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951.
952.
《Mycoscience》2014,55(6):456-461
Two new species, Melanoleuca leucopoda and M. porphyropoda, are described based on collections made from Shenyang City, Liaoning Province, China. Melanoleuca leucopoda is mainly characterized by its whitish stipe with fibrils and oblong spores with elongated warts. Melanoleuca porphyropoda differs from all other Melanoleuca species in lacking cystidia and in having decurrent gills and a purplish stipe. The sequences of internal transcribed spacer regions (ITS1-5.8S-ITS2) of Melanoleuca species were analyzed and the results indicated that two new species clustered into two clades and differed from the other species of the genus. The combination of morphological and molecular data confirmed that the two fungi are new species. The morphological similarity of the new species to other species of Melanoleuca and the systematic position of the two species based on molecular data are also discussed. 相似文献
953.
Swen C. Renner Pamela C. Rasmussen John H. Rappole Thein Aung Myint Aung 《Journal of Ornithology》2009,150(3):671-683
The little-known taxon Cyornis [banyumas] magnirostris has long been treated as a race of the widespread Hill Blue Flycatcher C. banyumas, with which it was thought to be allopatric during the breeding season. On the basis of morphology, magnirostris has lately been considered a full species, endemic as a breeder to northeastern India. Our recent field work during migration
and the breeding season (September 2005 and June–July 2006) has, however, resulted in the first records of magnirostris from northern Burma/Myanmar, establishing that its breeding range broadly overlaps the range of C. banyumas
whitei. We demonstrate how historical factors, sources of error, including fraud, errors of omission and commission, and inferences
based on lack of data have all negatively affected assessment of species limits and conservation status in this speciose group
of flycatchers. We also provide evidence that the taxon C. [banyumas] lemprieri is highly distinct and should be treated as a full species. 相似文献
954.
通过对本属48个分类群的检查,发现女贞属的种子有4种类型:1)小球形,2)卵形,3)椭圆形,4)具沟形,并且它们与果实的类型有密切的相关性。因此,以种子的形态以及内果皮的类型为主要分组依据,提出了一个新的分类系统。此外,本文将L.xingrenense作为L.nepalense的地理亚种处理;将L.longipedicellatum和L.yunguiense归并到L.lianum;将L.longitubum及L.robustum subsp.chinense分别归并到L.leucanthum及L.expensum。真正的粗壮女贞L.robustum分布于斯里兰卡、印度及缅甸等地,未见于我国,文献上所载产于我国的粗壮女贞均为L.expansum的错误鉴定。 相似文献
955.
A new species, Strobilomyces verruculosus, is described and illustrated. It is morphologically distinct from other species of Strobilomyces by having a verruculose pileus with small subpyramidal scales, a long and thick stipe with small warty to appressed scales,
subdecurrent tubes, and incompletely reticulate basidiospores. Molecular phylogenetic analyses using the mitochondrial cytochrome
oxidase subunit 3 (cox3) gene support that it belongs to the genus Strobilomyces and is highly differentiated from the other members of this genus found in Japan. 相似文献
956.
The taxonomy of the order Zoantharia (=Zoanthidea=Zoanthiniaria) is greatly hampered by the paucity of diagnostic morphological features. To facilitate discrimination between similar zoanthids, a combination of morphological and molecular analyses is applied here. The three most abundant zoanthid species in shallow waters of the southern Chilean fjord region are described. Comparison with other zoanthids using molecular markers reveals that two of them are new to science; these are described as Mesozoanthus fossii gen. n., sp. n. and Epizoanthus fiordicus sp. n. Their representatives grow on rocky substratum and do not live in symbiosis with demosponges. In the less abundant M. fossii, animals are greyish in colour and resemble members of Parazoanthus in growth form. Individual polyps can be up to 35 mm long. The more abundant E. fiordicus are also greyish; the polyps arise from thin stolons and reach only 12 mm in length. The third species studied is Parazoanthus elongatus McMurrich, 1904. For these three Chilean zoanthid species, in-situ photographs are presented as well as information on distribution, habitat and associated species. Establishment of the Mesozoanthus gen. n. is of particular importance to taxonomy in the chaotic suborder Macrocnemina. 相似文献
957.
Question: Species diversity is commonly expressed as the number of species present in an area, but this unique value assumes that all species contribute equally to the area's biodiversity. Can taxonomic diversity be used as a complementary measure for species richness in order to assess plant biodiversity in remnants of primary forest and patches of secondary vegetation? Location: Veracruz, Mexico. Methods: Using data from six sampling transects of each vegetation type in an elevation gradient (400‐900 m a.s.l.), we compare the point, mean and cumulative floristic diversity of primary forest and secondary vegetation in a tropical deciduous landscape, using species richness and two measures of taxonomic diversity: average taxonomic distinctness (Δ+) and variation in taxonomic distinctness (Λ+). We performed a randomization test to detect differences in the observed taxonomic diversity, from the expected values derived from the species pool of each vegetation type. Results: We found that the species of secondary vegetation are more closely related at low taxonomic levels (lower Δ+ value) than the species of primary forest remnants. Also, in secondary vegetation the distribution of species is uneven among the taxonomic levels and units (high Λ+ value). These patterns are consistent for point, mean and cumulative taxonomic diversity. Families Asteraceae, Euphorbiaceae, Fabaceae and Poaceae are over‐represented, while families Bromeliaceae, Cactaceae, Orchidaceae and Pteridaceae are under‐represented in secondary vegetation. Conclusions: Although in a previous paper we concluded that secondary vegetation is more alpha‐diverse than primary forest (in terms of both cumulative and mean species richness), and beta‐diversity between vegetation types is notoriously high, we now provide a wider view by highlighting the importance of taxonomic diversity in primary forest remnants. Our data indicate that to measure biodiversity accurately, we should seek to capture its different facets. This will allow us to make conservation recommendations based on a broader view, and not on a single dimension. 相似文献
958.
During a survey of Pythium species in soils of Japan, Pythium isolates growing at high temperatures were obtained from an uncultivated field soil in Wakayama Prefecture. All six isolates
showed similar morphology to each other and had complexly branched secondary hyphae, globose nonproliferating sporangia, and
smooth-surfaced oogonia that have one or two oospores per oogonium. The combination of these characteristics differentiated
these isolates from other Pythium species reported. Phylogenetic analyses based on sequences of the ribosomal DNA ITS and D1/D2 region of the large subunit
showed that all Pythium isolates were clustered in a single clade that was distantly related to other known clades of the genus. We described these
isolates as a new Pythium species, Pythium apinafurcum, based on morphology and molecular phylogeny. The P. apinafurcum isolates nonsymptomatically infected the roots of seedlings of bermudagrass, cabbage, and cucumber in a pot inoculation test. 相似文献
959.
The new species, Annesorhiza calcicola Magee and J.C. Manning, is described. It is known only from a few limestone outcrops around Jacobsbaai on the Saldanha Peninsula on the West Coast of South Africa. The species differs from all others in the genus in its small stature (inflorescence less than 0.3 m and leaves less than 150 mm long), the hysteranthous, pilose leaves which are completely absent at flowering (in the other species dead or dying at flowering and usually glabrous), the greyish-black, pilose inflorescence (yellowish-brown and glabrous in the other species) and the smaller homomericarpic fruit less than 5 mm long. 相似文献
960.
Two new species of Asteraceae (tribe Anthemideae, subtribe Pentziinae) from the Cape Floristic Region of South Africa are described. Marasmodes schlechteri Magee & J.C.Manning, a local endemic from the lowlands between Piketberg and the Olifants River Mountains, is distinguished by its spreading leaves with axillary fascicles and relatively large, solitary capitula with obconical involucre borne on very short lateral shoots. Pentzia trifida Schltr. ex. Magee & J.C.Manning is a well-collected limestone fynbos endemic that is readily distinguished by the regularly trifid leaves, broadly cyathiform involucres with lanceolate to oblanceolate bracts, and the well developed pappus extending the entire length of the relatively short corolla tube. 相似文献