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1.
A summary is presented of all Peruvian species of scaly tree ferns (Cyatheaceae). A total of 83 species is native to Peru (Sphaeropteris 1 sp., Alsophila sect. Alsophila 9 spp., Alsophila sect. Gymnosphaera 1 sp., Cyathea 72 spp.), with 13 endemic species in Cyathea and one in Alsophila. The following new species are described and illustrated: Alsophila gastonyi, Cyathea chontilla, C. nephele, C. polliculi, and C. praetermissa. The genera Cnemidaria and Trichipteris are no longer recognized and merged in Cyathea. Necessary combinations are made for Cyathea alatissima, C. nervosa, and C. uleana. Cyathea serpens is presented in detail and its relationship is discussed. An artificial key to the Peruvian species of Cyatheaceae is provided.  相似文献   

2.
Morphological and plastid rbcL and trnG-R sequence data suggest that the fern currently recognized as Megalastrum lasiernos (Dryopteridaceae) is in fact a tree fern (Cyatheaceae) and a member of the Cyathea clade. Accordingly, a new combination is made: Cyathea myriotricha. Based on morphological and ecological similarities, this species appears most closely related to C. aterrima. Both species are described and illustrated herein.  相似文献   

3.
Aaron B. Shiels 《Biotropica》2006,38(3):348-353
Decomposition is a critical process for nutrient release and accumulation of soil organic matter in disturbed soils, such as those found on landslides. I conducted a decomposition experiment on five landslides in the Luquillo Mountains of Puerto Rico as part of an investigation of the successional roles of two of the most common plant colonists to landslides, Cecropia schreberiana Miq. (Cecropiaceae) a pioneer tree species, and Cyathea arborea (L.) Sm. (Cyatheaceae) a pioneer tree fern. I compared leaf litter decomposition over one year and the initial and 1‐yr chemistry for both species. Initial litter chemistry differed between the two species, as Cecropia had slightly higher nitrogen (9.2 mg/g) than Cyathea (8.2 mg/g) and higher lignin (28.6%) than Cyathea (26.0%), but water‐soluble carbon and nonpolar extractable carbon (fats and oils, waxes, chlorophylls) were higher in Cyathea than Cecropia. Total carbon, acid‐soluble carbon, total phosphorus, and pH did not differ significantly between leaf litter species. Across all five landslides, Cyathea (k= 0.93 ± 0.06) leaves decomposed significantly faster than Cecropia (k= 0.68 ± 0.06). The differences in these species leaf litter decomposition rates and chemical composition could potentially influence organic matter dynamics and nutrient cycling rates in these early successional systems.  相似文献   

4.
Spore sculpture and wall structure of eight Cyathea (Cyatheaceae) species from southern South America were studied using light microscopy (LM), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) techniques. Two layers, i.e. an inner and an outer layer, were observed in the perispore. The inner layer has two strata: the inner stratum is attached to the exospore and composed of rodlets tangentially oriented to the spore surface and randomly intermixed; the outer stratum consists of a three-dimensional network of rodlets with either free or fused distal edges forming spinules. The outer layer is thin, darkly contrasted and covers the rodlets. In most cases, the exospore has two layers and a pitted surface. In Cyathea atrovirens, the exospore surface is smooth, while in C. delgadii and C. myriotricha it is verrucate. The homogeneity of perispore features within the genus Cyathea is evident, while exospore features are heterogeneous. The exospore has different kinds of surface-structures that are of potential interest for assessing evolutionary trends within the group.  相似文献   

5.
运用对PCR产物直接测序和克隆后测序的方法测定了蚌壳蕨科1种和桫椤科11种(其中桫椤分别测定19株:小羽桫椤测定2株)植物的叶绿体trnL基因内含子和trnL-trnF基因间隔区序列。12种植物相应的长度介亍l004-l082之间,A T平均含量60.9%,G C平均含量39.1%。计算了不同种间以及种内不同个体间序列的碱基差别(转换值/颠换值)和Kimura遗传距离。序列数据经排列后分别进行最简约法、最大似然法和邻接法分析,结果显示:(1)白桫椤、海南白桫椤和大羽桫椤构成的分支最早和该科内其余植物组成的另一分支分歧,而后者又进一步分为刃个亚分支,分别和桫椤亚属、黑桫椤亚属对应,支持夏群的分类处理:(2)大桫椤~狭羽桫椤~毛轴桫椤~篦齿桫椤、多羽桫椤一白桫椤~海南白桫椤以及小羽桫椤一桫椤各自构成独立、自然的末端分支,再参照分支内植物间的遗传距蔼取值,建议将此3个末端分支依次归并为3种:大桫椤、白桫椤和桫椤;(3)白桫椤属在科内处于基部位置,桫椤属奇桫椤亚属和黑桫椤亚属为衍生分支,赞同Tryon关于桫椤科进化和囊群盖起源的假说。  相似文献   

6.
Marcus Lehnert 《Brittonia》2004,56(3):210-212
A new species of Cyatheaceae is described and illustrated:Cyathea bettinae. It is a small tree fern from the mountain forest of northwestern Bolivia.  相似文献   

7.
8.
Abstract Litterfall is an important cause of damage and mortality to seedlings in many forest ecosystems. This study is the first to investigate the contribution of variable risk of litterfall damage to microsite heterogeneity. Two hundred artificial seedlings were ‘planted’ in the ground at 2‐m intervals along transects in each of two New Zealand forests, and all plant species with foliage directly above each artificial seedling were recorded. Additional artificial seedlings were planted on the ground underneath treeferns and on their trunks (epiphytically). The artificial seedlings were monitored monthly for damage over 2 years. Three overtopping species that cause litterfall damage, along with one species that impedes litterfall, produced different microsites with a hierarchy of litterfall damage risk to seedlings (2–30% per year). This risk differed significantly among microsites (P < 0.0005). Seedlings differ in resilience to litterfall and, therefore, microsites with different litterfall risks provided the potential for regeneration niche differentiation. More seedlings were damaged beneath Cyathea dealbata (Cyatheaceae), which drops whole fronds, than on its trunks. The reverse was found for Dicksonia fibrosa (Dicksoniaceae), which retains dead fronds as a ‘skirt’. We suggest that shedding whole fronds, or producing a skirt of fronds, are alternative ‘strategies’ that can reduce competition from terrestrial and epiphytic seedlings, respectively.  相似文献   

9.
Paracyathocaulis ogurae gen. et comb. nov. andCyathocaulis yezopteroides sp. nov. are Late Cretaceous tree-fern stems with cyatheaceous affinity. They are comparable with the Recent scaly cyatheoids (Cyathea s.l.), as well as with the Cretaceous and Tertiary fossil stems that have similar anatomy. All of these tree ferns, including the Late Jurassic to Early CretaceousOguracaulis Tidwellet al., comprise a well-defined morphological complex within Cyatheaceae, and are considered to be monophyletic. The taxonomy of this complex is analyzed cladistically, and the cladogram is phylogenetically evaluated by reference to the chronological data of fossils.  相似文献   

10.
A synopsis of all Neotropical species of Cyathea with bipinnate fronds is presented. This artificial group includes 27 species with entire or very shallowly lobed pinnules. The provided key includes together, for the first time, species that had been previously treated in three different genera: Sphaeropteris, Trichipteris, and Cyathea. Full synonymy and geographic distribution is provided for each species. A second-step lectotype is designated for Cyathea marginalis.  相似文献   

11.
Palynological assemblages are reported for the first time for the La Irene Formation, southwestern Santa Cruz Province, Argentina. This unit represents the sedimentation during a regressive period from transitional or delta-plain to fluvial environments. Palynological assemblages are scarce and moderately well preserved. They mainly consist of continental elements (wood remains, cuticles, spores and pollen grains) with scarse marine palynomorphs (dinoflagellate cysts). The spore-pollen assemblages are dominated by fern spores, followed by angiosperm and gymnosperm pollen grains. Bryophyte spores and fungal remains are also present. Among ferns, Cyatheaceae and spores of Laevigatosporites, of uncertain affinity, are dominant. Of the angiosperm pollen, those of Chloranthaceae (Clavatipollenites sp.) and Arecaceae (Arecipites spp., Longapertites sp., Spinizonocolpites hialinus Archangelsky and Zamaloa) are the most abundant. Pollen of Liliaceae (Liliacidites spp.), Proteaceae (Proteacidites sp., Peninsulapollis gillii (Cookson) Dettmann and Jarzen, Retidiporites camachoii Archangelsky) and Ericaceae (Ericipites scabratus Harris) are also present. Gymnosperm pollen is represented by Podocarpaceae (Podocarpidites spp.) and Ephedraceae (Equisetosporites sp.). These palynological suites would represent a fern-angiosperm dominated coastal vegetation, developed under warm and at least locally humid climatic conditions. La Irene Formation is considered Maastrichtian in age based on stratigraphic evidence, which is, in turn consistent with the ages suggested by the species ranges and the similarities observed with others previously described assemblages. This is the southernmost record of Spinizonocolpites, similar to the extant mangrove palm Nypa.  相似文献   

12.
To determine the mycorrhizal status of pteridophyte gametophytes in diverse taxa, the mycorrhizal colonization of wild gametophytes was investigated in terrestrial cordate gametophytes of pre-polypod leptosporangiate ferns, i.e., one species of Osmundaceae (Osmunda banksiifolia), two species of Gleicheniaceae (Diplopterygium glaucum, Dicranopteris linearis), and four species of Cyatheales including tree ferns (Plagiogyriaceae: Plagiogyria japonica, Plagiogyria euphlebia; Cyatheaceae: Cyathea podophylla, Cyathea lepifera). Microscopic observations revealed that 58 to 97 % of gametophytes in all species were colonized with arbuscular mycorrhizal (AM) fungi. Fungal colonization was limited to the multilayered midrib (cushion) tissue in all gametophytes examined. Molecular identification using fungal SSU rDNA sequences indicated that the AM fungi in gametophytes primarily belonged to the Glomeraceae, but also included the Claroideoglomeraceae, Gigasporaceae, Acaulosporaceae, and Archaeosporales. This study provides the first evidence for AM fungal colonization of wild gametophytes in the Plagiogyriaceae and Cyatheaceae. Taxonomically divergent photosynthetic gametophytes are similarly colonized by AM fungi, suggesting that mycorrhizal associations with AM fungi could widely occur in terrestrial pteridophyte gametophytes.  相似文献   

13.
《Journal of bryology》2013,35(2):117-120
Abstract

A key to the forty-two species and four varieties of Grimmia Hedw, and to Coscinodon Spreng. (2 spp) and Hydrogrimmia Loeske (1 sp.) in Europe, including a checklist, is presented.  相似文献   

14.
Comparative anatomical studies of the mature stems of two species each of Trichipteris and Cyathea (Cyatheaceae) are described. The outermost boundary of the stem is typically a two-layered hypodermis. Mucilage-sac cells are randomly distributed in all parenchymatous areas of the stem and form articulated laticifer systems. Localized areas of sclerenchyma tissue occur in the cortex of both T. microphylla and C. suprastrigosa. All species studied possess medullary bundles, whereas cortical bundles are found only in T. trichiata. Accessory bundles occasionally are associated with indentations in the internal stelar sheath of T. trichiata. The stelar pattern in each genus is a dictyostele and consists of individual meristeles. Distinctive cubical cells typically occur wherever sclerenchymatous fibers and parenchyma cells abut one another. Tangential cells occur within the primary phloem of each meristele, and occasionally within the larger accessory bundles. The primary xylem of the adventitious roots is typically diarch, although triarch and tetrarch xylem may occur. Leaf traces and petiole strands are similar anatomically to the accessory bundles. Based upon this study Trichipteris and Cyathea show striking anatomical similarities, and appear to be closely-related taxa.  相似文献   

15.
SUMMARY

Five new Arrenurus spp, from Southern Africa are described: A. amoenus sp. nov. from Natal, A. agnewi sp. nov., A. curtipalpus sp. nov., A. pedatus sp. nov. and A. cavatus sp. nov. from Botswana. The species from Natal came from an older collection belonging to the National Institute for Water Research. The species from Botswana were collected recently by Dr J.D. Agnew1

The water mite fauna of South Africa is only partly known. Therefore it is important that collectors should know that alcohol and formalin are not suitable fixatives. Fixing and storing is most successful in the following mixture: 5 parts glycerin, 2 parts glacial acetic acid and 3 parts water.  相似文献   

16.
The literature on cyatheaceous spore morphology relative to the presence of a perine layer is reviewed, and evidence based on a sodium-hydroxide assay is presented indicating that the outer scultpine layer in certain cyatheaceous spores is perine. Perine so defined characterizes Metaxya, paleotropical and certain neotropical species of Sphaeropteris, nearly all species of Alsophila, all species of Nephelea, and certain species of Trichipteris and Cyathea. It is lacking in Lophosoria, many species of Trichipteris and Cyathea, and all species of Cnemidaria. Two major patterns of spore number per sporangium in the family are reported. Lophosoria, Sphaeropteris, Trichipteris, Cyathea, Cnemidaria, and probably Metaxya are characterized by 64-spored sporangia, whereas most species of Alsophila and all species of Nephelea are characterized by 16-spored sporangia. The congruence of this generic distribution of sporangial-capacity types with Tryon's phyletic arrangement of cyatheaceous genera supports the naturalness of his system. The intrasporangial germination of spores retained in dehisced and dispersed sporangia supports the suggestion that decreased spore number per sporangium in Alsophila and Nephelea may relate to the role of the sporangia as dispersal units. The decreased number of spores per sporangium is associated with a trend toward increase in the number of sporangia per sores, with the highest known count approaching 1000 sporangia per sorus. The Alsophila-Nephelea evolutionary line has probably not been ancestral in the phylogeny of the more advanced groups of ferns.  相似文献   

17.
Eight new species of the genus Tricoma are described from the Mediterranean: Tricoma (Tricoma) apophysis sp.n., Tricoma (T.) latispicula sp.n., Tricoma (T.) corsicana sp.n., Tricoma (T.) pygmaea sp.n., Tricoma (T.) vincxae sp.n., Tricoma (T.) duopapillata sp.n., Tricoma (T.) setosa sp.n. and Tricoma (Quadricoma) tripapillata sp.n.. All are noteworthy for being small.  相似文献   

18.
Examination of the gill lamellae of three sheepshead Archosargus probatocephalus (Walbaum) from the Indian River Lagoon in Florida revealed six species of Monogenoidea: Microcotyle archosargi MacCallum, 1913 (Microcotylidae); Neobenedenia sp. (Capsalidae); and four new species of Euryhaliotrema Kritsky & Boeger, 2002 (Dactylogyridae). The prevalence of all helminths was 100%, except for Neobenedenia sp., which was represented by a single immature specimen. The four new species, Euryhaliotrema carbuncularium n. sp., E. dunlapae n. sp., E. amydrum n. sp. and E. spirulum n. sp., are described and with E. carbunculus (Hargis, 1955) Kritsky & Boeger, 2002 apparently constitute a monophyletic clade of Euryhaliotrema spp. that parasitise sparid hosts in the western hemisphere. The Indian River Lagoon in Florida represents a new locality record for M. archosargi, and the sheepshead is apparently a new host record for a member (Neobenedenia sp.) of the Capsalidae.  相似文献   

19.
The new combination Eudimeriolum cyathearum is proposed for Dimeriella cyathearum; the fungus is found on pinnae of Cyathea caudata in the Philippine Islands. Dimeriella polypodii is described from scales on pinnae of Polypodium montigenum and P. madrense in Mexico. Bioscypha cyatheae, on pinnae of Cyathea sp. in Costa Rica, is redescribed. Bioscypha pteridicola is described from pinnae of Cnemidaria uleana var. abitaguensis in Colombia. Crocicreas sessilis is described from pinnae of Cyathea divergens var. tuerckheimii in Mexico.  相似文献   

20.
The sugar and osmophilic fungal composition of soils amended with five organic substrates (newspaper, orange peel, bromegrass leaves, wheat straw and wood sawdust) was estimated after 2, 4, 6, 8 and 10 weeks using the dilution plate method on glucose and 50% sucrose Czapek's agar media. Wheat straw was the best substrate for total counts of both sugar and osmophilic fungi followed by newspaper, bromegrass leaves, wood sawdust and orange peel. Wood sawdust supported the highest average counts of total sugar fungi, Fusarium, Mucor, Scopulariopsis, Trichoderma and Trimmatostroma spp.; Newspaper, of Aspergillus (8 spp.), Penicillium (4 spp.) and Chaetomium sp. bromegrass leaves of Cladosporium sp., Humicola sp. and Sporotrichum sp.; orange peel, ofAlternaria sp., Circinella sp. and Stachybotrys sp.; and wheat straw, of Botryotrichum sp. and Myrothecium sp. Bromegrass leaves and orange peel supported the highest average counts of total osmophilic fungi, Aspergillus (10 spp.), Cladosporium sp. Paecillomyces sp. and Rhizopus sp.; and of Stemphylium sp., Trichoderma sp., Humicola sp. and Circinella sp. respectively; wheat straw, of Epicoccum sp., Scopulariopsis sp. and Trichothecium sp.; newspaper, of Penicillium (4 spp.) and Alternaria sp.; and wood sawdust of Curvularia sp. and Fusarium (3 spp.). The best colonizers throughout the experimental periods were Aspergilus and Penicillium spp.  相似文献   

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