed smears measured 2.1 × 1.1 μm, range 1.7–2.6 × 0.9–1.7 μm; on ultrathin sections spores measured 0.8–1.1 × 1.8–2.2 μm. Ultrastructural study revealed 3–6 polar filament coils, a mushroom‐shaped polar disk, and a polar sac embracing half of the volume occupied by the lamellar polaroplast. In activated spores, polar filament everted eccentrically. The overall morphology and intracellular development of E. pogonae were similar to other Encepahalitozoon spp. We also review the existing data on microsporidia infecting reptiles.  相似文献   

6.
Egg capsule morphology of five Hong Kong rocky shore littorinids   总被引:1,自引:1,他引:0  
Y. M. Mak 《Hydrobiologia》1995,309(1-3):53-59
  相似文献   

7.
《Journal of bryology》2013,35(4):467-474
Abstract

A new species, Acaulon eremicola is described from aridcentral Australia. It differs from A. muticum and A. integrifolium in the leaf with longer cells and longer usually downwardly curved acuminate apex with twisted arista, the strongly incurled leaf margins when dry, and different spore pattern.  相似文献   

8.
Rhizoglomus venetianum, a new arbuscular mycorrhizal fungal species, has been isolated and propagated from a heavy metal-contaminated site in Sacca San Biagio island, downtown Venice, Italy. Interestingly, under the high levels of heavy metals occurring in the site, the new fungus was able to grow only intraradically. In greenhouse trap and single species cultures under low heavy metal levels, the fungus produced innumerous spores, clusters, and sporocarps extraradically, which were formed terminally on subtending hyphae either singly, in small spore clusters, or, preferably, in loose to compact non-organized sporocarps up to 2500?×?2000?×?2000 μm. Spores are golden-yellow to bright yellow brown, globose to subglobose to rarely oblong, 75–145?×?72–140 μm in diameter, and have four spore wall layers. Morphologically, the new fungus is similar to R. intraradices, and phylogenetically, it forms a monophyletic clade next to R. irregulare, which generally forms irregular spores and lacks, like R. intraradices, the flexible innermost wall layer beneath the structural/persistent third wall layer. A key for the species identification is presented comprising all 18 Rhizoglomus species, so far described or newly combined.  相似文献   

9.
The present work describes the design and synthesis of a novel series of 1,3-diaryl-4-sulfonamidoarylpyrazole derivatives 1a–q and 2a–q and their in vitro biological activities. The target compounds were evaluated for antiproliferative activity against NCI-60 cell line panel. Compounds 1c, 1g, 1k–m, 1o, 2g, 2h, 2k–m, 2o, and 2q showed the highest mean inhibition percentages at 10 µM single-dose testing and were selected to be tested at 5-dose mode. The ICs50 of the most potent compounds were determined over the 60 cell lines. Compound 2l exhibited the strongest activity against different cell lines with IC50 0.33 µM against A498 renal cancer cell line. Compound 2l was tested over a panel of 20 kinases to determine its molecular target(s), and its IC50 values over the most sensitive kinases were defined. In vitro stability and in vivo pharmacokinetic profile of compound 2l was also investigated.  相似文献   

10.
A new series of pyrazolo[3,4-d]pyrimidine-6-one derivatives (2a–2j) were prepared by using the Biginelli multicomponent cyclocondensation of 3-methyl-1-phenyl-1H-pyrazol-5(4H)-one (1a), different aromatic aldehydes, and urea with a catalytic amount of HCl at reflux temperature. These compounds were characterized by IR, 1H NMR, 13C NMR, and Mass spectral data. In vitro antiamoebic activity was performed against HM1:IMSS strain of Entamoeba histolytica. The results showed that the compounds 2b, 2i, and 2j with IC50 values of 0.37 µM, 0.04 µM, and 0.06 µM, respectively, exhibited better antiamoebic activity than the standard drug metronidazole (IC50?=?1.33 µM). The toxicological studies of these compounds on human breast cancer MCF-7 cell line showed that the compounds 2b, 2i, and 2j exhibited >80% viability at the concentration range of 1.56–50 µM.  相似文献   

11.
Microbial resistance to the available drugs poses a serious threat in modern medicine. We report the design, synthesis and in vitro antimicrobial evaluation of new functionalized 2,3-dihydrothiazoles and 4-thiazolidinones tagged with sulfisoxazole moiety. Compound 8d was most active against Bacillis subtilis (MIC, 0.007?µg/mL). Moreover, compounds 7cd and 8c displayed significant activities against B. subtilis and Streptococcus pneumoniae (MIC, 0.03–0.06?µg/mL and 0.06–0.12?µg/mL versus ampicillin 0.24?µg/mL and 0.12?µg/mL; respectively). Compounds 7a and 7cd were highly potent against Escherichia coli (MIC, 0.49–0.98?µg/mL versus gentamycin 1.95?µg/mL). On the other hand, compounds 7e and 9c were fourfolds more active than amphotericin B against Syncephalastrum racemosum. Molecular docking studies showed that the synthesized compounds could act as inhibitors for the dihydropteroate synthase enzyme (DHPS). This study is a platform for the future design of more potent antimicrobial agents.  相似文献   

12.
《Journal of bryology》2013,35(4):292-296
Atrichum laoshanense Y.-J.Yi &; S.He, a new species of Polytrichaceae from Laoshan mountain in Shandong Province, eastern China, is described and illustrated. The new species resembles, and is related to A. angustatum (Brid.) Bruch &; Schimp., but differs in the presence of stellately papillose median leaf cells, multicellular laminal teeth with well-defined outgrowths of pedestal cells on the distal dorsal lamina, and papillose stem epidermal cells. An updated key to species of Atrichum in China is presented.  相似文献   

13.
14.
Haplodontium zangii X.R.Wang &; J.C.Zhao, a new moss species from Xizang, China, is described and illustrated. Previously, specimens of H. zangii have been identified as Mielichhoferia himalayana Mitt. However, H. zangii is distinctly different from M. himalayana in having excurrent costae with short awns (vs long denticulate awns), short-pyriform capsules, 0.8–1?mm (vs long-pyriform capsules, 2.5–3?mm), and densely papillose exostome teeth (vs smooth or vertically striped exostome teeth). Haplodontium zangii is similar to H. macrocarpum (Hook.) J.R.Spence, which was traditionally placed in Mielichhoferia Nees &; Hornsch. as M. macrocarpa (Hook.) Bruch &; Schimp. The main differences between H. zangii and H. macrocarpum are in the morphology of the leaves, capsules, guide cells, and stomata. Mielichhoferia himalayana and another Chinese species of Mielichhoferia, M. sinensis Dix., are also transferred to Haplodontium Hampe, a new genus in the bryoflora of China, as H. himalayanum (Mitt.) X.R.Wang &; J.C.Zhao and H. sinensis (Dix.) X.R.Wang &; J.C.Zhao. A morphological comparison and a key to the three species of Haplodontium in China as well as to H. macrocarpum, a species that is likely to be found in China, are provided.  相似文献   

15.
IN peripheral nerve, most axons with diameters of less than 1 µm do not have myelin sheaths, while most fibres more than 1 µm in diameter are myelinated1,2. In the central nervous system, axons as small as 0.2 µm in diameter may be myelinated2–5. In his paper on the effects of myelin on conduction velocity, Rushton6 concluded that 1 µm is the “critical diameter” above which “myelin increases conduction velocity” and below which “conduction is faster without myelination”. This conclusion is referred to widely (see, for example, refs. 7–9). In this communication we demonstrate that the analysis leading to this conclusion is based on morphological data10 which do not apply either to central or to peripheral fibres, so that myelinated fibres considerably smaller than 1 µm might be expected to conduct more rapidly than non-myelinated fibres of similar size.  相似文献   

16.
17.
Two species of the marine sand-dwelling dinoflagellate genus Cabra were found in epiphytic assemblages on macrophytes from Peter the Great Bay of the Sea of Japan: the type species of the genus Cabra matta and a new species Cabra levis sp. nov. The new species possesses all characteristics of the genus, e.g. the same plate formula (APC 3′ 1a 5′′ 3c 6s 5′′′ 1′′′′), and is 29.0–42.0 µm long and 24.6–37.8 µm deep. It differs from other Cabra species by its more rounded shape, in lacking a spine on the dorsal side of the cell and a pointed flange on plate 1′′′, in having nearly smooth thecal plates as well as by the position of the epithecal plates. Some details of the sulcal construction of Cabra species are described for the first time. Cabra levis and C. matta were found on macrophytes throughout the year. As both species occurred more often on macrophytes than in near-shore sand, they are epiphytic rather than sand-dwelling.  相似文献   

18.
19.
The ciliate genus Chlamydodon is characterized by a unique cross-striated band (CSB) along the cell perimeter. To date, more than 15 nominal species have been assigned to this genus, all of which are exclusively from marine or brackish water. In the present work, we have revised the genus according to the available data and suggest an illustrated key to aid species diagnosis. In addition, the systematic relationships of chlamydodontid congeners were analysed based on SSU rRNA gene sequences, indicating that all congeners belong to a well-defined clade. Furthermore, we investigated three species from coastal areas of China, including two new species, Chlamydodon wilberti sp. nov. and C. bourlandi sp. nov., using morphological and phylogenetic criteria. Chlamydodon wilberti sp. nov. is characterized by a cell size of 65–105 × 35–60 µm, a complete CSB, and 38–49 somatic kineties. Chlamydodon bourlandi sp. nov. has a cell size of 150–250 × 65–150 µm, a complete CSB, a reddish to violet cell colour, 83–97 somatic kineties, and 40–68 contractile vacuoles. As a further contribution, a well-studied species, C. triquetrus (Müller, 1786) Kahl, 1931, is also re-described.

www.zoobank.org/urn:lsid:zoobank.org:pub:B83A5466-9D2B-4502-9A23-F16A61D48172.  相似文献   


20.
《Journal of bryology》2013,35(3):359-364
Abstract

Fissidens traversii, a new species from Queenslahd, Australia, is characterised by the rounded leaf apex, costa papillose and finishing short of the apex, mamillose, multipapillose cells, short dorsal lamina and vaginant laminae (which usually have a marginal strip of transversely elongated calls in the lower half), reaching almost to the apex of the leaf.  相似文献   

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