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Ronald Fayer 《Experimental parasitology》2010,124(1):90-143
Amphibians, reptiles, birds and mammals serve as hosts for 19 species of Cryptosporidium. All 19 species have been confirmed by morphological, biological, and molecular data. Fish serve as hosts for three additional species, all of which lack supporting molecular data. In addition to the named species, gene sequence data from more than 40 isolates from various vertebrate hosts are reported in the scientific literature or are listed in GenBank. These isolates lack taxonomic status and are referred to as genotypes based on the host of origin. Undoubtedly, some will eventually be recognized as species. For them to receive taxonomic status sufficient morphological, biological, and molecular data are required and names must comply with the rules of the International Code for Zoological Nomenclature (ICZN). Because the ICZN rules may be interpreted differently by persons proposing names, original names might be improperly assigned, original literature might be overlooked, or new scientific methods might be applicable to determining taxonomic status, the names of species and higher taxa are not immutable. The rapidly evolving taxonomic status of Cryptosporidium sp. reflects these considerations. 相似文献
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Coleman R. Robison 《American journal of botany》1977,64(6):726-732
Dwarf shoots and needle leaves of Pinus triphylla Hollick and Jeffrey and P. quinquefolia Hollick and Jeffrey have been discovered recently in a Late Cretaceous age clay deposit on Martha's Vineyard Island, Massachusetts. Detailed study of these fossils provides further information on the internal construction of the two taxa. This new information permits both species to be compared easily with similar fossil forms from the Upper Cretaceous of Japan as well as with dwarf shoots and needles of modern species of Pinus. As a result, the relationships between Cretaceous pines and the extinct genus Prepinus are found to be less than previously believed. Moreover, the dwarf shoots and needles of Cretaceous members of the genus Pinus appear to be most like those of present-day species included in the subgenus Pinus. 相似文献
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The identification of the conventionally accepted species of Clavulina (Cantharellales, Basidiomycota) in Europe (Clavulina amethystina, Clavulina cinerea, Clavulina cristata, and Clavulina rugosa) is often difficult and many specimens are not straightforwardly assignable to any of those four species, which is why some authors have questioned their identity. In order to assess the status of those species, a morphological examination was combined with the molecular analysis of the ITS region. The same six major clades were obtained in the Bayesian and parsimony phylogenetic analyses, and all six clades were well-supported at least by one of the analyses. Morphological characters, such as the overall branching pattern, the presence and intensity of grey colour, the cristation of the apices, and basidiospore size and shape were to various extents correlated with the phylogenetic signal obtained from the ITS region. The congruence between the molecular analyses and morphology, rather than geographical origin, suggests the existence of several species that can be delimited using a combined phylogenetic and morphological species recognition. The analyses revealed that C. cristata and C. rugosa are well-delimited species. In contrast, more than one taxa could be subsumed under the names C. amethystina and C. cinerea, the taxonomical complexity of which is discussed. The ITS region is proved to be adequate to separate phylogenetic species of Clavulina. 相似文献
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Teresa Nogueira M.J. Marcelo-Curto A. Cristina Figueiredo José G. Barroso Luis G. Pedro Patrizia Rubiolo Carlo Bicchi 《Biochemical Systematics and Ecology》2008
The geographical distribution and analysis of the essential oils of species from three sections of Hypericum L. (Guttiferae/Clusiaceae/Hypericaceae) from Portugal are presented. Hypericum perfoliatum (section Drosocarpium) grows wild in the centre and south of Portugal; Hypericum humifusum and Hypericum linarifolium are both from section Oligostema, the former occurring throughout the country, while the second is distributed mainly in the north and centre; Hypericum pulchrum (section Taeniocarpium) is confined to the littoral north of Portugal. The essential oils were obtained by distillation–extraction, hydrodistillation and distillation in a modified Marcusson apparatus from the dried aerial parts of the different populations and were analysed by GC and GC–MS. Monoterpene hydrocarbons constituted the main fraction in all oils (43–69%, 53–85%, 28–45% and 48–65% for H. perfoliatum, H. humifusum, H. linarifolium and H. pulchrum, respectively). Sesquiterpene hydrocarbons (2–13%, 6–18%, 21–27% and 16–18%, respectively) and a third fraction of non-terpenic compounds (20–29%, 3–16%, 2–14% and 5–11%, respectively) from the four species attained relatively high amounts in all oils. Within each species, no major differences were detected in the essential oil composition, despite the fact that different locations, phenological phases and extraction methodologies were used. Notwithstanding the dominance of α-pinene in all four species' oils, cluster and principal components analysis on the identified components showed that the range of α-pinene, β-pinene and n-nonane supported a separation of the four species. The essential oil composition of the four species showed some qualitative resemblances, which correlate well with the taxonomical classification based on morphological characters. 相似文献
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The sixty new taxa described in Musci Indici are reviewed. As a result of validation of 54 of these by plates alone, authorities, original specimens and provenance of many have been widely misinterpreted. Evidence from published material, unpublished correspondence and herbarium material demonstrates that W. H. Harvey (1836) is the sole validating author of most of the names; three were validated by J. D. Hooker in 1837, and two names jointly by J. D. Hooker and Harvey in 1840. None was validated by W. J. Hooker, in the past often considered to be the author of some of the names. It is shown that Musci Indici names should be typified by lectotypes; recent typifications of four of the names by ‘holotypes’ and six out of eight published ‘lectotypes’ are untenable as the specimens selected were not original material studied by Harvey, and should be superseded by new lectotypes. Five specimens are selected as new lectotypes. Original material, mostly in Harvey's herbarium in TCD, is identified as most suitable for future lectotypification of the other names. Types for the three names based solely on Royle material are located in LIV and BM. Original Harvey material is also preserved in GL, but most of the Wallich collections in BM, E and elsewhere are not part of the original material. For Neckera blanda no suitable type specimen was located; the original published plate is selected as lectotype with a specimen in BM as a supporting ‘epitype’. Many of the original localities published in 1840 as ‘Nepal’ are shown to be erroneous. As far as possible these are corrected but for some taxa provenance remains doubtful. Twenty-two of the new names are shown not to have been based on material from Nepal; as a result ten species (Acanthorrhynchium papillatum, Brachythecium kamounense, Chaetomitriopsis glaucocarpa, Meiothecium microcarpum, Mitthyridium repens, Rozea fulva, Splachnobryum flaccidum, Sterophyllum radiculosum, Trichosteleum boschii and Trismegistia lancifolia) and Trismegistia lancifolia) are deleted from the Nepal checklist. Twenty-eight of the new species are considered to be reliably based on material from Nepal, and a further five doubtfully so. Rozea microcarpa Broth. is shown to be an synonym of R. fulva (Harv.) M. Fleisch. Past taxonomic confusion between Hypnum cordatum Harv. and Neckera cordata [Hook. ex] Harv. is untangled; the first is shown to be a synonym of Eurhynchium hians (Hedw.) Sande Lac. and the second is the basionym of Penzigiella cordata (Harv.) M. Fleisch. 相似文献
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Marta D. Mendes Helena Trindade A. Cristina Figueiredo José G. Barroso Susana S. Fontinha Luis G. Pedro 《Biochemical Systematics and Ecology》2009
Chemical and genetic differences of 11 individuals of Angelica lignescens and 3 individuals of Melanoselinum decipiens were studied to determine whether volatile components could be used as taxonomical markers and to examine the correlation between molecular and chemical markers. The volatiles were isolated from each individual by distillation–extraction and analyzed by gas chromatography (GC) and gas chromatography–mass spectrometry (GC–MS). The same plants were analyzed by Inter Simple Sequence Repeat (ISSR) using 14 arbitrary primers. The main component of volatile fraction isolated from vegetative aerial parts of A. lignescens was limonene (57–86%) while in M. decipiens the main components detected were β-pinene (38–47%) and sabinene (1–33%). Cluster analyses based both on the chemical composition of volatile fraction and on molecular markers grouped the 14 accessions in two main groups, corresponding to each of the two species under study. Considering the species together, a moderate Pearson's correlation of r = 0.61 was obtained between the two analyses. 相似文献
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Ann Budd Foster 《Journal of experimental marine biology and ecology》1979,39(1):25-54
Mature colonies of Montastraea annularis (Ellis & Solander) and Siderastrea siderea (Ellis & Solander) were transplanted reciprocally between four reef environments near Discovery Bay, Jamaica. Multivariate analyses of variables describing corallite structures show that colonies of M. annularis change their skeletal morphology after transplantation from that characteristic of their original habitat to that characteristic of the environment to which they were moved. Control colonies of M. annularis, however, retain the morphology characteristic of their original habitat after manipulation. Many colonies of S. siderea similarly altered their morphology after transplantation, but some retained the morphology characteristic of their original habitat. Most control colonies of S. siderea did not change after manipulation. In general, control colonies of S. siderea show more morphologic variation between skeleton deposited before and after manipulation within colonies and also between colonies within populations, than did control colonies of M. annularis.These results indicate that, although M. annularis shows more plasticity than S. siderea. both species have highly plastic phenotypes. A large number of characters describing the architecture of corallites respond to environmental factors such as light intensity, sedimentation rate, water activity, and food availability. The most plastic characters in M. annularis describe coenosteal features and the thickness of thecae. The most plastic characters in S. siderea describe the thicknesses of thecae. septa, and columellae.This study suggests that phenotypic plasticity is an important species attribute in scieractinians and may be a significant mechanism in controlling the distribution and abundance of scleractinians on reefs. 相似文献
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Three new species of the genus Trachyandra are described, T. hantamensis Boatwr. & J.C.Manning, T. kamiesbergensis Boatwr. & J.C.Manning and T. sanguinorhiza Boatwr. & J.C.Manning. These species form part of a group of morphologically similar species referred to here as the T. thyrsoidea group and are distinguished by their generally small stature, filiform leaves (except for T. tortilis), and simple or shortly branched racemes of patent flowers with maculate tepals. Many of the species in the group have roots that contain abundant anthraquinones, visible as a red substance below the outer skin of the roots, and which is soluble in alcohol, thus often staining herbarium papers purple. A synopsis of the eight species that comprise the T. thyrsoidea group is presented, with maps of each species and illustrations of those described as new. 相似文献
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The siliceous valves from species of Tetracyclus (Bacillariophyceae) have variable but characteristic shapes. In this paper, species characterised by having valves with a central constriction are discussed. This distinctive shape occurs during only a period of its lifecycle. Tetracyclus constrictus and Tetracyclus celatom have been applied to fossil specimens occurring in deposits from the west coast of the USA and the east coast of Russia. Do these names apply to two closely related species or are they one and the same taxon? Two further species, Tetracyclus javanicus and Tetracyclus peragalli, have been involved in the identity of T. constrictus–T. celatom. T. constrictus M. Peragallo is the correct name and author for specimens of the extinct Miocene, circum-Pacific (or northern) fossil species with valves panduriform with rounded poles; T. javanicus refers to a species found living on Java only; fossil specimens usually referred to T. javanicus (Java) belong to a new taxon, Tetracyclus bradburyii (USA); T. peragalli is an extinct Miocene fossil, with a northern hemisphere distribution; small (≤10 μm) circular/elliptical fossil specimens, found alongside other specimens, are difficult (if not impossible) to determine to species level. 相似文献
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中国东北辽宁省西部几种中生代化石木 总被引:5,自引:0,他引:5
段淑英 《Acta Botanica Sinica》2000,42(2):207-213
对产自辽宁省西部中生代化石木进行了解剖学研究。经鉴定,它们是:朝阳原始云杉型木(新种)(Protopiceoxylon chaoyangense Duan sp.nov.),西部南洋杉型木(Araucarioxylon sidugawaense Shimakura),巴图南洋杉型木(新种)(Araucarioxylon batuense Duan sp.nov.)和辽西紫杉型木(新种)(Taxox 相似文献
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Mariola Pa?ciak Patricia Sanchez-Carballo Anna Duda-Madej Andrzej Gamian 《Carbohydrate research》2010,345(10):1497-1503
Arthrobacter is a genus of Gram-positive bacteria widely distributed in soil. The ability to catabolize a variety of xenobiotics has shown their potential as a detoxifying agent. Recently, Arthrobacter has been also recognized as an opportunistic pathogen. Glycolipids from A. scleromae, a clinical isolate, and A. globiformis, from soil, were isolated by chloroform-methanol extraction and subsequently purified using column chromatography and high-performance liquid chromatography. Structural studies were carried out utilizing specific chemical degradation, matrix-assisted laser-desorption/ionization Fourier transform ion cyclotron resonance mass spectrometry (MALDI FT ICR-MS), and 1D and 2D nuclear magnetic resonance (NMR) spectroscopy. The major glycolipids in A. scleromae and A. globiformis were found to be a diglycosylglycerol with the structure α-Manp-(1→3)-α-Manp-(1→3)-Gro (Man A-Man B-Gro; G1), and a monoglycosylglycerol with the structure β-Galp-(1→3)-Gro (G2). Glycolipids were acylated at positions 1 of Gro and 6 of Man B in the case of G1 and at positions 1 and 2 of Gro in the case of G2. The distribution of the fatty acids was different in both species. A. scleromae glycolipids contained heptadecanoic acid while in the A. globiformis glycolipids mainly pentadecanoic acid could be detected. The substitution by hexadecanoic acid was proportionally similar in both species. The taxonomical value of major glycolipids from Arthrobacter is also presented. 相似文献
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Joanna Wilbraham 《Journal of bryology》2013,35(2):87-93
New synonymy and distribution records for the genus Macromitrium Brid. in sub-Saharan Africa are presented. Seven names are placed in synonymy, reducing the number of accepted taxa for Macromitrium in sub-Saharan Africa to 33. Macromitrium anomodictyon Cardot was found to be conspecific with M. serpens (Bruch ex Hook. & Grev.) Brid.; M. mauritianum Schwägr. and M. sanctae-mariae Renauld & Cardot are placed in synonymy with M. subtortum (Hook. & Grev.) Schwägr. and M. belangeri Müll.Hal., M. seriatum Paris & Broth., M. bequaertii Thér. & Naveau and M. trollii Dixon in Herz. are all placed in synonymy with M. sulcatum (Hook.) Brid. subsp. sulcatum. The precise lectotypification is implemented for six species within the genus. Macromitrium chloromitrium (Besch.) Wilbraham and M. orthostichum Nees ex Schwägr. are reported new to Tanzania and M. chloromitrium new to continental Africa. 相似文献
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Audrey Rohfritsch Claude Payri Valérie Stiger François Bonhomme 《Biochemical Systematics and Ecology》2007
We employed four markers (two chloroplastic, one mitochondrial and one nuclear) to investigate whether Turbinaria ornata and Turbinaria conoides, two morphologically similar brown algae, are distinct species. The molecular data revealed reciprocal monophyly, thus confirming the two algae as discrete species. Nevertheless, taxonomical ambiguities remain. T. conoides is more morphologically variable than T. ornata. We identified an atypical T. conoides morphotype whose blade possesses intramarginal teeth, a morphological characteristic of the T. ornata group that is normally absent within T. conoides. The molecular data indicate, nonetheless, that this morphotype belongs genetically to the T. conoides group. Thus, the results cast doubt upon the validity of using intramarginal teeth for species diagnosis. 相似文献
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《Cryptogamie Algologie ☆》2001,22(3):297-304
Six species of benthic marine Chlorophyta and Phaeophyceae are recorded for the first time from the coast of Namibia: Ectocarpus fasciculatus Harvey, Feldmannia irregularis (Kützing) G. Hamel, Bachelotia antillarum (Grunow) Gerloff, Straguloria clavata (Harvey in Hooker) Hamel, Entocladia leptochaete (Huber) Burrows and Ulvella lens P. Crouan & H. Crouan. Data concerning local and world distribution of these species as well as some taxonomical remarks are provided. 相似文献
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Neozygites floridana (Weiser & Muma) (Zygomycetes: Entomophthorales) has been reported infecting naturally at least 18 species of tetranychids worldwide. However, the host range of N. floridana is unknown. Epizootics caused by this pathogen to tetranychid populations indicate that N. floridana has the potential to be used as a biological control agent. However, the virulence and specificity of species and strains of Neozygites need to be assessed in the laboratory to reveal its potential as a biological control agent. N. floridana isolates are currently been investigated in Brazil as biological control agents against the tomato red mite, Tetranychus evansi Baker & Pritchard, and the two-spotted spider mite, Tetranychus urticae Koch. The pathogenicity of five strains of N. floridana obtained from T. urticae, T. evansi and T. ludeni Zacher was assessed against populations of Mononychellus tanajoa (Bondar), Schizotetranychus sacharum Flechtmann & Baker, Tetranychus abacae Baker & Pritchard and Tetranychus armipenis Flechtmann & Baker, in addition to the species from which the fungus was obtained. Mummified mites were placed on leaf discs of the host plant of each tetranychid to promote fungal sporulation, and after 24 h the mites were transferred to the leaf discs. Contamination, infection and mummification were evaluated daily for seven days after confinement. Each isolate was pathogenic to three or four out of the six spider mite species tested. However, except for isolate ESALQ1421, all isolates caused higher levels of infection and significant mummification only to the tetranychid species from which they were collected. None of the isolates was pathogenic to S. sacharum and only one isolate infected T. abacae. Alternative hosts may be important for N. floridana survival in tropical regions where resting spores are rarely found. 相似文献