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1.
A phylogenetic analysis is presented, based on 57 morphological, anatomical, chemical and ecological characters, including 19 species from the generaArthonia,ArthotheliumandSyncesia. The aim of the study was to test the monophyly of some of the groups within the genusArthoniasuggested, for example, by Redinger (e.g. species with reddish ascomata, with grey–pruinose ascomata and with brown–black hypothecia). The results strongly support thatArthoniaandArthotheliumare paraphyletic genera. The best-supported node contains allArthoniaspecies together withA. crozalsianade Lesd.,A. ruanaA. Massal. (both hitherto placed inArthothelium) andSyncesia myrticola(Fée) Tehler. A well-supported clade is formed by a group of pioneer species, often non-lichenized or poorly lichenized, including the type species ofArthonia,A. radiata. The species with reddish and/or K+ reddish ascomata form one clade and the species with more or less brownish or blackish hypothecia form another clade withSyncesia myrticola, the sister group to theOpegraphaceaeandRoccellaceae. The results are discussed and compared with Redinger’s grouping. Relationships to other genera within Arthoniaceae are briefly discussed.Arthothelium scandinavicumTh. Fr.,Arthonia dispersa(Schrad.) Nyl.,A. punctiformisAch. andA. mediellaNyl. are lectotypified.  相似文献   

2.
Twenty-one flavonoids were isolated from the leaves of two endemic species ofMyrceugenia on the Juan Fernandez Islands,M. fernandeziana andM. schulzei, from two related species from Brazil,M. campestris andM. rufescens, and from five species from continental Chile,M. colchaguensis, M. exsucca, M. lanceolata, M. pinifolia, andM. rufa. A phenetic analysis was used to evaluate chemical similarities.Myrceugenia campestris andM. rufescens appear most closely related to each other based on flavonoid profiles, and they are also different from the other seven species. The two endemic species in the Juan Fernandez Islands,M. fernandeziana andM. schulzei, group with the continental Chilean species. The former is most closely related toM. lanceolata, and the latter clusters withM. exsucca, although somewhat distantly. The results suggest that the two Juan Fernandez endemics are derived from two introductions from the Chilean continent and not from immigrants from the eastern side of the Andes.  相似文献   

3.
Eleven chromosome counts are reported for Brazilian populations of eight species ofAndropogon. Counts for five of the species are first reports for the species. Four of these species,A. arenarius, A. glaziovii, A. lateralis, andA. lindmanii, are hexaploids (n=30) and belong to a group of about a dozen species informally referred to as theAndropogon lateralis complex. Two other species of this complex,A. bicornis andA. hypogynus, we also found to be hexaploids, in agreement with previous reports. Diploid counts (n=10) forA. macrothrix (a first report) andA. virgatus (the same as two previous reports) support the morphological affinities of these two species to other species complexes withinAndropogon.  相似文献   

4.
5.
A comparison of three heretofore undescribed species with the previously known species inTigridia subgen.Hydrotaenia suggests a realignment of taxa within the various complexes inHydrotaenia. Three species,T. venusta, T. illecebrosa, andT. catarinensis, and two subspecies,T. hallbergii ssp.lloydii andT. ehrenbergii ssp.flaviglandifera, are described.Sessilanthera citrina is described and the new taxonomic combinationS. heliantha (Ravenna) Cruden is proposed.  相似文献   

6.
Habenaria sect.Macroceratitae from Brazil is revised, and seven species are recognized:H. bractescens, H. gourlieana, H. johannensis, H. longicauda, H. macronectar, H. nabucoi, and the newly describedH. paulistana. A main feature of these species is the presence of long, separated, involute stigmatic processes.Habenaria bractescens, H. gourlieana, H. johannensis, andH. macronectar are distributed mainly from central and southeastern Brazil to southern Brazil and southern South America, whereasH. longicauda andH. nabucoi are distributed mainly from west central, southeastern and northeastern Brazil to northern South America.Habenaria paulistana is restricted to the state of São Paulo.Habenaria bradei, H. juergensii, andH. sartoroides are lectotypified, andH. kleyi is neotypified. The identity ofH. fastor is discussed andH. nabucoi is recognized as the valid name for this species. Seven other species previously placed in sect.Macroceratitae are sufficiently distinct and are removed from the section.  相似文献   

7.
Immersaria olivacea, its lichenicolous fungusPolycoccum decolorans, andImmersaria mehadianaare described as new species from Spain and Romania, respectively. A new combination,Immersaria cupreoatrais proposed, and a revised concept of the generaBellemereaandImmersariais supplied.  相似文献   

8.
A comparison of some genera of the Condaminecae (Rubiaceae) with a few taxa of closely related tribes (Rondeletieae, Calycophylleae, and Cinchoneae) revealed that some species ofChimarrhis (Condamineeae s. 1.),Bathysa (Rondeletieae), andCalycophyllum (Calycophylleae) are often misassigned to genera. The taxonomic significance of calycophylls is discussed; the generic boundaries ofChimarrhis, Bathysa, andCalycophyllum are reevaluated; and their similarities and differences are discussed. As a result, a new calycophyllous species ofChimarrhis from the Amazon,C. gentryana, is described, two of its species are transferred toBathysa (B. Bathysoides, B. perijaënsis), and one species ofBathysa (B. difformis) is reduced to synonymy underChimarrhis (C. turbinata).  相似文献   

9.
Psathyrella hypertropicalis, a new species, is described from a high mountain (Cofre de Perote) in the State of Veracruz, Mexico above the subtropical zone. This species is intermediate betweenP. velutina of the temperate regions andP. sepulchralis from the subtropical regions of Mexico. A list of the 26 species ofPsathyrella of Mexico is presented, of which 21 are from the tropics and subtropics, three from the temperate regions (P. velutina, P. spadicea, andP. hypertropicalis), and two with a broad distribution (P. candolleana andP. disseminata). Eleven are only known from Mexico.  相似文献   

10.
A chromosome number ofn=12 is reported for the three monotypic genera of subtribe Castillejinae:Clevelandia beldingii, Gentrya racemosa, andOpicopephalus angustifolius. Chromosome numbers ofOrthocarpus correspond mostly with current infrageneric classification. SubgenusTriphysaria hasn=11.Orthocarpus sectionsCastillejoides andCordylanthoides, which are closely related toCastilleja (x=12) and the three monotypic genera above, haven=12 with aneuploid reductions ton=10 inO. linearilobus andn=11 inO. lacerus (a species also withn=12). Tetraploids are found in two species.O. brevistylus (n=24) andO. hispidus (n=12, 24). The polyploid.O. laciniatus (n=36, 48) of Peru is postulated to be of hybrid origin between a species ofCastilleja andOrthocarpus attenuatus. SubgenusOrthocarpus sectionOrthocarpus, which hasn=14 in all species except.O. bracteosus (n=15), stands apart both morphologically and in chromosome number from the remainder of the genus.  相似文献   

11.
The species ofArthonias. lat. (Arthoniales,Ascomycotina) lichenicolous on species ofPseudocyphellariaand otherLobariaceaeare revised. Thirteen species are accepted, and eight species are described as new (all from the Southern Hemisphere):Arthonia badiaWedin & Hafellner,A. coriifoliaeWedin & Hafellner,A. flavicantisWedin & Hafellner,A. maculiformisWedin & Hafellner,A. minutaWedin & Hafellner,A. santessonianaWedin & Hafellner,‘A.’ semi-immersaWedin & Hafellner, andA. subaggregataWedin & Hafellner. Comparative notes on additional accepted species previously described fromPseudocyphellariaor otherLobariaceae(A. pelvetii,A. plectocarpoides,A. pseudocyphellariae,A. stictaria, andA. subconveniens) are included, and a key to theArthonia(and similar) species growing onLobariaceaeis presented. The coelomycete genusSubhysteropycnisWedin & Hafellner is described for the speciesS. maculiformansWedin & Hafellner, the macroconidal anamorph ofArthonia badia. The lecanoralean genusCorticiruptorWedin & Hafellner is described as new to accommodate the single lichenicolous speciesC. abeloneae(P. M. Jørg.) Wedin & Hafellner comb. nov., and the additional new combinationPlectocarpon linitae(R. Sant.) Wedin & Hafellner is proposed. The namesCelidium pelvetiiHepp,Sticta auratababortivaSchaer. andArthonia stictariaNyl. are lectotypified, and the typifications are discussed.  相似文献   

12.
13.
Arceuthobium pendens, a parasite of the pinyonsPinus discolor andP. cembroides, is described from San Luis Potosí and Veracruz, Mexico. This andA. divaricatum Engelm. are the only dwarf mistletoes known to parasitize pinyons.Arceuthobium pendens is distinct fromA. divaricatum Engelm. in its long, slender, greenish shoots, formation of systemic witches brooms, and frequency on various species of pinyons. With the discovery of this new species, 19 dwarf mistletoes are known from Mexico.  相似文献   

14.
15.
John R. Reeder 《Brittonia》1971,23(2):105-117
Chromosome numbers are reported for 105 collections which represent 59 species belonging to 35 genera. For two of these genera:Blepharoneuron andTriniochloa no documented chromosome counts have been published to date. Records for the following species:Aristida arizonica, A. pansa, A. schiedeana, Blepharoneuron tricholepis, Deschampsia pringlei, Eragrostis palmeri,Leptochloa viscida, Munroa squarrosa, Panicum vaseyanum, Setaria grisebachii, andTriniochloa stipoides are the first for these taxa. Counts of 2n = 28 forAgrostis perennans, 2n = 20 forAegopogon cenchroides, 2n = 20 forBuchloË dactyloides, 2n = 54 forDigitaria filiformis, 2n = 60 and 2n = ca. 74 forEragrostis intermedia, 2n = 32 forErioneuron grandiflorum andE. pilosum, 2n = 44 forHilaria cenchroides, 2n = 38 and 2n = ca. 180 forHilaria mutica, 2n = 40 forPereilema crinitum, 2n = 28 forScleropogon brevifolius, 2n = ca. 108 forSetaria leucopila, and 2n = 36 forOplismenus burmannii are different from any published report for these species. Cytological information on Mexican material of the following ten species:Agrostis perennans, Aristida hamulosa,Bouteloua aristidoides, Eragrostis cilianensis, Sporobolus nealleyi, Tridens muticus,Digitaria filiformis, Hackelochloa granularis, Oplismenus burmannii, andPennisetum ciliare is here presented for the first time.  相似文献   

16.
Lynn G. Clark 《Brittonia》1992,44(4):387-422
The 13 high altitude/latitude, dwarf species ofChusquea in Brazil are described, illustrated, and mapped, and their morphology, habitats, distributions, and taxonomic affinities are discussed. Two keys to species are provided, one based solely on vegetative characters, and the other on vegetative and flowering characters.Chusquea erecta, C. nutans, C. riosaltensis,C. windischii, C. caparaoensis, andC. nudiramea are described as new, andC. microphylla is elevated to specific status. Two subspecies are recognized within the variableC. mimosa: C. mimosa subsp.australis and subsp.mimosa. Seven species are formally classified withinChusquea sect.Swallenochloa; the remaining six species are classified into two informal categories, theNudiramea andHeterophylla groups. A list of all the species currently included withinChusquea sect.Swallenochloa is provided.  相似文献   

17.
《Experimental mycology》1989,13(2):183-195
The fatty acids and sterols of eight Chytridiomycetes and two Hyphochytriomycetes, and fatty acids of the OomycetePythium gracile, were analyzed by gas-liquid chromatography. In addition to the fatty acids anticipated for fungi, the two Hyphochytriomycetes (Hyphochytrium catenoides andRhizidiomyces apophysatus) and four of the Chytridiomycetes (Catenaria anguillulae, Blastocladiella emersonii, Monoblepharella sp., andAllomyces macrogynus) contained arachidonic acid as a major fatty acid of the polar lipid fraction, and this fatty acid was detected as a minor component ofRhizophlyctis rosea andSpizellomyces punctatum. Eicosapentaenoic acid constituted 4.6% of the polar lipid fatty acids inMonoblepharella sp., and trace amounts were detected in several other species. Both the gamma (ω-6) and alpha (ω-3) isomers of linolenic acid were detected in all of the species analyzed. Cholesterol was the predominant (≥73%) sterol ofB. emersonii, R. rosea, A. macrogynus, andChytridium confervae, and a minor (<12%) component ofC. anguillulae, andH. catenoides. The major sterols of the other species included lanosterol (C. anguillulae, 45%), stigmasta-5,22-dien-3β-ol (H. catenoides, 51%), 24-ethyl-cholesterol (S. punctatum, 38%;H. catenoides, 17%;Monoblepharella sp., 70%; andR. apophysatus, 84%), 24-methyl-cholesterol (H. catenoides, 23%;R. apophysatus, 14%;S. punctatum, 53%), and 24-methylene cholesterol (Rhizophydium sphaerotheca, 51%). Neither ergosterol nor fucosterol was detected in any of the species studied.  相似文献   

18.
Ten species ofCarex and one species ofKobresia from Thailand are taxonomically discussed, and some new range extensions into Thailand are noted. Described as new areCarex subinclinata andC. thailandica, both belonging to the sectionIndicae, andC. speciosa ssp.latifolia of the sectionRadicales. Two new combinations proposed areCarex helferi ssp.mapanifolia, andC. speciosa ssp.platyrhina.  相似文献   

19.
20.
长白山云冷杉林幼苗幼树空间分布格局及其更新特征   总被引:5,自引:0,他引:5  
杨华  李艳丽  沈林  亢新刚  岳刚  王妍 《生态学报》2014,34(24):7311-7319
长白山云冷杉针阔混交林是我国东北主要的森林类型之一,其乔木树种幼苗幼树的结构和动态决定着未来林分的结构和生长动态。在长白山地区设置一块具有代表性的云冷杉针阔混交林幼苗幼树更新样地,统计分析幼苗幼树更新特征,绘制地径结构图、树高结构图及其空间分布图。运用点格局分析中的单变量O-ring统计方法,分析更新树种的空间分布格局;用双变量O-ring统计方法,分析更新树种种间的空间关联性。研究结果表明:(1)更新树种组成有冷杉(Abies nephrolepis)、色木槭(Acer mono)、紫椴(Tilia amurensis)、红皮云杉(Picea koraiensis)、红松(Pinus koraiensis)、蒙古栎(Quercus mongolica)、春榆(Ulmus japonica)7种,其中以冷杉、色木槭为主,更新幼苗幼树的地径近似呈倒J型分布,树高结构近似呈双峰分布;(2)所有更新树种、冷杉、色木槭在小尺度1—10 m的范围内呈聚集分布,随着尺度增加,聚集程度减弱,逐渐趋于均匀分布和随机分布,紫椴、云杉和红松在空间所有尺度上以随机分布为主;(3)更新树种之间的空间关联性在小尺度范围上正关联性比较多,较大尺度范围上负关联性比较多,随着尺度增加,空间关联性减弱。  相似文献   

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