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1.
The mating systems operating in seven species of Marasmius collected recently in northern Thailand were determined. Marasmius cremeus belonging to sect. Sicci subsect. Siccini ser. Leonini, and Marasmius straminiceps belonging to sect. Marasmius subsect. Sicciformes are described as new species. Five members of sect. Marasmius were tetrapolar (bifactorial), viz. M. apatelius, M. guyanensis, M. nigrobrunneus, M. ruforotula, and M. straminiceps. Two members of sect. Sicci were bipolar (unifactorial), viz., M. corneri (syn. M. incarnatus) and M. cremeus. Our data support the hypothesis that the mating system is consistent within infrageneric taxa. The seven species that are herein described, illustrated, and compared with phenetically similar species represent the first reports for this genus in Thailand.  相似文献   

2.
The genus Cyphellophora includes human- and plant-related species from mammal skin and nails, plant materials, and food. On the basis of analysis of ITS, LSU, TUB2 and RPB1 data and morphological characters, three new species, Cyphellophora phyllostachysdis, C. artocarpi and C. musae, associated with sooty blotch and flyspeck disease, were added to this genus. The 2D structure of ITS1 and ITS2 confirmed this taxonomic status. Pathogenicity tests on apple fruit indicated that C. artocarpi could be a sooty blotch and flyspeck pathogen of apple.  相似文献   

3.
Two new species of hyphomycetes,Xenocylindrocladium guianense andX. subverticillatum, are described from plant debris collected in French Guiana and Singapore, respectively. The genusXenocylindrocladium has thus far been known from one species,X. serpens, which was described from plant debris collected in Ecuador. The two new taxa are compared with and distinguished fromX. serpens based on morphology, cultural characteristics and phylogenetic analysis of DNA sequence data of the 5.8S rDNA with flanking ITS1 and ITS2 regions and the 5′ end of the β-tubulin gene. These species are also compared with other closely related hypocrealean taxa. Present collection data suggest that species ofXenocylindrocladium could be restricted to the tropics.  相似文献   

4.
Three genera of lagomorphs, Prolagus, Lagopsis, and “Amphilagus,” were identified during a revision of the lagomorph material from Sandelzhausen (MN5, Early/Middle Miocene boundary, southern Germany). Evidence of two morphological and dimensional classes were observed at some tooth positions in Prolagus (some p3 show an unmistakable P. oeningensis morphology, others closely resemble P. crusafonti), but not at other tooth positions (e.g., M1–2). Insufficient data from Sandelzhausen precludes identification of two different species of Prolagus from this locality, and to define the characteristics of the possible P. crusafonti-like species. Thus, all Prolagus specimens have been classified as P. aff. oeningensis. The genus Lagopsis is represented by L. cf. penai, whose presence is compatible with a MN5 age. The relative abundance of Lagopsis to Prolagus may indicate relatively cool and wet palaeoclimatic conditions. The largest primitive lagomorph species from continental Europe is present at Sandelzhausen. Morphological and dimensional comparisons with other European primitive lagomorphs exclude any affinity with the genera Eurolagus and Titanomys and with the species included in “Amphilagus ulmensis”. Some common features with “Amphilagus antiquus” were observed, although they are not sufficient for the attribution to this taxon. Until there is a general revision of European primitive lagomorphs, the Sandelzhausen giant lagomorph is classified as “Amphilagus” sp. Its origins, whether from evolution within Europe or migration from Asia, remain unknown.   相似文献   

5.
报道了中国云南省兰科(Orchidaceae)兜兰属(Paphiopedilum)一新天然杂交种:哀牢山兜兰(Paphiopedilum×ailaoshanense B. Liu & S. P. Chen)。哀牢山兜兰与白旗兜兰(P. spicerianum)和沧源兜兰(P. gratrixianum var. cangyuanense)近缘,与前者的区别在于哀牢山兜兰花梗和子房有毛,中萼片带紫色晕以及紫色斑点,花瓣上侧暗绿色带紫色晕,下侧黄绿色;与后者的区别在于中萼片具1条宽阔的紫褐色中带,退化雌蕊紫色。哀牢山兜兰与天然杂种泸水兜兰(Paphiopedilum×lushuiense)相似,而哀牢山兜兰的中萼片下部边缘不后卷,近基部具紫红色晕,合萼片具2条明显紫色粗脉,花瓣匙形,上边缘波状,长6.0~6.2 cm,唇瓣长5.0~5.5 cm。为厘清哀牢山兜兰,沧源兜兰及白旗兜兰之间的关系,基于3个叶绿体基因片段(matK、rbcL、trnL),构建了兜兰属部分植物系统发育树。鉴于形态和分子数据,认为哀牢山兜兰是天然杂交种。凭证标本存放于福建农林大学标本馆。  相似文献   

6.
Hänninen  K.  Ohtonen  R.  Huttunen  S. 《Plant and Soil》1999,216(1-2):129-138
Legumes as ground cover are regularly planted to increase nitrogen economy of crops and to improve soil. In the present study various clover species were evaluated as vegetative ground cover in nursery field production of micropropagated red birch (Betula pubescensEhrh. f. rubraUlvinen f. nova) in two 2-year experiments. The clover species and cultivars, Trifolium pratenseL. ‘Bjursele’, T. repens L. ‘Jogeva’, T. repens L. ‘Sonja’, T. hybridum L. ‘Frida’, T. incarnatum L. ‘Opolska’, T. resupinatum L. and T. subterraneum L. were compared to grass sod Festuca rubra L. ‘Ensylva’ and to a coverless ground (control). The last one was kept weed free by hand hoeing. Birch (leaves, stems, branches and roots) and soil nutrient concentrations (N, P, K, Ca, Mg and Fe) were analysed and nutrient ratios in birch determined. The annual clovers, T. incarnatumL., T. resupinatumL. and T. subterraneumL., provided about the same nutrient status in birch as did the control. Perennial clovers and grass were strong competitors with trees. High levels of P and Mg in birch leaves relative to N concentration were typical for poorly growing seedlings. Neither annual nor perennial clovers did generally improve soil nutrient status. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

7.
Lake Huetzalin (Xochimilco) is a shallow waterbody in Mexico City with a dominance of the littoral cladocerans Simocephalus vetulus, Alona rectangula, and Pleuroxus aduncus. Here, we present data on the life table and population dynamics of these three cladoceran species on two types of diets (alga Scenedesmus acutus and detritus). We also analyzed the effect of competition on population growth using Scenedesmus, which proved to be the better diet than detritus. We hypothesize that feces of the larger cladoceran species (S. vetulus) could be a food source for the smaller taxa (A. rectangula and P. aduncus). Experiments were conducted in 100 ml beakers with 50 ml of medium in each at a temperature of 23 ± 1°C. We studied the demography of three test species using two food types with four replicates for each treatment in the life table experiments. Based on the data thus obtained we further studied the competition between the cladocerans on a diet of Scenedesmus. The maximal growth rates obtained for P. aduncus, S. vetulus, and A. rectangula fed Scenedesmus acutus were: 0.1, 0.3, and 0.5 d−1, respectively. Among the test species, S. vetulus had the highest survivorship of 77 days when cultured on detritus and P. aduncus the lowest of 20 days on Scenedesmus. The gross reproductive rate (offspring female−1 lifespan−1) ranged from 6 neonates in Pleuroxus to 160 in Simocephalus per female. From the competition experiments conducted using alga as the diet, we observed that A. rectangula and, especially P. aduncus, had higher growth rates in the presence of S. vetulus than in the controls. This facilitation could be one of the reasons for higher species diversity in the littoral of water bodies.  相似文献   

8.
Takahashi  Haruki 《Mycoscience》1999,40(1):73-80
Two lignicolous species ofMycena (Agaricales, Basidiomycetes) are described and illustrated from eastern, Japan:Mycena auricoma sp. nov., forming ephemeral coprinoid basidiomata and belonging to sectionRadiatae, was found on a dead fallen twig ofQuercus serrata. It appears to close to a Malaysian species,“Trogia” crinipelliformis. Mycena spinosissima in sectionSacchariferae, new to Japan, was collected from dead bark ofAphananthe aspera, a dead fallen inflorescence ofCryptomeria japonica, and a dead fallen twig ofQuercus serrata.  相似文献   

9.
The complete mitochondrial genome (mtDNA) of snow leopard Panthera uncia was obtained by using the polymerase chain reaction (PCR) technique based on the PCR fragments of 30 primers we designed. The entire mtDNA sequence was 16 773 base pairs (bp) in length, and the base composition was: A—5,357 bp (31.9%); C—4,444 bp (26.5%); G—2,428 bp (14.5%); T—4,544 bp (27.1%). The structural characteristics [0] of the P. uncia mitochondrial genome were highly similar to these of Felis catus, Acinonyx jubatus, Neofelis nebulosa and other mammals. However, we found several distinctive features of the mitochondrial genome of Panthera unica. First, the termination codon of COIII was TAA, which differed from those of F. catus, A. jubatus and N. nebulosa. Second, tRNASer (AGY), which lacked the ‘‘DHU’’ arm, could not be folded into the typical cloverleaf-shaped structure. Third, in the control region, a long repetitive sequence in RS-2 (32 bp) region was found with 2 repeats while one short repetitive segment (9 bp) was found with 15 repeats in the RS-3 region. We performed phylogenetic analysis based on a 3 816 bp concatenated sequence of 12S rRNA, 16S rRNA, ND2, ND4, ND5, Cyt b and ATP8 for P. uncia and other related species, the result indicated that P. uncia and P. leo were the sister species, which was different from the previous findings.  相似文献   

10.
A brown blotch bacterium,Pseudomonas tolaasii strain PT814, expresses a high degree of cross-protection against generalized stress imposed by physical/chemical treatment, H2O2, UV, high temperature, ethanol and NaCl during the interaction withPleurotus ostreatus. Stress resistance was also noted in the bacterium in vitro under limited carbon and nitrogen sources. In addition, changes in cell morphology from a “metabolically active” rod to an “energy-saving” spherical shape were detected during starvation and the interaction. All the changes under stress were reversible. A homologue ofrpoS (σ S), a regulator that controls such physiological status during starvation in other bacteria, was identified inP. tolaasii strain PT814. Data suggest that the bacterium is able to withstand a complex stress environment for its survival through changes in its metabolic pattern.  相似文献   

11.
The exopolysaccharide (EPS) is an extracellular molecule that in Bradyrhizobium japonicum affects bacterial efficiency to nodulate soybean. Culture conditions such as N availability, type of C-source, or culture age can modify the amount and composition of EPS. To better understand the relationship among these conditions for EPS production, we analyzed their influence on EPS in B. japonicum USDA 110 and its derived mutant ΔP22. This mutant has a deletion including the 3′ region of exoP, exoT, and the 5′ region of exoB, and produces a shorter EPS devoid of galactose. The studies were carried out in minimal media with the N-source at starving or sufficient levels, and mannitol or malate as the only C-source. Under N-starvation there was a net EPS accumulation, the levels being similar in the wild type and the mutant with malate as the C-source. By contrast, the amount of EPS diminished in N-sufficient conditions, being poyhydroxybutyrate accumulated with culture age. Hexoses composition was the same in both N-situations, either with mannitol or malate as the only C-source, in contrast to previous observations made with different strains. This result suggests that the change in EPS composition in response to the environment is not general in B. japonicum. The wild type EPS composition was 1 glucose:0.5 galactose:0.5 galacturonic acid:0.17 mannose. In ΔP22 the EPS had no galactose but had galacturonic acid, thus indicating that it was not produced from oxidation of UDP-galactose. Infectivity was lower in ΔP22 than in USDA 110. When the mutant infectivity was compared between N-starved or N-sufficient cultures, the N-starved were not less infective, despite the fact that the amounts of altered EPS produced by this mutant under N-starvation were higher than in N-sufficiency. Since this altered EPS does not bind soybean lectin, the interaction of EPS with this protein was not involved in increasing ΔP22 infectivity under N-starvation.  相似文献   

12.
A new species ofFusarium, F. nisikadoi, isolated fromPhyllostachys nigra var.henonis (bamboo) andTriticum aestivum (wheat) in Japan, is described, illustrated and discussed. This species is differentiated from other known species of the genus by the following characteristics: whitish colony color, long zigzag-like chains of 0–3(-5)-septate clavate conidia, intermixed with pyriform conidia, produced mostly from monophialides and rarely from polyphialides in the aerial mycelium, very long and slender sporodochial conidia, and no chlamydospores. The long chains of septate conidia are known only in this species of the genusFusarium. The conidiophores on the aerial mycelium sometimes proliferate sympodially. The species is tentatively placed in the form-sectionLiseola.  相似文献   

13.
A new long-snouted whipray, Himantura lobistoma, is described on the basis of seven specimens collected from the southeastern sector of the South China Sea, off western Borneo. It belongs to a subgroup of Himantura species provisionally defined herein as the “uarnacoides” complex that includes five nominal species: H. chaophraya, H. granulata, H. hortlei, H. pastinacoides, and H. uarnacoides. These whiprays all have a similar lateral disc shape (i.e., pectoral-fin apices broadly rounded rather than narrowly rounded or angular), a plain colouration (i.e., usually uniform light to dark brown dorsally, and pale or whitish ventrally with or without a dark margin), a long and slender whiplike tail, and platelike denticles in a broad dorsal band in adults. Himantura lobistoma can be distinguished from the superficially similar H. hortlei by its highly protrusible mouth and pelvic girdle with prominent lateral prepelvic processes. It differs from other members of the “uarnacoides” complex by a combination of internal and external morphological characteristics (e.g., having an extremely elongate snout and very small eyes). Another long-snouted stingray from the region, Dasyatis microphthalmus Chen, inadequately described and known only from the lost holotype, is considered a nomen dubium. It had been assigned to Himantura based on the absence of an obvious ventral cutaneous tailfold but may be conspecific with D. acutirostra.  相似文献   

14.
A phylogeographic analysis of two bagrid catfishes in Taiwan was conducted using sequence data from a portion of the mitochondrial DNA (mtDNA) control region. For Pseudobagrus brevianalis, which is most probably endemic to Taiwan, a total of eight haplotypes were detected in 189 specimens from nine river systems covering its entire distribution range, from northern to central western areas of the island. Obvious genetic differentiation was observed among its populations (average F ST = 0.753); in particular, the northernmost Tamsui River population was fixed for a single endemic haplotype. Nested clade phylogeographic analysis (NCPA) indicated that the dispersal center of mtDNA was the area around the Touchien River and Holong River, north to the Miaoli Plateau, in northwestern Taiwan, suggesting both northward and southward dispersal in this species. There was no evidence for the validity of P. taiwanensis, the nominal species described from Taiwan, morphologically similar to P. brevianalis. We confirmed that P. adiposalis was distributed discontinuously in three river systems; analysis of 42 specimens from the rivers indicated a total of four haplotypes and population differentiation (average F ST = 0.876). Fixation into a largely differentiated haplotype in the northernmost Tamsui River population was also found in this species, but different processes for this phylogeographic pattern were implied for the two species. Comparison with P. ussuriensis, a widespread continental species morphologically similar to P. adiposalis, suggested the possibility that P. adiposalis is a group of local populations of P. ussuriensis in Taiwan. Two migration routes vs. random fixation scenarios for the population structure of P. adiposalis are discussed with information on other fishes and the geological history of the island.  相似文献   

15.
Miconia howardiana, which is known only from a diverse moist montane forest in the vicinity of Loma Trocha de Pey (or “Monteada Nueva”), the easternmost peak of the Sierra de Baoruco, is described and illustrated. It is compared to phenetically similar (and probably phylogenetically related) species of theMiconia favosa complex, i.e.,M. favosa, M. xenotricha, M. campanensis M. Sintenisii, M. foveolata, andM. pycnoneura. The species of this complex are characterized by bullate leaves with frequently cordate bases and often six secondary veins. Most species also have large berries and flowers, 5-locular ovaries, large inflorescence bracts and bracteoles, and more or less dendritic multicellular hairs.  相似文献   

16.
The Ramapithecinae are an extinct, mainly Miocene group of hominoids, whose relationship to modern taxa is disputed. Some regard them as hominids, while others view them as ancestral toPongo,or even as the group ancestral to both hominids and extant apes. In this paper a systematic revision of Ramapithecinae is undertaken. Sivapithecus sivalensis andRamapithecus punjabicus are considered the same species, with the former name having priority. A new Indian species,Sivapithecus simonsi,is recognized. Ramapithecine anatomy is reviewed and compared with that of gracileAustralopithecus, early and middle MioceneProconsul andDryopithecus, and living pongidsPan, Gorilla, andPongo.Ramapithecines are shown to be much more primitive or “ape-like” than some have argued. Anatomical data are evaluated cladistically with several results. Parallel evolution in the jaws, teeth, and facial structure of hominoids appears to be the rule rather than the exception. Bearing this in mind, nevertheless, from the available evidence of anatomy, ramapithecines are cladistically hominids.  相似文献   

17.
Pictolejeunea reginae, a new species from Venezuela is described and illustrated. It is the type of the new subgenusNeopitolejeunea Ilkiu-Borges, which is characterized by entire underleaves. A key to the two subgenera and four known species ofPictolejeunea is provided.
Ilkiu-Borges, A. L. (Museu Paraense Emílio Goeldi, C. P. 399, Belém, Pará, CEP 66040-170. Brasil: email: ilkiuborges@hotmail.com).Pictolejeunea reginae, a new species of Lejeuneaceae (Hepaticae) from Venezuela. Brittonia 54: 318–321. 2002.—Pictolejeunea reginae, uma nova espécie encontrada na Venezuela, é descrita e ilustrada. A espécie é tratada como tipo do novo subgêneroNeopictolejeunea Ilkiu-Borges, caracterizada pelos anfigastros inteiros. é apresentada uma chave para os dois subgêneros e as quatro espécies dePictolejeunea.
  相似文献   

18.
A new sciaenid,Pennahia ovata, is described from the Bay of Bengal. It differs from its most similar congener,P. anea, in having weakly differentiated teeth on the lower jaw, usually 24–25 dorsal fin soft rays and 18–19 upper+lower gill rakers, a deep body and a long second anal fin spine.  相似文献   

19.
In the course of taxonomic studies on saprobic microfungi from Spain, several slow-growing, dematiaceous hyphomycetes were isolated from soil, submerged plant material and river sediments. Sixteen of these strains were identified as members of the ascomycete order Chaetothyriales on the basis of morphology and DNA sequence analyses of the internal transcribed spacer region and partial large subunit ribosomal RNA gene. These included three novel species (Cladophialophora pseudocarrionii, Cyphellophora chlamydospora, and Rhinocladiella amoena) and five interesting, little-known or clinically-relevant species (Cyphellophora suttonii, Exophiala aquamarina, E. lacus, E. radicis, and Rhinocladiella similis). In addition, Exophiala oligosperma, an emerging opportunistic fungus, was found for the first time in an aquatic freshwater environment (river sediments). Cladophialophora pseudocarrionii resembles C. carrionii in the branching pattern of its conidial chains, but differs from the latter species in its inability to grow at 30 °C. Cyphellophora chlamydospora differs from other species of the genus in the absence of conidiation, producing only chlamydospores in vitro. Rhinocladiella amoena shows branched conidiophores similar to those of R. anceps, R. atrovirens, R. basitona and R. similis, but differs from them in conidial shape and size. The ex-type strain of Phialophora livistonae, included in the phylogenetic study, clustered with high statistical support with members of the genus Cyphellophora and is transferred to this genus.  相似文献   

20.
Phylloicus sp. larvae live on leaf patches in slow flowing waters and build dorso-ventrally flattened cases from leaf pieces. We hypothesized that Phylloicus larvae are selective towards certain leaf species to build a more resistant case. We exposed Phylloicus larvae to equal-area leaf discs of three plant species from the Brazilian Cerrado (Myrcia guyanensis, Miconia chartacea and Protium brasiliense) and one non-native species (Eucalyptus camaldulensis). Phylloicus larvae built cases with discs of all plant species. However, discs of E. camaldulensis and M. guyanensis were used more (36.4% and 35.7%, respectively) than those of P. brasiliense (20.0%). Discs of M. chartacea were used in an intermediate proportion (28.6%). Selection was resource density-dependent, i.e. when P. brasiliense was offered at higher abundance, it was used more frequently by larvae (ANOVA, P < 0.001). Plant species differed in leaf toughness, phenolic concentration and biomass:area ratio (Kruskal–Wallis, P < 0.05). Larvae preferentially used leaves with higher phenolic concentrations (R s = 0.907, P < 0.001) independently of toughness and biomass:area ratio. We suggest that Phylloicus selects for case-building leaves that are chemically protected against microbial degradation and shredder consumption, and this selection depends on leaf abundance. Our results also reinforce the importance of riparian resources and their diversity to the maintenance of aquatic consumers in tropical shaded streams. Handling editor: D. Dudgeon  相似文献   

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