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1.
We describe two new species of Phrynopus from cloud forests in Cochabamba, Bolivia. The new species are assigned to the P. peruanus group and are characterized by the presence of basal webbing, distinctive coloration, and by having the first finger shorter than the second. The first of these new species was collected near Montepunko in Parque Nacional Carrasco and is known from eight males and six females. Among its distinctive characteristics are round cream-colored glands on its flanks. A second species is known from one male and one female collected near "Zona de Aguirre" near the northwest border of the park. V and X-shaped blotches and a dorsum that is smooth except for dorsolateral and scapular folds characterize this species. Musculature has rarely been described for species of Phrynopus. The species from Montepunko has unusual gular and thigh musculature that is quite unlike other species of the genus.  相似文献   

2.
Aims: The famous traditional Chinese Maotai-flavour liquor is produced by a unique spontaneous simultaneous saccharification and fermentation process, which contributes to a distinctive yeast community with specific physiological properties and performances. Therefore, it would be useful to investigate this yeast community and reveal the novelty of its characteristics. Methods and Results: Nine yeast species were obtained from the fermentation period. A combination of physiological and functional analyses revealed a very high diversity of yeast populations. In particular, the extremely high temperature and low acidity of the fermentation conditions led to an accumulation of species with distinctive heat- and acid-resistant properties. Moreover, these yeast species were also significant flavour contributors, for various alcohols, acids and esters. Conclusions: The Chinese Maotai-flavour liquor-fermentation process is rich in yeast resources with distinctive fermentation properties, which were different from other beverages. Significance and Impact of the Study: This work is the first to study the complex yeast ecology of the Maotai-flavour liquor-making process. It allows a deeper insight into the mechanism of this process.  相似文献   

3.
The geographical variation of three qualitative plumage characters and three body measurements of populations of the Scaled Woodcreeper (Lepidocolaptes squamatus), a species whose range is centered in eastern Brazil, is analyzed. Three distinctive populations are recognized (wagleri, squamatus, and falcinellus). Under the biological species concept (BSC), two species are recognized (L. squamatus, including squamatus and wagleri as subspecies; and L. falcinellus). Under either the phylogenetic species concept (PSC) or under the evolutionary species concept (ESC), the three distinctive populations should be regarded as independent species. Based on plumage similarities, we suggest that squamatus and wagleri form a monophyletic group, with falcinellus as its sister-group. Geological changes (tectonism and formation of river courses) are suggested as causal factors that promoted speciation in Scaled Woodcreepers.  相似文献   

4.
新疆地衣资源多样性研究进展   总被引:4,自引:2,他引:2  
在生物多样性中,地衣是一类独特的生物。新疆地衣资源丰富,至今在新疆已定名的地衣有398种,隶属于98属;包括不完全真菌类地衣4属4、种。深入了解新疆地衣物种多样性和其生态环境及地衣的应用价值,有利于合理利用新疆的生物资源,有效保护生态环境。  相似文献   

5.
Johnson NK  Cicero C 《Molecular ecology》2002,11(10):2065-2081
Avian genera characterized by sibling species with distinctive habitat preferences present an evolutionary enigma in view of the more commonplace occurrence of syntopic congeners that differ strikingly in colour and pattern. No existing theory has explained the evolutionary background that led to these differences. Here we propose that great phenotypic similarity among some groups of sibling species limits their coexistence and that clues to their radiation can be seen in patterns of geographical occurrence. To illustrate our thesis we focused on the New World flycatcher genus Empidonax, a group of 15 species notorious for their great phenotypic similarity. Using 3069 base pairs of mitochondrial DNA from four genes, we produced a complete molecular phylogeny that identified four clades, three of which represent close relatives. The fourth clade includes only E. virescens, which apparently has no close living relatives. The majority of species, including many distant relatives, are completely (58.1%) or essentially (6.7%) allopatric in breeding distribution and exhibit striking ecological segregation into distinctive climate-vegetation zones. Even where ranges overlap, occupancy of the same habitat by different species is rare. Phylogenetic and distributional patterns in Empidonax suggest a peripatric model of stepwise colonization and then range expansion of small groups of pioneers during glacial periods into initially enlarging, distinctive habitats destined to be widespread during interglacials. Vicariance is not indicated in the absence of barriers of appropriate age and geographical position. Rapoport's rule that northern species have larger ranges than southern species is strongly supported.  相似文献   

6.
7.
The Australian xiphydriid woodwasp genus Austrocyrta , previously known only from a single species, A. australiensis Riek, is revised. A second distinctive species from Carnarvon National Park in south-central Queensland, A. fasciculata Jennings & Austin, sp. nov., is described, and a key to separate the males of the two species is provided.  相似文献   

8.
Adults of 4 of the 6 species constituting the subgenus Carios and of 3 of the 4 species constituting the subgenus Chiropterargas were studied by scanning electron microscopy. All species parasitize Old World cave-dwelling insectivorous bats (Microchiroptera). The anterior pit setae number 10 in Carios and 10 or 11 in Chiropterargas. In most Carios, the setiform seta is replaced by a second serrate seta. In 2 of the 3 studied Chiropterargas species, 1 of the 2 grooved setae is exceptionally long. Porose setae number 3 in Carios and 3 or 4 in Chiropterargas. The Haller's organ roof in both subgenera is solid, lacking perforations; the aperture is narrowly transverse in Carios, irregularly wide or wide and transverse in Chiropterargas; uniquely, 1 or 2 sensilla protrude from the aperture of Chiropterargas species. The protruding sensilla and long grooved seta of Chiropterargas suggest a probably distinctive sensory-behavior pattern common to these ticks. Other morphological characters are discussed and compared to show relationships between these 2 subgenera and the subgenera Argas and Persicargas and distinctive characters present only in adult and/or larval Carios and Chiropterargas.  相似文献   

9.
Specimens of Pintneriella musculicola Yamaguti, 1934 are redescribed based on paratype material and specimens subsequently allocated to the species by its describer. The cestode species is characterised by two bothridia, a typical heteroacanthous armature with a distinctive basal swelling and basal armature, a space between hook files 1 and 1', nine hooks per principal row, no intercalary hooks and bands of hooklets or chainettes but a distinctive space on the external surface of the tentacle between hook files 9 and 9'. The strobilia is unknown. The features described indicate that Pintneriella is a valid genus within the Heteracanthoidea. Its currently known morphological features do not allow its allocation to an existing family.  相似文献   

10.
本文应用聚丙烯酰胺凝胶电泳方法分析了瓢虫科2属5种的酯酶同工酶(EST),结果显示属间的酶谱有显著差别,在属内具有某些共性。每个种都具有自己特有的谱型,彼此易于区分。聚类分析表明同种不同个体有差异,但小于性别差异,种间差异明显大于性别差异。聚类分析还显示5个种亲缘关系的远近,与形态分类结果一致。  相似文献   

11.
Recent work has suggested that in temperate and subtropical trees, leaf surface bacterial communities are distinctive to each individual tree species and dominated by Alpha- and Gammaproteobacteria. In order to understand how general this pattern is, we studied the phyllosphere bacterial community on leaves of six species of tropical trees at a rainforest arboretum in Malaysia. This represents the first detailed study of ‘true’ tropical lowland tree phyllosphere communities. Leaf surface DNA was extracted and pyrosequenced targeting the V1–V3 region of 16S rRNA gene. As was previously found in temperate and subtropical trees, each tree species had a distinctive bacterial community on its leaves, clustering separately from other tree species in an ordination analysis. Bacterial communities in the phyllosphere were unique to plant leaves in that very few operational taxonomic units (0.5%) co-occurred in the surrounding soil environment. A novel and distinctive aspect of tropical phyllosphere communities is that Acidobacteria were one of the most abundant phyla across all samples (on average, 17%), a pattern not previously recognized. Sequences belonging to Acidobacteria were classified into subgroups 1–6 among known 24 subdivisions, and subgroup 1 (84%) was the most abundant group, followed by subgroup 3 (15%). The high abundance of Acidobacteria on leaves of tropical trees indicates that there is a strong relationship between host plants and Acidobacteria in tropical rain forest, which needs to be investigated further. The similarity of phyllosphere bacterial communities amongst the tree species sampled shows a significant tendency to follow host plant phylogeny, with more similar communities on more closely related hosts.  相似文献   

12.
A new species, Ferulugo iduea , Özhatay et Akalin from Bahkesir, Kaz Da (Mount Ida) in north-west Turkey is described. The distinctive characteristics of the new species, and its relationship with three other endemic species ( F. humilis, F. macrosciadia and F. sandrasica ) are discussed.  相似文献   

13.
14.
《Palaeoworld》2022,31(3):478-484
Paleopalynology evidence and megafossil records indicated that tree fern order Cyatheales, played an important role in Mesozoic terrestrial ecosystem. Few fossil records of the family Thyrsopteridaceae have been reported so far. In the present study, we describe a distinctive fertile pinnule segment of a fern plant preserved in a mid-Cretaceous amber from Myanmar. The well-preserved fertile pinnule is identified as a new species of the extant tree fern genus Thyrsopteris (Thyrsopteridaceae): Thyrsopteris cyathindusia n. sp. It represents the second fossil species of Thyrsopteridaceae found in the mid-Cretaceous amber from Myanmar. The new species shows distinctive characteristics of the sporophyll that are considered paleoecologically/paleobiogeographically significant for evolution of the Thyrsopteridaceae.  相似文献   

15.
Pollen morphology was examined in 40 samples from 19 species in the genus Erythronium (Liliaceae) using scanning (SEM) and transmission electron microscopy (TEM). Pollen grains are monosulcate monads, except for a plant of E. oregonum which has dyad grains. North American and European species are characterized by reticulate exine sculpture composed of various degrees of wavy muri and variably-sized lumina. The most distinctive feature of exine sculpture in the genus is exhibited by the Asian species E. japonicum, which has a unique reticulate pattern composed of striate muri and a distinctive exine structure without columellae. The distinctness of E. japonicum pollen suggests that it has specialized in isolation from species in North America and Europe.  相似文献   

16.
Satellite imagery as a tool for monitoring species diversity: an assessment   总被引:11,自引:1,他引:10  
1. A landscape of 5 × 5·5 km in the Karnataka region of the Western Ghats of India was mapped into seven landscape element types, using field identification of types as well as supervised and unsupervised classification of satellite imagery.
2. Plant communities distributed in these landscape element types were surveyed in the field using 246 quadrats of 10 × 10 m, in order to assess whether these types could be distinguished in terms of species composition. All angiosperms excluding grasses, which could not be identified accurately in the field, were recorded for this purpose.
3. Landscape element types identified in the field harboured significantly distinctive sets of species of flowering plants, and were also by and large distinctive in terms of their species richness.
4. Landscape element types could be identified accurately on the basis of supervised classification: the types thus demarcated harboured distinctive sets of flowering plants.
5. Landscape element types coupled to satellite imagery could then be used to organize a programme of monitoring biodiversity.
6. Unsupervised classification of satellite imagery did not permit classification of landscape element types with a high enough level of accuracy. In consequence, the demarcated landscape element types did not harbour significantly distinctive sets of species of flowering plants. Unsupervised classification is therefore not appropriate in a programme of monitoring biodiversity.  相似文献   

17.
Comparison of ribosomal and isozymic phylogenies of tetrahymenine ciliates   总被引:2,自引:0,他引:2  
A recent analysis of sequence variations in ribosomal RNA's from 31 species of tetrahymenine ciliates groups them into 9 sets referred to as "ribosets." These species associations are not well correlated with the distributions of distinctive morphological characteristics. The phylogenetic structure suggests that modern "pyriform" tetrahymenines may be paraphyletic survivors of primitive design and that the morphologically distinctive forms may include examples of convergent evolution of derived forms. Alternatively, the common ancestor may have been a polymorphic species that has lost its plasticity in some derived lineages. In an attempt to test the ribosomal phylogeny, we here compare it with a phylogeny based on isozymic variation. The main features of the ribosomal and isozymic phylogenies are similar. The carnivorous (macrostome-forming) species are widely scattered in both, as are the bacteriophagous pyriform species. Isozymic and ribosomal analyses are optimally useful, however, in different contexts. Isozymic variations can distinguish species that are ribosomally identical. Ribosomal variations provide more secure evaluations of distant relationships.  相似文献   

18.
Summary A new marine species of Chrysochromulina, characterized by distinctive spined and spineless scales is described. The value of the new species for the experimental study of haptonema movements is outlined and a brief comparison is made with four other previously named species with spined scales.  相似文献   

19.
A recent analysis of sequence variations in ribosomal RNA's from 31 species of tetrahymenine ciliates groups them into 9 sets referred to as "ribosets." These species associations are not well correlated with the distributions of distinctive morphological characteristics. The phylogenetic structure suggests that modem "pyriform" tetrahymenines may be paraphyletic survivors of primitive design and that the morphologically distinctive forms may include examples of convergent evolution of derived forms. Alternatively, the common ancestor may have been a polymorphic species that has lost its plasticity in some derived lineages. In an attempt to test the ribosomal phylogeny, we here compare it with a phytogeny based on isozymic variation. The main features of the ribosomal and isozymic phylogenies are similar. The carnivorous (macrostome-forming) species are widely scattered in both, as are the bacteriophagous pyriform species. Isozymic and ribosomal analyses are optimally useful, however, in different contexts. Isozymic variations can distinguish species that are ribosomally identical. Ribosomal variations provide more secure evaluations of distant relationships.  相似文献   

20.
Dermal and hypodermal anatomical features of 70 species representing 21 genera of North American Cactoideae were studied. Results show that all species examined have parallelocytic stomata and anticlinal wall surface varies from straight to undulate. Cuticle thickness is mostly narrow (1–10 μm) contrary to the general opinion that cuticle is thick in most cacti; however, few species such as Ariocarpus fissuratus and several species of Pachycereus show a distinctive thick cuticle. More than 80% of the species studied have a single-layered epidermis. Papillae occur in eight species belonging to four genera. Notable papillae are a feature shared by all members of Peniocereus subg. Peniocereus. Other species show a bullate surface produced by irregular patches of secondary epidermal cell divisions. Commonly, the hypodermis is composed of more than two cell layers with distinctive collenchymatous walls as reported in many South American species. Silica bodies, prismatic crystals, druses, sphaerocrystals, and tannins are the most common cellular inclusions that distinguish several genera and appear to have taxonomic value. However, a more thorough search in species of Cephalocereus, Coryphantha, Echinocereus, Mammillaria, Neobuxbaumia, Pilosocereus, and Turbinicarpus is needed to support the previous assertion. Electronic Publication  相似文献   

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