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1.
The catalogue is based on a comprehensive evaluation of 152 published sources. It includes 624 species (with 4 subspecies and 13 varieties) of lichenized and 17 species of lichenicolous Ascomycota, as well as 9 non-lichenized Ascomycota traditionally included in lichenological literature.  相似文献   

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报道了褐鳞叶衣属Fuscopannaria和鳞藓衣属Psoroma的5个中国地衣型真菌新记录种:蓝缘褐鳞叶衣F.coerulescens、裂叶褐鳞叶衣F.dissecta、泰国褐鳞叶衣F.siamensis、雅褐鳞叶衣F.venusta和鳞藓衣P.hyp-norum.此二属的区别在于褐鳞叶衣属地衣体无下皮层,子实层半淀...  相似文献   

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Lichens result from symbioses between a fungus and either a green alga or a cyanobacterium. They are known to exhibit extreme desiccation tolerance. We investigated the mechanism that makes photobionts biologically active under severe desiccation using green algal lichens (chlorolichens), cyanobacterial lichens (cyanolichens), a cephalodia-possessing lichen composed of green algal and cyanobacterial parts within the same thallus, a green algal photobiont, an aerial green alga, and a terrestrial cyanobacterium. The photosynthetic response to dehydration by the cyanolichen was almost the same as that of the terrestrial cyanobacterium but was more sensitive than that of the chlorolichen or the chlorobiont. Different responses to dehydration were closely related to cellular osmolarity; osmolarity was comparable between the cyanolichen and a cyanobacterium as well as between a chlorolichen and a green alga. In the cephalodium-possessing lichen, osmolarity and the effect of dehydration on cephalodia were similar to those exhibited by cyanolichens. The green algal part response was similar to those exhibited by chlorolichens. Through the analysis of cellular osmolarity, it was clearly shown that photobionts retain their original properties as free-living organisms even after lichenization.Lichens are ubiquitously found in all terrestrial environments, including those with extreme climates such as Antarctica and deserts; they are pioneer organisms in primary succession (Longton, 1988; Ahmadjian, 1993). Colonization ability is largely owed to lichens’ extreme tolerance for desiccation (Ahmadjian, 1993). Although lichens harbor photosynthetic green algae or cyanobacteria (blue-green algae) within their thalli, they show metabolic activity even when dried at 20°C and under conditions of 54% relative humidity (Cowan et al., 1979). This desiccation tolerance partially results from drought resistance originally exhibited by the photobiont. It is further strengthened by lichen symbiosis (Kosugi et al., 2009). Cyanolichens (symbiosis between a fungus and a cyanobacterium) are desiccation-tolerant organisms that favor humid and shady environments, whereas chlorolichens (symbiosis between a fungus and a green alga) tolerate dry and high-light environments (James and Henssen, 1976; Lange et al., 1988). Chlorolichens can perform photosynthesis when the surrounding humidity is high, but cyanolichens require some water in a liquid state (Lange et al., 1986, 2001; Nash et al., 1990; Ahmadjian, 1993).Most poikilohydric photosynthetic organisms can tolerate rapid drying. Biological activity during desiccation and recovery following drought are scarcely affected by protein synthesis inhibitors (Proctor and Smirnoff, 2000). Moderate drought tolerance is attained by increasing compatible solutes (amino acids, sugars, and sugar alcohols) as protective agents during drought stress (Mazur, 1968; Parker, 1968; Hoekstra et al., 2001). An increase in compatible solutes prevents water loss or increases water uptake from the air when humidity is high (Lange et al., 1988). It has been observed, however, that the intracellular solute concentration is low (corresponding to a sorbitol concentration of approximately 0.22 m) in the desiccation-tolerant terrestrial cyanobacterium Nostoc commune (Satoh et al., 2002; Hirai et al., 2004). N. commune photosynthetic activity is lost when incubated in low sorbitol concentrations (Hirai et al., 2004), whereas a Trebouxia spp. chlorobiont freshly isolated from the desiccation-tolerant chlorolichen Ramalina yasudae remains active under the same conditions (Kosugi et al., 2009).Different solute concentrations in photobionts may dictate habitat preferences for chlorolichens and cyanolichens (James and Henssen, 1976; Lange et al., 1988). One might expect that the ideal cellular osmotic pressure (or cellular solute concentration) of a lichenized fungus is problematic, as both the fungus and the photobiont are closely associated in the thallus (Kranner et al., 2005). Thus, we may be able to further hypothesize that the solute concentration itself in original photobionts determines the nature of desiccation tolerance in chlorolichens and cyanolichens.To better understand symbiosis in lichens, it is important to examine how the cellular osmotic pressures of both symbionts contribute to lichen photosynthesis. In this study, cellular osmotic pressures of lichens and photobionts were determined by assessing water potential. The cephalodia-possessing lichen Stereocaulon sorediiferum was chosen as a desiccation-tolerant model organism because it separately harbors a green alga and a cyanobacterium in different compartments of the lichen body. The green algal photobiont is contained in the stem- and branch-like structures, whereas the cyanobacterial photobiont (cyanobiont) is contained in the organism’s cephalodia. For comparison, several chlorolichens (R. yasudae, Parmotrema tinctorum, and Graphis spp.), cyanolichens (Collema subflaccidum and Peltigera degenii), green algae (Prasiola crispa, Trebouxia spp., and Trentepohlia aurea), and cyanobacteria (N. commune, Scytonema spp., and Stigonema spp.) were also analyzed (Fig. 1). The cyanobiont of C. subflaccidum is closely related to N. commune (Ahmadjian, 1993), and the cyanobiont of S. sorediiferum belongs to the genus Stigonema (Kurina and Vitousek, 1999). Green algal photobionts of R. yasudae and S. sorediiferum are Trebouxia spp. (Bergman and Huss-Danell, 1983). For the measurements of water potential, we had to use specimens larger than 0.1 g dry weight for one measurement. Furthermore, the specimens should cover approximately 70% of the surface area of a sample cup with 4 cm diameter that was equipped in our dewpoint potentiometer. Considering the statistical analyses, we needed large amounts of lichen and algal samples for the measurement of water potential. To conduct this study, we wanted to use free-living green algae and cyanobacteria, not the photobionts isolated from a lichen body. This is because inconsistent results were reported previously for chlorobionts liberated from lichens (Brock, 1975; Lange et al., 1990). Three major photobionts of lichens, Trebouxia, Trentepohlia, and Nostoc spp., were considered for inclusion. Until now, free-living Trebouxia spp. were not observed convincingly in nature. Therefore, cultivated Trebouxia spp. were used. Other green algae and cyanobacteria were chosen from among free-living species that (1) are closely related to some photobionts, (2) form large communities sufficient to cover the required quantity that will not destroy the local ecosystem by our sampling, (3) are easy to remove from other attached algae/microorganisms, and (4) are tolerant to desiccation. P. crispa forms large communities in nature, and the closely related species Prasiola borealis is known to be a photobiont of Mastodia tessellata. Only two freshwater species of genus Prasiola are found in Japan; P. crispa inhabits a limited area of Hokkaido Island, and Prasiola japonica is a rare species. P. crispa harvested in Antarctica and shown to be desiccation tolerant in our previous work (Kosugi et al., 2010b) was used in this study.Open in a separate windowFigure 1.Lichens analyzed in this study. A, Cyanolichen C. subflaccidum on a rock. B, Wet (left) and dry (right) thalli of cyanolichen Peltigera degenii with green moss. C, Chlorolichen R. yasudae on a rock. D, Chlorolichen Graphis spp. on a Zelkova serrata tree trunk. The grayish basal part of Graphis spp. is the site where the photobiont resides, and the dark-colored streaks are the apothecia. E, Chlorolichen Parmotrema tinctorum on a Z. serrata tree trunk. F, Cephalodia-possessing lichen S. sorediiferum. Some cephalodia are indicated by arrows. The stem- and branch-like structures are the green algae-containing compartments.  相似文献   

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Parmelioid lichens form a species-rich group of predominantly foliose and fruticose lichenized fungi encompassing a broad range of morphological and chemical diversity. Using a multilocus approach, we reconstructed a phylogeny including 323 OTUs of parmelioid lichens and employed ancestral character reconstruction methods to understand the phenotypical evolution within this speciose group of lichen-forming fungi. Specifically, we were interested in the evolution of growth form, epicortex structure, and cortical chemistry. Since previous studies have shown that results may differ depending on the reconstruction method used, here we employed both maximum-parsimony and maximum-likelihood approaches to reconstruct ancestral character states. We have also implemented binary and multistate coding of characters and performed parallel analyses with both coding types to assess for potential coding-based biases. We reconstructed the ancestral states for nine well-supported major clades in the parmelioid group, two higher-level sister groups and the ancestral character state for all parmelioid lichens. We found that different methods for coding phenotypical characters and different ancestral character state reconstruction methods mostly resulted in identical reconstructions but yield conflicting inferences of ancestral states, in some cases. However, we found support for the ancestor of parmelioid lichens having been a foliose lichen with a non-pored epicortex and pseudocyphellae. Our data suggest that some traits exhibit patterns of evolution consistent with adaptive radiation.  相似文献   

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In the last decades, natural products from lichens have gained more interest for pharmaceutical application due to the broad range of their biological activity. However, isolation of the compounds of interest directly from the lichen is neither feasible nor sustainable due to slow growth of many lichens. In order to develop a pipeline for heterologous expression of lichen biosynthesis gene clusters and thus the sustainable production of their bioactive compounds we have identified and characterized the phosphopantheteinyl transferase (PPTase) EppA from the lichen Evernia prunastri. The Sfp-type PPTase EppA was functionally characterized through heterologous expression in E. coli using the production of the blue pigment indigoidine as readout and by complementation of a lys5 deletion in S. cerevisiae.  相似文献   

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Abstract:A taxonomic revision of the lichenized species of the genus Omphalina in the Iberian Peninsula is presented, based upon fungal and lichen herbarium material, as well as on fresh collections. Relevant morphological and ecological features are discussed and a diagnostic key is provided. Four lichenized species, O. ericetorum, O. hudsoniana, O. meridionalis and O. velutina, are recognized. A squamulose vegetative thallus (Coriscium -type) is present only in O. hudsoniana, while the other three species form a thallus of hyphal globules (Botrydina -type). Anatomical features of the vegetative thallus cannot be used to distinguish between these last three species. Whilst O. hudsoniana is known only from the montane belt of the Eurosiberian Region and O. meridionalis seems to be restricted to the Mediterranean Region, living in more or less humid sites of the Supramediterranean belt, the other two species, O. ericetorum and O. velutina, are widespread.  相似文献   

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The Silurian System by R. I. Murchison
Ellis L. Yochelson. Department of Paleobiology  相似文献   

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The bryophyte Red List of Serbia and Montenegro comprises 254 species (212 mosses and 42 liverworts). Serbia and Montenegro have 39.50% of threatened bryoflora. One moss species is considered as extinct (Encalypta serbica Katic). In the threatened categories there are 20 critically endangered (CR), 35 endangered (EN) and 100 vulnerable (VU) bryophyte species. Seventy-two species are considered to be of low risk, and 36 are too data deficient to place them in any category, but potentially with further investigation will enter one of the threat categories in the Red List.  相似文献   

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This study tries to establish correlations between the types of handedness and several morphophysiological characteristics, controlled by one or a small number of genes with alternative dominant recessive manifestation. The population-genetic homozygosity degree study includes the analysis of the presence, distribution and individual traits combination in left-handed and right-handed persons. It was conducted at three localities in two states, Serbia (SRB) and Montenegro (MNE). Our hypothesis is that a possible genetic load due to increased recessive homozygosity, being a potential population-genetic parameter of left-handedness manifestation, may cause some change in other morpho-physiological characters. The average proportion of 23 studied homozygously-recessive characters (HRC’s) was similar among observed left-handed individuals in the studied localities. It varied from 10.5 ± 0.4 in Serbia to 10.7 ± 0.3 in MNE. The differences were somewhat bigger among right-handed persons, varying from 8.7 ± 0.3 in MNE to 9.1 ± 0.3 HRC’s in Serbia. However, in all localities the average homozygosity was significantly higher among left-handed school children. The number of HRC’s among 400 individuals varied from 2 to 16 among right-handed and from 4 to 19 among left-handed persons. There were no differences in scholar scores between left-handed and right-handed children, although small differences were found between two state samples.  相似文献   

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Biology Bulletin - As part of comprehensive study of lichen diversity of northern areas of Pakistan using molecular and morphological approaches, we found four species of the family Graphidaceae....  相似文献   

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The first record of Pseudorasbora parva in the Balkan region was in 1977 in Sasko Lake, Montenegro and in 1978 it was found in Serbia. Since then, this species has spread to almost all lowland rivers and has become a permanent member of the ichthyofauna in Serbia and Montenegro.  相似文献   

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Examination of the aerial parts of Achillea clavennae afforded eight guaianolides (1-8), three bisabolenes (9-11), four flavonols (12-15), sesamin (lignan) and isofraxidin (coumarin). The structures of the new compounds (2, 4, 5, 7 and 10) were determined by spectroscopic methods. The antiproliferative action of 2, 8, 9 and 12 were tested to HeLa, K562 and Fem-X human cancer cell lines. Guaianolides 2 (9alpha-acetoxyartecanin) and 8 (apressin) showed significant cytotoxic effects to all tested lines and inducumenone (9) exhibited a moderate activity. The most active was flavonol centaureidin (12), already known as cytotoxic compound.  相似文献   

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基于标本馆馆藏标本的信息,研究了中国石蕊属Cladonia地衣及其18个种的垂直分布规律,并确认了本属倾向于分布在高海拔地区的特点。物种随海拔梯度的变化在统计学上呈正态分布或偏正态分布是非常普遍的现象,但是它们的分布规律与其所处的海拔位置相关:物种分布范围随着海拔的增加而缩小。因此,全球变暖会对高海拔地区的物种构成更直接的威胁。粉杆石蕊C.bacillaris和瘦柄红石蕊C.macilenta具有相同的海拔分布规律和分布范围,从生态学的角度支持了它们为同种的观点。  相似文献   

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Serbia and Montenegro together form the Federal Republic of Yugoslavia. As well as the Serb majority this includes the mixed province of Vojvodina, the mainly Albanian population in Kosovo, and the large Muslim minority in Sandzak. Since the start of war in 1991 the attention and sympathies of the world have focused on Bosnia and Croatia. The United Nations imposed economic sanctions on the federal republic in 1992, although in theory medical supplies and aid are exempt. The economy has now collapsed under the triple burden of war, loss of trade between the republics, and UN sanctions. A major public health catastrophe is unfolding in the federal republic.  相似文献   

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Three seaweeds (Halimeda tuna, Codium bursa and Cystoseira barbata) and one seagrass (Cymodocea nodosa) were collected from the Coast of Montenegro, Gulf of Boka Kotorska and their chemical analysis was performed. In seagrass C. nodosa, three phenolic compounds were identified (diosmetin 7‐sulfate, caftaric and coutaric acid). The content of β‐glucan, fatty acids, sterols and micro‐ and macro‐elements were investigated among all samples. The highest content of β‐glucan was detected in C. nodosa seagrass (13.04±0.42 g/100 g). The highest polyunsaturated fatty acids (PUFAs) level was reported in C. barbata, the brown alga (7.157 mg/g), which also had the significant sterol content (fucosterol, 21.76±0.1 μg/g). Green algae, C. bursa and H. tuna, showed the highest level of sterols (β‐sitosterol, 95.21±0.16 μg/g and 73.90±0.08 μg/g, respectively). H. tuna had the highest content of calcium (Ca) in amount of 55125 μg/g. In C. bursa, C. barbata and C. nodosa, the Na/K ratio was low (0.43, 0.46 and 0.69, respectively).  相似文献   

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《Ibis》1878,20(3):209-250
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