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971.
The genus Psednotrichia (Asteraceae–Senecioneae) is endemic to Angola and currently consists of two annual species, P. xyridopsis (O. Hoffm.) Anderb. & P. O. Karis, and P. newtonii (O. Hoffm.) Anderb. & P. O. Karis. A perennial member of the genus was collected on a recent field trip to Angola, and is here described as P. perennis N. G. Bergh & B. Nord., sp. nov. A key to the three species is provided. 相似文献
972.
The new species Caesia sabulosa Boatwr. and J.C.Manning from deep sands along the West Coast of South Africa and sandy flats in the Cederberg and Bokkeveld Escarpment is described. It is distinguished by its extensively branched rhizome resulting in a robust, clump-forming habit, and unique ‘palisade’ root system of closely packed, hard, vertical roots; mostly larger flowers; erect fruiting pedicels; and details of the seed testa sculpturing. 相似文献
973.
Palystes kreutzmannisp. n. is described from habitats close to Kleinmond, in the Western Cape Province, South Africa. Spiders of this new species live in the typical fynbos vegetation of the Western Cape region. They build retreats between apical leaves of Leucadendron bushes. The systematic position of Palystes kreutzmannisp. n. is discussed. Male and female show characters of different species groups, especially the female copulatory organ seems to be unique within the genus Palystes L. Koch, 1875. 相似文献
974.
Nineteen holotype specimens of the genus Torrubiella described by Dr. Yosio Kobayasi and Mr. Daisuke Shimizu were relocated and accession numbers (TNS-F number) were given. A
new scientific name, Torrubiella plana Hiroki Sato, Ban, Masuya & Hosoya nom. nov. (TNS-F-12061), was proposed for T. minutissima Kobaysi & Shimizu (homonym of T. minutissima Lagarde). The other 18 species follow: T. alboglobosa (TNS-F-12067), T. aurantia (TNS-F-12069), T. corniformis (TNS-F-12064), T. ellipsoidea (TNS-F-12055), T. formosana (TNS-F-12059), T. fusiformis (TNS-F-234548), T. globosostipitata (TNS-F-12057), T. longissima (TNS-F-12071), T. mammillata (TNS-F-12060), T. miyagiana (TNS-F-12062), T. neofusiformis (TNS-F-12058), T. oblonga (TNS-F-12070), T. ooaniensis (TNS-F-12063), T. pallida (TNS-F-12789), T. rosea (TNS-F-12065), T. ryogamimontana (TNS-F-12058), T. ryukyuensis (TNS-F-11932), and T. superficialis (TNS-F-12072). 相似文献
975.
Martin Fikáček 《Biologia》2006,61(2):149-157
Pachysternum loxodonta sp. n. from the Republic of the Congo and Pachysternum sulawesicum sp.n. from Sulawesi Island, Indonesia are described. The generic status of Pachysternum sculpticolle (Régimbart, 1907) is revised, the species is transferred to the genus Cyrtonion and its differences from C. ghanense Hansen, 1989 are discussed. Taxonomy of Pachysternum is discussed, dividing the genus prelusively into three species groups, one comprising all known Oriental and Eastern Palearctic
species, and two comprising the Afrotropical species. Species with unclear positions within the genus Pachysternum or with questionable generic status are left as “Species incertae sedis”. 相似文献
976.
异常球菌属的分类及应用研究进展 总被引:2,自引:0,他引:2
异常球菌属的菌株是一类对引起细胞致死效应的辐射有极强抵抗能力的细菌,这类菌株不形成内生孢子,细胞呈球形或杆状,不具运动性。1956年,Anderson从经过射线灭菌处理后的肉罐头中发现了第一个异常球菌属的菌株(Deinococcus radiodurans)R1,该菌已得到了较为广泛的研究,以期阐明其抗辐射机制。伴随着微生物分类技术的发展,异常球菌属菌株的分类地位经历了很大的变化。目前,该属已涵盖了20个有效发表种。也由于异常球菌属菌株耐受辐射的能力是大肠杆菌忍耐辐射能力的千倍之上,而使其应用研究受到了广泛关注。 相似文献
977.
Sebastian Klaus Christoph D. Schubart Dirk Brandis 《Organisms Diversity & Evolution》2006,6(3):199-217
Phylogenetic relationships of gecarcinucoid freshwater crabs were investigated, based on morphology of the male second gonopod. In addition, a comparison of sequences from the mitochondrial large subunit rRNA gene helped to resolve the phylogeny of this group and relationships to other Old World freshwater crabs. As a result, we recognise two sister groups within the Gecarcinucoidea, the African Deckeniidae and the Asian Gecarcinucidae. Deckeniidae includes three monophyletic clades, the Deckeniinae in East Africa and on the Seychelles, the West African Globonautinae and the Malagasy Hydrothelphusinae. Gecarcinucidae comprises two sister groups, the Gecarcinucinae with representatives in Sri Lanka, India and southeast Asia, and the Parathelphusinae in India, southeast Asia, the Sundaic Islands and Australia. Interpretation of our phylogenetic results leads us to propose a new biogeographic hypothesis for the Gecarcinucoidea. Most likely, the gecarcinucoid freshwater crabs have an African origin; their distribution can be explained by successive events of dispersal. This model can be correlated with palaeogeographical and palaeoclimatological data for the Cenozoic, suggesting a gecarcinucoid dispersal to Asia via the “Lemurian Stepping-Stones”, a chain of islands in the West-Indian Ocean that were emergent in times of low sea levels during the Oligocene. 相似文献
978.
Melampsora nujiangensis, a rust fungus found on Populus yunnanensis in China, is described as a new species. Light and scanning electron microscopy with herbarium specimens of the rust fungus
show that the shape of its urediniospores differs from that of other known species of Melampsora, and its urediniospore walls are thinner than the other species. Furthermore, in phylogenetic trees based on the DNA sequences
(28S and ITS) the rust fungus is phylogenetically separated by high bootstrap values. These results indicate that the fungus
is an isolated species among the genus Melampsora.
Contribution no. 202 from the Laboratory of Plant Parasitic Mycology, Graduate School of Life and Environmental Sciences,
University of Tsukuba, Japan 相似文献
979.
G. Landeras M. Alfonso N. M. Pasiecznik P. J. C. Harris L. Ramírez 《Biodiversity and Conservation》2006,15(5):1829-1844
There has been much taxonomic confusion over the identification of Prosopis species, especially where introduced. Prosopis juliflora is the most widespread species in the arid and semi-arid tropics, although it has been confused with other species, particularly
the closely related Prosopis pallida. In this study, RAPDs markers were used for the first time to distinguish between these species. Eighteen primers were used
in amplification reactions, which yielded an average of 120 bands per accession. A dendrogram showing genetic similarities
among accessions was constructed using UPGMA cluster analysis and the Nei and Li similarity coefficient. The genetic similarity
observed between P. juliflora and P. pallida is similar to the value in sympatric Prosopis species in North America, and reconsideration of the series rank in section Algarobia is suggested. Species-specific markers
confirmed that material in Burkina Faso is P. juliflora, but suggested that material collected in Brazil, Cape Verde and Senegal is P. pallida, whereas this has previously been identified as P. juliflora. 相似文献
980.
Angela Schmitz-Ornés 《Journal of Ornithology》2006,147(3):495-503
I propose a methodology to obtain and compare integral information on bird plumage coloration, using colour spectral data to conduct studies on geographic variation and taxonomy of different bird groups. I used principal component analysis and discriminant function analysis to compare groups of individuals by plumage coloration. As examples of the application of the methodology, I compared populations within the genus Eulampis and Anthracothorax. The results indicate possible taxonomic inadequacies and reveal situations that deserve further analysis, demonstrating the potential of the methodology in this area.Electronic Supplementary Material Supplementary material is available for this article at and is accessible for authorized users. 相似文献