桫椤科植物

… A few years ago I began a systematic study of the American Cyatheaceae and this paper is the first report of the work. I recognize eight genera in the family, one of them new and the …

… the taxonomic revision of the species of Cyathea, clade Hymenophyllopsis (Cyatheaceae). … Two indices are presented at the end of the taxonomic treatment: one of accepted names and …

The delimitation of genera and families has been a persistent problem in fern taxonomy, and the Cyatheaceae sensu stricto is no exception. Christensen (190506) adopted clearly artificial genera (Cyathea, Hemitelia, and Alsophila) based on complete (totally surrounding the sorus), partial, and absent indusia. He included Lophosoria and Metaxya in Alsophila. The latter two satellite genera are only distantly related to the major genera of the family, and nowadays are often placed in one or two families of their own. Holttum (1963) proposed a single genus Cyathea for the Flora Malesiana region with two very distinct subgenera, Sphaeropteris and Cyathea. Holttum has maintained (1981, p. 466) that the "only subdivision of the genus clearly definable is that between subgenus Sphaeropteris and the rest." This indicates that Alsophila and Cnemidaria are less distinct from Cyathea than all three are from Sphaeropteris, which is confirmed by the lack of hybrids with Sphaeropteris. In studying the species of the Flora Malesiana region, Holttum came to the fundamental conclusion, among many, that indusium type is not an important generic character, for within a few species it varies widely. Tryon (1970) divided the Cyatheaceae sensu stricto on the basis of scale characters, indusium presence or absence, and venation. He adopted the genera Sphaeropteris (scales conform), Alsophila and Nephelea (scales non-conform and setate), Trichopteris (scales non-conform and non-setate, laminae free-veined, and sori exindusiate), Cyathea (scales non-conform and non-setate, laminae freeveined, and sori indusiate), and Cnemidaria (scales non-conform and non-setate and laminae net-veined. According to Holttum and Edwards (1983, p. 179), this classification has assorted closely related species into Cyathea, Sphaeropteris, and Trichopteris. It is apparent that genera based on these characters are not natural. Working from Tryon's (1970) generic concepts, I have found it possible to define readily recognizable and coherent genera in the Cyatheaceae sensu stricto by including in Cyathea the genus Trichopteris and the New World species considered to be Sphaeropteris, except for the S. horrida group. I accept the genera Sphaeropteris, Alsophila (including Nephelea), Cyathea (including Trichopteris), and Cnemidaria. Occasional hybrids occur within Alsophila and Cyathea and between Cnemidaria and Gyathea. This is evidence of a greater degree of relationship than with Sphaeropteris, but in my opinion should not alone be the basis for adopting an inclusive Cyathea (either excluding or even including Sphaeropteris), for the characteristics of Alsophila and Cnemidaria are sufficiently different from those of Cyathea to distinguish the genera readily, and intergeneric hybrids in ferns

… Informal groupings recognized in previous phylogenetic studies (Conant et al., 1996; Conant and Stein, 2001) appear to be supported in this study as well, although limited taxonomic …

… These scales proved to be much more important for the taxonomy of the family than the indusia on which former subdivisions were based. This was first elaborated by Holttum and Sen (…

Five lectotypes are chosen for basionyms relevant to New Zealand representatives of the fern families Cyatheaceae and Loxsomataceae: Alsophila colensoi Hook.f., Cyathea …

Cyathea pungens, a widespread Neotropical scaly tree fern, is reassessed taxonomically. Based on extensive field observations in South America and the Caribbean, and comparative studies of herbarium specimens and online resources, we define C. pungens as a mainly Amazonian species that extends into the Caribbean but neither beyond west of the Andes nor into the Brazilian Mata Atlantica. Records from west of the Colombian Cordillera Oriental belong to other species, which differ slightly but consistently in the laminar indument (i.e., abundance and color of bullate squamules, and presence of hairs variable vs constant) and prevailing pinnule shape (with only obtuse tips vs acute and obtuse tips). The weak differences in the specimens are generally corroborated by different appearances in the field (i.e., shape of the blades, and number of pinnae) and preferred elevational ranges. The distributions of C. pungens and C. oblonga overlap in the area of the Guyana shield, but C. oblonga is also found along the Caribbean coast and northern lowlands of Colombia and Venezuela. Both species are rarely found above 1000 m and are largely replaced in the mountains by C. klotzschiana (Colombian Cordillera Oriental, Sierra Nevada de Santa Marta and Venezuelan coastal ranges) and C. pastazensis (Colombian Cordillera Central and Occidental as well as eastern Andean slopes of Ecuador). To this group further belongs C. dombeyi from the Andes of Peru and Bolivia, and the reinstated C. pycnocarpa and C. floribunda from Peru and Bolivia. Several additional species are tentatively placed in this group: the northern Andean C. squamata, the Guayanan C. neblinae, Brazilian C. praecincta and Andean C. werffii.

A synopsis of all scaly tree fern species (Cyatheaceae) occurring in Brazil is presented. We recognize 51 species in three genera [Sphaeropteris one species, Alsophila four species (one subspecies, two varieties), and Cyathea 45 species (one variety) ] with 17 taxa being endemic to Brazil. One hybrid endemic to Brazil is recognized. Further included are five species that have not yet been recorded in Brazil, but are expected here because they are found in adjacent countries and occur literally on the border with Brazil. We present the first key covering the family for the whole territory of Brazil.

… The taxonomy of Cyatheales is characterized by instability at the generic and species levels… The worldwide overrepresentation of Cyatheaceae is evident in the flora of tropical America, …

… Spore sculpture and wall structure of eight Cyathea (Cyatheaceae) species from southern South America were studied using light microscopy (LM), scanning electron microscopy (SEM) …

A proposal is made to recognize the following species within Cyathea corcovadensis as currently circumscribed: Cyathea corcovadensis sensu stricto, C. feeana and C. miersii. A common characteristic of the three species is a weak leaf dimorphism, which is most evident in C. miersii where it leads to a high variability of the dissection of the lamina. Cyathea corcovadensis and C. feeana are distinct from C. miersii and other Brazilian tree ferns in having entire pinnules and abruptly reduced, pinnule-like apices on the pinnae. Both species differ from each other in relative and absolute measures of pinnule size and the position of the sori. Cyathea miersii includes all material with pinnatifid pinnules and either abruptly or gradually reduced pinnae. The possibility that it may represent a hybrid complex of C. corcovadensis and/or C. feeana with the common C. atrovirens is discussed.

… of information for studies of the Ameri can Cyatheaceae now in progress. Several of the new … Some of the endemism in the Cyatheaceae in Guayana is reflected in the four new species …

Scaly tree ferns, Cyatheaceae, are a well‐supported group of mostly tree‐forming ferns found throughout the tropics, the subtropics and the south‐temperate zone. Fossil evidence shows that the lineage originated in the Late Jurassic period. We reconstructed large‐scale historical biogeographical patterns of Cyatheaceae and tested the hypothesis that some of the observed distribution patterns are in fact compatible, in time and space, with a vicariance scenario related to the break‐up of Gondwana.

Abstract Background and Aims The tremendously unbalanced distribution of species richness across clades in the tree of life is often interpreted as the result of variation in the rates of diversification, which may themselves respond to trait evolution. Even though this is likely a widespread pattern, not all diverse groups of organisms exhibit heterogeneity in their dynamics of diversification. Testing and characterizing the processes driving the evolution of clades with steady rates of diversification over long periods of time are of importance in order to have a full understanding of the build-up of biodiversity through time. Methods We studied the macroevolutionary history of the species-rich tree fern family Cyatheaceae and inferred a time-calibrated phylogeny of the family including extinct and extant species using the recently developed fossilized birth–death method. We tested whether the high diversity of Cyatheaceae is the result of episodes of rapid diversification associated with phenotypic and ecological differentiation or driven by stable but low rates of diversification. We compared the rates of diversification across clades, modelled the evolution of body size and climatic preferences and tested for trait-dependent diversification. Key Results This ancient group diversified at a low and constant rate during its long evolutionary history. Morphological and climatic niche evolution were found to be overall highly conserved, although we detected several shifts in the rates of evolution of climatic preferences, linked to changes in elevation. The diversification of the family occurred gradually, within limited phenotypic and ecological boundaries, and yet resulted in a remarkable species richness. Conclusions Our study indicates that Cyatheaceae is a diverse clade which slowly accumulated morphological, ecological and taxonomic diversity over a long evolutionary period and provides a compelling example of the tropics as a museum of biodiversity.

… have a unique spore morphology which reinforces the taxonomic distinctness of these genera as … These and the palynological data are discussed in a taxonomic framework. The spore …

… In this article, we reconstruct a climatic niche of scaly tree ferns (Cyatheaceae) using a rigorous analytical procedure which combines climatic niche modelling with reconstruction of …

… Sometimes these groups supported previously suggested taxonomic groupings, but at other times they did not. The New Zealand Asplenium species form four intergrading groups, …

Abstract The simple sequence repeats (SSRs) of plant chloroplasts show considerable genetic variation and have been widely used in species identification and phylogenetic relationship determination. Whether chloroplast genome SSRs can be used to classify Cyatheaceae species has not yet been studied. Therefore, the chloroplast genomes of eight Cyatheaceae species were sequenced, and their SSR characteristics were compared and statistically analyzed. The results showed that the chloroplast genome structure was highly conserved (genome size: 154,046–166,151 bp), and the gene content (117 genes) and gene order were highly consistent. The distribution characteristics of SSRs (number, relative abundance, relative density, GC content) showed taxon specificity. The primary results were the total numbers of SSRs and mononucleotides: Gymnosphaera (61–67 and 40–47, respectively), Alsophila (121–122 and 95–96), and Sphaeropteris (102–103 and 77–80). Statistical and clustering analyses of SSR characteristics showed that their distribution was consistent with the recent classification of Cyatheaceae, which divided the eight Cyatheaceae species into three genera. This study indicates that the distribution characteristics of Cyatheaceae chloroplast SSRs can provide useful phylogenic information at the genus level.

… Evolutionary relationships of 23 species of Cyatheaceae were assessed by comparative … Phylogenetic analyses of restriction site mutations were carried out using both Wagner and …

Sphaeropteris lepifera is a tree fern in the Cyatheaceae, a family that has played an important role in the evolution of plant systems. This study aimed to analyze the complete chloroplast genome of S. lepifera and compared it with previously published chloroplast genomes Cyatheaceae family. The chloroplast genome of S. lepifera comprised 162,114 bp, consisting of a large single copy (LSC) region of 86,327 bp, a small single copy (SSC) region of 27,731 bp and a pair of inverted repeats (IRa and IRb) of 24,028 bp each. The chloroplast genome encoded 129 genes, comprising 32 transfer RNAs, 8 ribosomal RNAs, and 89 protein-coding genes. Comparison of the genomes of 7 Cyatheaceae plants showed that the chloroplast genome of S. lepifera was missing the gene trnV -UAC. Expansion of the SSC region led to the difference in the chloroplast genome size of S. lepifera . Eight genes, atpI , ccsA , petA , psaB , rpl16 , rpoA , rpoC1 , and ycf2 have high nucleic acid diversity and can be regarded as potential molecular markers. The genes trnG-trnR and atpB were suitable for DNA barcodes between different communities of S. lepifera . The S. lepifera groups in Zhejiang Province probably diffused from Pingtan and Ningde, Fujian. The results will provide a basis for species identification, biological studies, and endangerment mechanism of S. lepifera .

The scaly tree ferns, Cyatheaceae, form a large natural group of ca. 640 species. They comprise an ideal model for studying the biogeography of plants due to their broad distribution across the tropical to south-temperate areas of the world. However, tracing the biogeographic history of this highly diversified group has been hampered by unresolved evolutionary relationships among the major clades. Here, we generated transcriptome sequences of five species in three genera of Cyatheaceae (Alsophila, Gymnosphaera, and Sphaeropteris) and used them to search for single-copy nuclear loci for phylogenetic reconstruction. We identified a total of 818 candidate single-copy loci across multiple Cyatheaceae species. To test their phylogenetic utility, we further obtained sequence data of 12 of these loci for 76 samples representing all 13 known species of scaly tree ferns in China and Vietnam. Phylogenetic analyses based on multispecies coalescent and, alternatively, concatenation models yielded congruent results with high resolution. Additionally, we used the 12 loci to identify genetic signals of hybridization. Overall, our results demonstrated that multiple, single-copy loci are informative and efficient tools for phylogenetic or evolutionary studies of scaly tree ferns.

. — Phylogenetic hypotheses about the Cyatheaceae have been based largely on either New World or Old World species. In this study we examine molecular data for species from both hemispheres. Chloroplast DNA restriction site variation has been compared among 23 species of Cyatheaceae from Papuasia and the Pacific and 61 species from the New World. Parsimony analysis of the variation documented supports the existence of three major clades, and reveals a correlation between phylogenetic relationship and biogeography. Species from the Neotropics appear derived with respect to those from the Paleotropics in the Alsophila clade; in this clade species from Papua New Guinea and Lord Howe Island are basal to those from the American tropics. A similar relationship is tentatively suggested for the Cyatheo clade, where the sole Old World representative, (C. howeana] from Lord Howe Island, is basal to the remainder of the clade. This finding extends the worldwide distribution of the Cyathea clade across the Pacific. No clear correlation between phylogeny and biogeography of the Sphaeropteris clade was observed based on current data. These results suggest that additional sampling from other regions in the Old World tropics may further elucidate the evolutionary history of this group of plants.

… Results of this analysis resolve Cyatheaceae SS as monophyletic with the remaining … This apical segment of the tree represents the monophyletic Cyatheaceae SS in our results (…

Abstract DNA barcoding is an effective identification tool for tree ferns with heteromorphic generations with morphologically simple gametophytic phase. A complete reference dataset which includes coverage of the target local flora is necessary for accurate identification. Three different Cyathea sp.pl. were investigated to test the utility of plastid DNA barcode regions rbcL with the intention of developing an identification system for native pteridophytes. In addition, the inter-specific and inter-generic variations among the Cyathea sp.pl. were also focused. BLAST analysis revealed the similar rbcL sequences related to C. nilgirensis Holttum, C. gigantea (Wallich ex Hook. f.) Holttum and C. crinita (Hook.) Copel and a sum of 143 sequences viz., Cyathea sp.pl. (121), Gymnosphaera sp.pl.(4), Sphaeropteris sp.pl. (1) and Alsophila sp.pl. (17). The sequences of 143 plants were retrieved from GenBank in FASTA format. The sequences were aligned using multiple sequence alignment tool MUSCLE. The inter-specific and inter-generic distance percentage were calculated using Maximum Likelihood, Minimum Evolution, UPGMA (Unweighted Pair Group Method with Arithmetic Mean) and Neighbor-Joining method. The analyses were constructed using MEGA X software. The rbcL gene provided sequence variation with its strong resolving power. This study demonstrates the overall effectiveness of DNA barcodes for species identification of tree fern genus Cyathea in the pteridophyte flora of Southern Western Ghats.

… the giant scaly tree ferns (Cyatheaceae), the low, erect plants (… In this study, we investigate phylogenetic relationships within … Our results show that Dicksoniaceae and Cyatheaceae, as …

Present-day geographic and phylogenetic patterns often reflect the geological and climatic history of the planet. Neontological distribution data is often sufficient to unravel a lineage's biogeographic history, yet ancestral range inferences can be at odds with fossil evidence. Here, I use the Fossilized Birth Death process and the Dispersal Extinction Cladogenesis model to jointly infer the dated phylogeny and range evolution of the tree fern order Cyatheales. I use data for 101 fossil and 442 extant tree ferns to reconstruct the biogeographic history of the group over the last 220 million years. Fossil-aware reconstructions evince a prolonged occupancy of Laurasia over the Triassic-Cretaceous by Cyathealean tree ferns, which is evident in the fossil record but hidden from analyses relying on neontological data alone. Nonetheless, fossil-aware reconstructions are affected by uncertainty in fossils' phylogenetic placement, taphonomic biases, and specimen sampling, and are sensitive to interpretation of palaeodistributions and how these are scored. The present results highlight the need and challenges of incorporating fossils into joint inferences of phylogeny and biogeography to improve the reliability of ancestral geographic range estimation.

Present-day geographic and phylogentic patterns often reflect the Gondwana–Laurasia separation and subsequent history of continental drift. However, some lineages show non-overlapping fossil distributions relative to extant species and in some cases extant ‘Gondwanan’ lineages have ‘Laurasian’ extinct relatives. Here, I combined distribution data for 101 fossils and 442 extant species of tree ferns (Cyatheales) to reconstruct their biogeographic history over the last 220 million years. The time calibrated tree showed most tree ferns families originating during the Jurassic and the onset of crown group diversification beginning during the Cretaceous; a major shift in diversification rates occurred in the largest tree fern family (Cyatheaceae) that comprises ~90% of extant diversity in the group. Biogeographical reconstructions based on extant distributions alone supported a Gondwanan origin for the group; the most probable ancestral range encompassed Australasia and South America. Alternatively, incorporating fossil distribution data into reconstructions showed a Laurasian origin and a most probable ancestral range in Eurasia. These results evince the Laurasian legacies of the Cyatheales spanning the Triassic–Cretaceous, which otherwise remain hidden from biogeographic inferences. These results show that extant-only biogeographic analyses are limited when fossils distribution are more wide spread than in the present-day, highlighting the need to directly incorporate fossils into biogeographical analyses and improve the reliability of ancestral geographic range estimation.

Background Cloud forests, characterized by a persistent, frequent or seasonal low-level cloud cover and fragmented distribution, are one of the most threatened habitats, especially in the Neotropics. Tree ferns are among the most conspicuous elements in these forests, and ferns are restricted to regions in which minimum temperatures rarely drop below freezing and rainfall is high and evenly distributed around the year. Current phylogeographic data suggest that some of the cloud forest-adapted species remained in situ or expanded to the lowlands during glacial cycles and contracted allopatrically during the interglacials. Although the observed genetic signals of population size changes of cloud forest-adapted species including tree ferns correspond to predicted changes by Pleistocene climate change dynamics, the observed patterns of intraspecific lineage divergence showed temporal incongruence. Methods Here we combined phylogenetic analyses, ancestral area reconstruction, and divergence time estimates with climatic and altitudinal data (environmental space) for phenotypic traits of tree fern species to make inferences about evolutionary processes in deep time. We used phylogenetic Bayesian inference and geographic and altitudinal distribution of tree ferns to investigate ancestral area and elevation and environmental preferences of Mesoamerican tree ferns. The phylogeny was then used to estimate divergence times and ask whether the ancestral area and elevation and environmental shifts were linked to climatic events and historical climatic preferences. Results Bayesian trees retrieved Cyathea, Alsophyla, Gymnosphaera and Sphaeropteris in monophyletic clades. Splits for species in these genera found in Mesoamerican cloud forests are recent, from the Neogene to the Quaternary, Australia was identified as the ancestral area for the clades of these genera, except for Gymnosphaera that was Mesoamerica. Climate tolerance was not divergent from hypothesized ancestors for the most significant variables or elevation. For elevational shifts, we found repeated change from low to high elevations. Conclusions Our data suggest that representatives of Cyatheaceae main lineages migrated from Australia to Mesoamerican cloud forests in different times and have persisted in these environmentally unstable areas but extant species diverged recentrly from their ancestors.

Knowing how species and communities respond to environmental change is fundamental in the context of climate change. The search for patterns of abundance and phenotypic variation along altitudinal gradients can provide evidence on adaptive limits. We evaluated the species abundance and the variation in morphometric and stomatal characters in five tree ferns species (Cyathea fulva, C. divergens, C. myosuroides, Alsophila firma and Gymnosphaera salvinii) distributed along an elevation gradient in a well-preserved Mexican cloud forest. Variation at the community and species level was assessed using exploratory and multivariate data analysis methods. We wanted to explore if the species abundance is environmentally determined, to determine the degree of variation along the elevation gradient, to test for differences between zones and associations with elevation, humidity and soil nutrients, and to assess contribution of the intra- and interspecific variation to the community response to elevation and soil nutrients. The studied fern community showed strong species turnover along the elevation gradient, with some influence of soil nutrient concentration, supporting environmental determinism. All measured characters displayed variation along the gradient. Stomatal characters (size and density) had significantly less variation than morphometric characters (trunk diameter, stipe length and blade length), but stomatal density also shows interesting intraspecific patterns. In general, patterns within the fern community suggest a strong influence of species identity, especially of species inhabiting the lower edge of the cloud forest, which showed the clearest morphometric and stomatal patterns, associated to contrasting environments rather than to changes in elevation. The coincidence between morphometric and stomatal patterns in this area suggest hydraulic adjustments in response to contrasting environments. Our results provide evidence that tree ferns species respond to environmental changes through adjustments of morphometric plasticity and stomatal density, which is relevant to predict possible responses to variation in environmental conditions resulting from climate change.

-Cyathea caracasana is a common open-habitat tree fern in the Andes of Colombia. In full sun, stem growth rates are high (up to 2 cm/month) and individuals regularly produce spores. However, even the fastest growing ferns are overtopped by woody angiosperms after 10 to 15 years of natural forest regeneration. As individuals are overtopped, C. caracasana produces nearly vertical fronds with long stipes (commonly over 3 m) apparently to place the photosynthetic surface into the canopy. We compared stipe length and blade length and width among individuals growing in open sites and in the understories of two regenerating forests: one with a canopy of 20-25 m, and one with a canopy of 5-8 m. Stipes and blades were shortest in open habitat and longest in the low-canopy forest. Ferns in the high-canopy forest had intermediate measurements. Despite the change in frond length, the number of primary pinnae per-frond did not differ among the habitats sampled. This suggests that elongation cues are received late in the development of the frond. This conclusion is supported by a positive relationship between stipe length and the distance of the fern meristem below the canopy. Because both understory populations show stipe elongation relative to open-hapitat ferns, the cue to elongate is likely a low red/far-red wavelength ratio of the light received by the apical meristem. Extraordinary elongation is probably made possible by extra carbon resources available to low-canopy plants, which still have leaves in full sun. This sense and response mechanism allows individual plants to produce elongated fronds as their apical meristems are overtopped. Functionally, the long-stiped plants remain in full sun even after they are overtopped, thus they "track" their preferred, open habitat. Plant populations respond to environmental variation in several ways. When the environment fluctuates infrequently relative to the life span of individuals, adaptive segregation may produce differential response to environmental cues among separate populations. Consider variation in light environment. Sunadapted populations of Impatiens capensis L. showed enhanced growth in response to changes in the ratio of red (600-700 nm) to far-red (700-850 nm) light relative to shade-adapted populations (Dudley and Schmitt, 1995). Similar sun/shade segregation in growth response to red/far-red (R/FR) has been observed in many angiosperm species in open (as compared to understory) communities (Morgan and Smith, 1979). In contrast, when the environment varies frequently relative to the life span of individuals, adaptive segregation cannot occur and individuals must rely on morphological and physiological flexibility (plasticity) (Thompson, 1991; Sultan, 1993; Ackerly and Bazzaz, 1995; Arens, 1997). In such cases, plants may change form or physiology to suit new conditions, for example switching from sun-leaf to shade-leaf anatomy (Arens, 1997). Alternatively, individuals "track" or follow their preferred habitat as it moves. Conventionally, habitat-tracking in plants has been applied to intergenerational migration (Davis et al., 1986; Webb, 1987; Davis and SaThis content downloaded from 157.55.39.128 on Mon, 18 Jul 2016 03:58:47 UTC All use subject to http://about.jstor.org/terms AMERICAN FERN JOURNAL: VOLUME 90 NUMBER 1 (2000)

-We present the first cladistic analysis of extant ferns based on morphological characters. Our data set consisted of 77 vegetative and reproductive morphological/anatomical characters recorded on a broad sampling of 50 extant pteridophyte taxa, with representatives of all major fern groups, and one seed plant (Cycas). An annotated list of both retained and excluded morphological characters is presented. Results from the morphological analysis are compared with an independent analysis of rbcL data carried out here for the same set of pteridophyte taxa. Finally, we analyze a combined (morphological and molecular) data set. All three data sets were analyzed using maximum parsimony. N o separate sets of analyses using different taxon combinations were conducted on each of the three data sets. Analysis 1 focused on phylogenetic relationships of ferns only (Filicopsida, Botrychium, and Angiopteris), using Cycas as an outgroup representative from the seed plants. Analysis 2 focused on phylogenetic relationships of pteridophytes (Filicopsida, Angiopteris, Botrychium, Equisetum, Psilotum), using Lycopodium as the outgroup. In both sets of analyses, the combined data set provided the most robustly supported hypothesis of relationships. Results from the combined data set in Analysis 1 provided strong bootstrap support for the monophyly of the following clades: leptosporangiate ferns (with Osmunda as the most basal leptosporangiate fern], heterosporous ferns, Cheiropleuria-Dipteris, Diplopterygium-Stromafopteris, tree ferns, schizaeoid ferns, pteridoid ferns, and a large clade consisting of a derived group of leptosporangiate ferns that excludes dennstaedtioids and pteridoids. Various smaller clades within some of these larger clades also have strong support. The dennstaedtioid ferns are paraphyletic. We use the results of the combined data set in Analysis 1to examine character evolution within the leptosporangiate ferns. Results from the combined data set in Analysis 2 indicated robust support for essentially the same fern clades as the combined data set in Analysis 1.In both Analyses 1 and 2, bootstrap support for the leptosporangiate fern clade is much greater using the combined data set than when either the morphological or, particularly, the molecular data set is analyzed separately. Relationships among major groups of pteridophytes at the base of the tree (Botrychium, Angiopteris, Psilotum, Equisetum, Lycopodium) were poorly supported by the combined data in Analysis 2, except for a weak association between Botrychium and Psilotum. We are convinced from this study of the value of using both molecular and morphological data sets in combination as well as separately. A synthetic approach that integrates paleobotanical and neobotanical data will be of greatest interest in further elucidating the phylogenetic relationships of pteridophytes. Our understanding of the phylogeny of pteridophytes has lagged behind the considerable progress made recently in clarifying the phylogenetic relationships of other green plants, especially seed plants (Crane, 1985a, 1985b; Doyle Present address: Department of Botany, Field Museum of Natural History, Roosevelt Rd. at Lakeshore Dr., Chicago, IL 60605. 206 AMERICAN FERN JOURNAL: VOLUME 85 NUMBER 4 (1995) and Donoghue, 1986a, 1986b, 1992; Doyle et al., 1994; Loconte and Stevenson, 1990, 1991; Nixon et al., 1994; Rothwell and Serbet, 1994). Often-cited reasons for this discrepancy are that ferns have, relatively speaking, far fewer morphological characters, and that determining homologous character states, particularly when dealing with organisms with such a long geological record, is not feasible. These arguments have become less persuasive since the publication of a number of comprehensive studies on bryophytes and green algae and their relationships to tracheophytes (Garbary et al., 1993; Graham et al., 1991; Mishler and Churchill, 1984, 1985; Mishler et al., 1994). An overview of extant tracheophyte relationships based on recent analyses of green plant phylogeny is shown in Figure 1, indicating major clades that are resolved and areas of greatest uncertainty (unresolved polychotomies). Although numerous phylogenetic studies have been devoted to the seed plants (spermatophytes), higher-level relationships among some of the major extant lines (cycads, Ginkgo, conifers, gnetales, angiosperms) still are not resolved convincingly (Doyle et al., 1994). For example, the position of the cycads as the most basal group in the spermatophytes is supported by Crane (1985b), Loconte and Stevenson (1990), and Nixon et al. (1994), whereas Ginkgo is the most basal spermatophyte in the analysis by Rothwell and Serbet (1994). Other authors have obtained still different arrangements. Within tracheophytes, relationships among pteridophytes are the least understood (Kenrick and Crane, 1991; Nayar, 1970; Rothwell, 1994). The major clades of extant pteridophytes are: lycopodiophytes (Lycopodiaceae, Selaginellaceae, Isoetaceae); psilotophytes (Psilotum, Tmesipteris); equisetophytes (Equisetum); and ferns (Fig. 1).Ferns comprise three classes: the Ophioglossopsida and Marattiopsida (eusporangiate ferns), and the Filicopsida (leptosporangiate ferns). It has been hypothesized that the psilotophytes are the most basal lineage of extant pteridophytes, and indeed of all extant tracheophytes (Bremer, 1985; Bremer et al., 1987; Parenti, 1980; Pichi Sermolli, 1959). However, more recent evidence supports the placement of the lycopodiophytes at the base of the extant tracheophyte clade (DiMichele and Skog, 1992; Donoghue, 1994; Kenrick and Crane, 1991; Raubeson and Jansen, 1992). Contemporary estimates of higher-level relationships in ferns are mostly intuitive and founded largely on the phenetic concept of overall similarity of morphological/anatomical characters. These characters most often include the sorus and its associated structures (sporangia, indusia, spores), leaf architecture and venation, rhizomes, stipes, and chromosome numbers. In 1969, Wagner attempted a more objective approach to resolving fern phylogeny by applying his "ground plantdivergence method" to homosporous ferns. This method consisted of first inferring the primitive and advanced states of various characters based on the assumption that the commonest character state is usually also that which is primitive. How these states were correlated was then determined so as to organize the taxa graphically in an evolutionary pattern (Wagner, 1969, 1980). A slightly modified version of Wagner's scheme of evolutionary relationships is still presented in morphology and evolution textbooks (e.g., Gifford and Foster, 1988). Smith (1995) reviewed modern ideas on PRYER ET AL.: FERN PHYLOGENY BASED ON MORPHOLOGY AND rbcL SEQUENCES 207

Hybridization is common in many ferns and has been a significant factor in fern evolution and speciation. However, hybrids are rare between the approximately 30 species of Dicksonia tree ferns world-wide, and none are well documented. In this study we examine the relationship of a newly-discovered Dicksonia tree fern from Whirinaki, New Zealand, which does not fit the current taxonomy of the three species currently recognized in New Zealand. Our microsatellite genotyping and ddRAD-seq data indicate these plants are F1 hybrids that have formed multiple times between D. fibrosa and D. lanata subsp. lanata. The Whirinaki plants have intermediate morphology between D. fibrosa and D. lanata subsp. lanata and their malformed spores are consistent with a hybrid origin. The Whirinaki plants–Dicksonia fibrosa × D. lanata subsp. lanata–are an example of hybridization between distantly related fern lineages, with the two parent species estimated to have diverged 55–25 mya. Our chloroplast sequencing indicates asymmetric chloroplast inheritance in the Whirinaki morphology with D. lanata subsp. lanata always contributing the chloroplast genome.

… In contrast to a primitive cauline anatomy, the new fern shows an advanced level of morphological organization with branching stems bearing leaf members (phyllophores) and roots, …

… The tree fern Cyathea caracasana is used as a living model … tree ferns and some Paleozoic free-standing arborescent pteridosperms. A variety of leaf anatomical and morphological …

Variation in species richness across regions and between different groups of organisms is a major feature of evolution. Several factors have been proposed to explain these differences, including heterogeneity in the rates of species diversification and the age of clades. It has been frequently assumed that rapid rates of diversification are coupled to high rates of ecological and morphological evolution, leading to a prediction that remains poorly explored for most species: the positive association between ecological niche divergence, morphological evolution and species diversification. We combined a time-calibrated phylogeny with distribution, ecological and body size data for scaly tree ferns (Cyatheaceae) to test whether rates of species diversification are predicted by the rates at which clades have evolved distinct ecological niches and body sizes. We found that rates of species diversification are positively correlated with rates of ecological and morphological evolution, with rapidly diversifying clades also showing rapidly evolving ecological niches and body sizes. Our results show that rapid diversification of scaly tree ferns is associated with the evolution of species with comparable morphologies that diversified into similar, yet distinct, environments. This suggests parallel evolutionary pathways opening in different tropical regions whenever ecological and geographical opportunities arise. Accordingly, rates of ecological niche and body size evolution are relevant to explain the current patterns of species richness in this ‘ancient’ fern lineage across the tropics.

… In this context, studies of fern biogeography have focused on the dispersal capability of spores to … Global biogeography of scaly tree ferns (Cyatheaceae): evidence for Gondwanan …

… type spores are present in other living species of Cyatheaceae, as not all have as yet been … appear to be directly related to the biogeographic history of Cnemidaria spores discussed in …

The species allied to Cyathea platylepis are recognized as a distinct group among Neotropical Cyathea, and are regarded as closest relatives to the few Paleotropical members of the genus in the strict sense. All species have slender trunks that shed old petioles cleanly, inermous petioles with relatively few, ovate-lanceolate brown scales, relatively strongly dissected (to tripinnate-pinnatifid) laminae, and proximally positioned sori with hemitelioid indusia. Most of the remaining Neotropical species referred to as the C. multiflora-group fall into two distinct groups. The group of Cyathea vilhelmii differs from the C. platylepis group chiefly in having dense petiolar scurf, and bicolorous or concolorous white petiole scales. These species occur at high elevations in the Andes and Central America. The group of Cyathea multiflora is heterogeneous in habit and laminar dissection but is characterized by a medial to marginal position of the sori and a preference of lower montane and lowland forests. It includes the species allied to C. multiflora and C. andina, as well as some species formerly regarded as belonging to Sphaeropteris. All groups may have to include species that either have different types of indusia or lack them in order to represent natural taxa. Five names have been reinstated in the course of this study and replace commonly used names: Cyathea austroamericana (= C. multiflora pro parte), C. boryana (= C. andina pro parte), C. leucolepismata (= C. amazonica), C. lindigii (= C. multiflora pro parte), C. traillii (= C. reginae), and C. vilhelmii (= C. heliophila). Cyathea vaupensis is recognized at species level. A new name is chosen for Cyathea panamensis = Cyathea rojasiana. Keys to all species are included.

Aim We investigated changes in distribution of cloud forests during the last 130 kyr, and tested whether these changes explain the spatial patterns of genetic diversity of the tree fern …

… in scaly tree ferns (Cyatheaceae). Nevertheless, recent … was used to reconstruct their biogeographical range history. … Our biogeographical study suggests that the four endemics …

… Most stark is the finding that most alien species are from the largest family, Cyatheaceae. This family has over 700 species and a native range that encompasses most tropical, …

Based on extensive field surveys and studies of numerous herbarium collections, a taxonomic revision on the tree ferns (Cyatheaceae) from Hainan Island, South China is made. Some …

. We present an update to our knowledge of the taxonomically challenging Cyathea multiflora-group. Several taxa can be reinstated and newly described thanks to extensive field …

) with habitat fragmentation. Analysis of niche dynamics under future climate change indicates that this family exhibits a conservative response strategy. MESS analysis revealed climate anomaly zones significantly overlapping core habitats. Model extrapolation validated these patterns, identifying southern regions as conservation priorities. The findings suggest prioritizing conservation networks centered on climate refugia in central Taiwan, central Hainan, and southern China, coupled with microclimate management and germplasm conservation to safeguard this ancient family.

… However, representative specimens of Cyatheaceae should include a part of the petiole with … both are endemic to northern Venezuela but occur in two well-separated biogeographic …

… Cyatheaceae in the last 50 years that recognise one (Cyathea) to many (eg Alsophila, … Therefore, regeneration and conservation status of the threatened Cyathea spp. in the Seijosha …

… In relation to temperature, the result of this study reinforces that the speed and final germination percentage of Cyatheaceae are generally higher at median temperatures (Pérez-Garcia …

Cyatheaceae, assigned to the fern order Eufilicales, is one of the most ancient extant lineages of arborescent tree-ferns and is widely distributed across tropical, subtropical, and parts of the temperate Southern Hemisphere. This group is ecologically, scientifically, and medicinally valuable. It serves as a critical bioindicator of forest ecosystem stability, provides an ideal model system for investigating adaptive evolution and stress response mechanisms in plants, and produces secondary metabolites with promising pharmaceutical applications. Recent advances in modern molecular biology have markedly promoted omics-based research on the family. Here, we systematically review multi-omics achievements—genomics, transcriptomics, and related fields—with emphasis on how sequencing technologies and functional genes have elucidated genetic diversity, cryptic lineage divergence, and adaptive evolutionary mechanisms in response to biotic and abiotic stressors, including climate change, habitat fragmentation, and interspecific competition. We summarize current conservation applications, highlight core problems such as taxonomic and geographical sampling bias and insufficient multi-omics integration, and propose future research directions so as to provide a scientific basis for the systematic conservation, sustainable utilization, and in-depth study of the genetic resources of Cyatheaceae under increasing environmental pressures.

… Effective conservation strategies are therefore to be formulated to save C. gigantea from the … Distribution of tree ferns (Cyatheaceae) across the successional mosaic in an Andean cloud …

… to the genus Cyathea of Cyatheaceae and 1 belongs to the … distribution, ecology and conservation status of the tree ferns … The tree fern family Cyatheaceae are well known for their …

Tree ferns are a remarkable group among the lycophytes and ferns. Geographical isolation is suggested as one of the main reasons for local endemism of tree ferns and the island of Sri Lanka has been identified as one of the best demonstration sites to observe this phenomenon. Despite its small size, Sri Lanka has a rich diversity and one of the highest levels of endemism of tree ferns in Asia. Their diversity here is considered as an unique and important gene pool in the world. The present eco-spatial survey is to study the diversity and ecology of tree ferns in Sri Lanka. The study identified nine tree fern species including one new record of an adventive species. The species are Cyathea hookeri , C. sinuata , C. sledgei , C. srilankensis , C. walkerae , C. crinita , C. gigantea , C. australis and Dicksonia antarctica . Of these, the first five species are endemic to Sri Lanka . Dicksonia antarctica and Cyathea australis are exotic and naturalised in forest clearings in Piduruthalagala forest. Cyathea hookeri , C. sinuata , C. sledgei and C. srilankensis are confined to limited populations in lowland rainforests (62-550 m). Cyathea walkerae is distributed in a wide elevational range throughout the wet zone (30-2,300 m), whereas C. crinita shows a restricted distribution pattern at a high altitude range (1,800-2,400 m). In this study C. gigantea was recorded additionally from lowland rain forests, though it was previously reported to be confined to submontane and montane ecosystems. The results of this study provide baseline information on the distributional ecology of Sri Lankan Cyathea species. It will be useful to assess their current conservation status and to formulate conservation guidelines for these remarkable and spectacular ferns so characteristic to Sri Lanka.

… This protective measure is necessary because tree fern trunks of Cyatheaceae and Dicksoniaceae with their fibrous root mantle are locally used for making special flowerpots and …

Introduction: Tree ferns are significant components of temperate, tropical and subtropical forests, contributing to shape complex forest stand structures. Objectives: 1) to describe the population structure of Cyathea costaricensis in a remnant cloud forest of West-central Mexico; 2) to characterize and relate the floristic composition and the structure of the most important tree species associated to the C. costaricensis population and; 3) to describe the environment where C. costaricensis occurs. Methods: We estimated the Importance Value Index (IVI) to select the most important canopy-dominant species associated to C. costaricensis; we constructed height and Diameter at Breast Height (DBH) frequency distributions for those selected species according to IVI as well as for C. costaricensis population; we computed the asymmetry of the frequency distributions through the coefficient of skewness and the probability density function via the Kernel density estimation. We tested for differences between canopy-dominant tree species and C. costaricensis population structure by the non-parametric Wilcoxon rank sum test. Results: C. costaricensis individuals presented the smallest heights and intermediate DBH sizes as compared with the canopy-dominant species, with statistically significant differences for height but not for DBH according to the Wilcoxon test. Most of the tree fern individuals were located in uneven terrains and over the base slope of the terrain; canopy openness and Total Radiation Under the Canopy values were similar to those reported for Cyathea species elsewhere. Conclusions: We confirm the hypothesis of comparable structure between the canopy-dominant species and the C. costaricensis population only for DBH; on the contrary, for trunk height, there were statistically significant differences; the small heights of C. costaricensis suggest their coexistence in the understory through sheltering from the taller canopy-dominants. Mostly all individuals of C. costaricensis were confined to local environmental conditions, particularly to physiography.

… Much of this research has been generated as a result of the requirement for research and monitoring of tree ferns as part of tree fern management plans of the southern states: Tasmania…

… To produce age–frequency distributions for the individual species of tree fern, we calculated the time taken for a tree to grow from 135 cm in height to the observed height, using …

… of two common species of tree fern, Dicksonia antarctica and … Sixteen percent of the 2391 tree-ferns monitored remained … Low tree-fern survival is likely to result in declines in the …

ABSTRACT Tree ferns are slow-growing and long-lived components of temperate forests; however, these characteristics make determining size-age and population dynamics through mensuration approaches problematic while dendroecological approaches cannot be used. In this study, we use radiocarbon (14C) dating of Cyathea australis and Dicksonia antarctica to (1) determine their age-to-size relationships, (2) reconstruct the age distribution of tree fern species, and (3) test if predicted ages align with the ages of the co-occurring tree community and observed disturbance history. We used the best age-size models to reconstruct the population structure of tree ferns sampled in five paired rainforest and old-growth eucalypt stands and compared these to the age structure of co-occurring tree species. The species had similar growth allometry; however, C. australis grew four times faster than D. antarctica. The age class structures of tree ferns were congruent with the associated tree species and reflected known fire history and snowfall events in the region. Tree fern abundance increased with increasing time-since-fire and post canopy disturbance. The study demonstrates that 14C dating of tree ferns provides a means of investigating tree fern demographics and the role of disturbance in shaping their population structure in forests of southeast Australia.

Sphaeropteris lepifera, a rare and endangered species belonging to the family Cyatheaceae, is often referred to as a “living fossil” and possesses significant ornamental value. This study investigated the survival status of four wild S. lepifera populations, with a focus on the impact of different canopy densities on the growth of Sphaeropteris lepifera plantlets. Moreover, an ensemble model incorporating ten algorithms was developed to assess the potential suitable distribution ranges of S. lepifera current and future climate conditions. The results indicate the wild population of S. lepifera exhibits a declining trend, which poses a very high risk of extinction. Variations in canopy density have significantly altered the understory light environment, leading to disorganization in the chloroplast grana lamellae structure of S. lepifera under C1 (< 30%) canopy density. This disorganization results in damage to photosystem II, blockage of electron transfer, increased expression of chloroplast genes, and ultimately yellowing of the leaves, which contributes to overall slow plant growth. Predictions from the ensemble model suggest that current suitable habitats of S. lepifera are located along the coastlines of Zhejiang, Fujian, and Guangdong provinces, as well as in Hainan and Taiwan, identified as preferred areas for reintroduction into the wild. The overall suitable distribution of S. lepifera is projected to shift northward, with an increase in total area under future climate conditions, except the extreme climatic conditions (SSP585, 2100). However, this expansion of the suitable habitat does not change the endangered status of S. lepifera, due to the factors such as interspecific competition, man-made interference, and species dispersal capabilities, etc. Therefore, mitigation efforts, including human interventions such as the reintroduction of plantlets, spore propagation, and artificial management of suitable areas, remain essential.

… demography of tree fern Cyathea spinulosa Wall. ex Hook at a 40 m × 100 m plot with 163 tree ferns in lowland of … They were periodically monitored (16 times) until March 2000. At each …

Tree ferns are ubiquitous in New Zealand forests, but there is limited knowledge of their role in urban plant communities and potential use in restoration. We assessed sixteen sites by measuring 200 m2 plots to investigate how tree ferns influence vascular plant composition in Hamilton, North Island, New Zealand. The sixteen plots were assigned to four site type combinations based on restoration status (restored or unrestored) and tree fern presence, each with four plots. Average native plant species richness was higher at sites with tree ferns (36 ± 16; S = 68) than at sites without (19 ± 14; S = 41), with more diverse ground fern and epiphyte assemblages. Higher native plant richness at restored sites (34 ± 18; S = 62) compared to unrestored sites (20 ± 14, S = 44) was partially attributed to increased plant abundances. Multivariate analyses revealed differences in plant community composition among our site types. Angiosperms and conifers were less prevalent in plots with tree ferns, suggesting competitive relationships among these groups. However, tree ferns were associated with some shade-tolerant trees, such as Schefflera digitata J.R.Forst. & G.Forst. Indicator species of sites with tree ferns were mainly ground ferns and epiphytes (e.g., Blechnum parrisiae Christenh. and Trichomanes venosum R.Br.), whereas species with high fidelity to sites without tree ferns were pioneer trees and shrubs (e.g., Pittosporum eugenioides A.Cunn.). Community structure analyses revealed that total basal areas were highest at unrestored sites with tree ferns, but restored sites exhibited more diverse tree communities. Environmental predictors that correlated significantly with the compositional differences among our site types were tree fern basal area and restoration age. Our results highlight the need to reconsider the potential of tree ferns in current restoration practice. Tree ferns were found to augment native plant diversity in our study, indicating their potential to enhance urban ecological restoration projects in New Zealand.

… ecological consequences of deer browsing on tree fern populations. These effects may be … to wet forest systems in their research, monitoring, and management practice. In particular, …

Praptosuwiryo TNg, Pribadi DO, Puspitaningtyas DM, Hartini S (2011) Inventorying the tree fern Genus Cibotium of Sumatra:Ecology, population size and distribution in North Sumatra. Biodiversitas 12: 204-211. Cibotium is one tree fern belongs to the family Cibotiaceae which is easily differentiated from the other genus by the long slender golden yellowish-brown smooth hairs covered its rhizome and basal stipe with marginal sori at the ends of veins protected by two indusia forming a small cup round the receptacle of the sorus. It has been recognized as material for both traditional and modern medicines in China, Europe, Japan and Southeast Asia. Population of Cibotium species in several countries has decreased rapidly because of over exploitation and there is no artificial cultivation until now. The aims of this study were: (i) To re-inventory the species of Cibotiun in North Sumatra, (ii) to record the ecology and distribution of each species, and (iii) to assess the population size of each species. Field study was carried out by using random search with belt transect. Two species were recorded, namely C. arachnoideum dan C. barometz. The geographical distribution of the two species in North Sumatra is presented. Cibotium is commonly growing terrestrially on opened or rather opened areas in secondary forest and primary forest at hills or lower mountains with a relatively high humidity at 30-90Âo slopes. C. arachnoideum has a strict distribution and only found at 1740-1770 m a.s.l. in primary forest, whereas C. barometz has a broad distribution in secondary forest at elevation range from 650-1200 m.Key words: Cibotium, ecology, distribution, tree fern, Sumatr

… of the invasive tree fern was 15 cm compared to 2 to 3 cm for the native tree ferns. The leaf mass … more fertile fronds per month than the native tree ferns. These differences in life history …

… plants in Cyatheaceae have never been reported. Here, the present work is related to Alsophila costularis, a specie of Cyatheaceae. We establish an in vitro propagation protocol of A. …

Abstract Cyathea corcovadensis and Cyathea phalerata are tree ferns native to Brazil, endangered in the state of Rio Grande do Sul. Spore germination and gametophyte development in media with different nutrient formulations and activated charcoal were evaluated, aiming to develop a process for obtaining plants of the two species. Spores were sown in four semi-solid culture media: Meyer, Dyer, MS with 50% and MS with 25% of the original macronutrient concentration. For each medium, 10 replicates were carried out (flasks with 5 mg of spores/30 mL of medium), with and without 1% activated charcoal, respectively. Spore germination and gametophytic development (laminar and cordate stages) were quantified at 30, 60 and 90 days of culture. Cyathea corcovadensis and C. phalerata germinated and developed gametophytes in all media. For both species, the highest percentages of germination and cordate gametophytes (more advanced development stage) were recorded in Meyer medium without activated charcoal, which has higher concentrations of macronutrients and no micronutrients compared to the other evaluated media. We recommend cultivating the plants in Meyer medium for greater gametophytic development and subsequent sporophyte obtention, as a biotechnological tool for C. corcovadensis and C. phalerata conservation and for environmental restoration and enrichment using these tree ferns.

The influence of the temperature and different light qualities emitted by light-emitting diodes (LEDs) and fluorescent lamps (Fl) on the micropropagation of the tree fern Cyathea delgadii was evaluated. The most efficient somatic embryo production was obtained on internode explants at 22 °C. The optimal temperature range for obtaining well-developed plants was 24–28 °C. This stimulated the elongation and development of the first leaf and the formation of the next leaf and roots primordia. Temperatures lower than 24 °C and higher than 28 °C inhibited the formation of young sporophyte organs and delayed their development. The RBUV (35% red, 15% blue, and 50% UV) and B (100% blue) lights and Fl light were beneficial for the sporophyte production on internode explants. However, plants obtained under RBUV light were undeveloped. The white LED light stimulated the number of explants capable of gametophyte production and development. The RB light (70% red and 30% blue) enhanced the number of roots of newly-formed plants. Most of the LED lights tested had a good impact on root elongation compared to Fl light and constant darkness. The R light (100% red) benefits leaf development and elongation. Research shows that temperature and LED lightning play a significant role in the process of morphogenesis in C. delgadii, significantly affecting the embryogenic competence of somatic cells and the development of sporophytes. A wide range of temperatures and light qualities have been investigated for optimizing the efficiency of in vitro morphogenesis of the tree fern Cyathea delgadii.

… Our study focused on providing basic information to allow the ex situ conservation of endangered species of the family Cyatheaceae. Tree ferns are usually propagated ex situ through …

Cyathea latebrosa is one of the lowland tree fern species found in Peninsular Malaysia. This fern species is highly demanded in ornamental landscaping. The in vitro cultures are an important tool for propagation which may contribute toward the reduction of over-exploitation. To overcome these problems, an effective spore surface disinfection protocol is crucial to allow the germination stage to be carried out. This studied had carried out three types of methods which are the packet method (PM), centrifuged method (CM), and soak method (SM) with difference percent of concentration (0, 0.1, 0.5, 1.0, 10 & 30) Mercury Chloride (HgCl2) and Sodium hypochlorite (NaOCl). In contrast, the method and concentration of disinfection affect germination. Our results showed that the soak method in both types of disinfection is a significant difference due to statistical analysis (MANOVA) which gives a positive effect on the germination of the spore. This method is efficient for sterilizing which spore loss is kept to a minimum and has a higher rate of germination (HgCl2-90% & NaOCl-80%). The optimum concentration of HgCl2 was 0.1%, then followed by 0.5% and 1.0%, while for NaOCl was 30%, 20%, and 10%.

… Fern gametophytes, derived from in vitro cultures, are a useful source of germplasm for ex situ … Integrating in vitro methods for propagating and preserving endangered plants. 11th …

This study was undertaken to identify methods of mass multiplication for five ornamental, economically important ferns (Nephrolepis biserrata (Sw.) Schott., N. cordifolia cv. ‘‘duffii’’ (L.) Presl., N. exaltata cv. bostoniensis (L.) Schott., Pteris vittata L., and Cyclosorus dentatus Link.,) and three threatened ferns, namely, Cyathea spinulosa Wall. ex. Hook, Pityrogramma calomelanos (L.) Link., and Microsorum punctatum (L.) Schott., through in vitro techniques. Collections were made from different biodiversity zones of India including Northeast Himalayas, Kumaon Himalayas, and Western Ghat and successfully introduced and grown in a fern-house. Aseptic cultures were raised at the morphogenic level of callus, axillary shoot, multiple shoot, and rooted plants. An optimized medium is described for each fern species. Plantlets were also produced from spore culture of Cyathea spinulosa and successfully hardened under fern house conditions.

In order to successfully establish themselves in their natural environment, ferns need habitats with abiotic conditions that are suitable for spore germination and gametophyte development. The objective of this study was to assess the influence of abiotic factors on the initial development of Cyathea phalerata cultivated in vitro. Spore germination and gametophyte development were assessed under varying conditions of surface sterilization, pH, temperature and photoperiod. Exogenous contamination was eliminated by sterilizing spores with 2.5 % NaClO for 15 min and sowing them into a culture medium supplemented with nystatin. Spores germinated at all pHs tested. Gametophytic development was faster in acidic pHs. Cultures at 25 °C exhibited the highest percentages of germination and laminar gametophytes. The species produced its highest percentages of gametophytes in cultures with photoperiods between 6 and 18 h. The optimal abiotic conditions found here for in vitro development of C. phalerata are similar to those found in its natural habitat. The southern limit of this species to north of the 30th parallel in Rio Grande do Sul, Brazil, may be because further south spores do not encounter the ideal combined conditions of temperature, pH and photoperiod determined in the laboratory.

… Generally, two methods of fern propagation have been developed: sexually and asexually by offshoots. The first one consists in sterile spores germination and consecutive culture of …

… This study systematically evaluates the allometric characteristics of tree ferns using 463 individuals of the extant tree fern Cyathea (Cyatheaceae) from the Leshan area of Sichuan …

Phenological studies are fundamental to our understanding of how the environment can influence plant growth and reproductive processes. Environmental triggers of fern phenology are poorly known. We investigated the leaf phenological traits of the tree fern Cyathea praecincta (Kunze) Domin in a Brazilian lowland tropical forest with a short dry season. We monitored 47 plants over an 18-month period, measuring leaf production, leaf fertility, leaf mortality and the relation of these variables with rainfall and temperature. Data on leaf expansion and lifespan were also presented. Full leaf expansion in C. praecincta took up to 3 months. The production of sterile and fertile leaves showed dissimilar interactions with climate, a common pattern among most tree ferns studied worldwide. Whereas production of sterile leaves of C. praecincta was not influenced by climatic variability, leaf fertility was driven by increasing rainfall. Some fertile plants (30%) produced exclusively fertile leaves and attained full maturity, playing a key role in the maintenance and growth of the population. The estimated leaf lifespan was 17.9 ± 5.89 months. The finding that leaf mortality was driven by decreasing rainfall is in contrast with most tree ferns, which are not influenced by climate. None of the phenological variables was influenced by temperature. We demonstrated that rainfall plays a crucial role on leaf fertility and leaf mortality of C. praecincta in a tropical forest remnant with a short dry season and inversely related rainfall and temperature.

Cyathea corcovadensis (Raddi) Domin occurs in northeastern, southeastern and southern Brazil, being widely distributed in the last. This was a three-year study, conducted from August 2008 to July 2011, in which we evaluated C. corcovadensis in a subtropical forest in southern Brazil. For the first year (August 2008 to July 2009), we monitored 30 plants on a monthly basis in order to analyze phenological events (vegetative and reproductive) and caudex growth. We also estimated the ages of the plants. Except in June and July of 2009, monthly leaf emergence and senescence were continuous and irregular, which prevented total leaf abscission, during that first year. Leaf emergence, senescence and fertility correlated with photoperiod, temperature and plant height, whereas rainfall was not a good predictor of C. corcovadensis phenophase. Within the forest fragment studied, the high proportion of fertile individuals (63.3%) indicated that the population has the potential to increase in size. The mean annual caudex growth rate was 4.66-8.23 cm and was statistically equivalent among the three years evaluated. The number of leaves per plant remained stable throughout the study period. Among plants that were 4 m tall, the mean estimated age was 60.3 years when calculated on the basis of overall height and mean annual growth rate, compared with only 46.9 years when calculated on the basis of the number of total leaf scars or petiole remains on the caudex and mean annual leaf production.

Approximately eleven species of tree ferns (Cyatheaceae, Dicksonia, and Lophosoria) occur in the cloud forest of La Reserva Natural La Planada, Nariño, Colombia. We used 500 m 2 (…

Abstract Spores of species of Sphaeropteris genus from America were studied with TEM and SEM. Six species were quoted as growing in America (cf. Tryon, 1971; Windisch, 1977): Sphaeropteris brunei (Christ) Tryon, Sphaeropteris cuatrecasacansii Tryon, Sphaeropteris gardneri (Hook.) Tryon, Sphaeropteris horrida (Liebm.) Tryon, Sphaeropteris insignis (D. C. Eaton) Tryon and Sphaeropteris quindiuensis (Karst.) Tryon. The aims are to characterize the species through their spore morphology and sporoderm ultrastructure. Based on these results it speculates about the relationships of these taxa within the family Cyatheaceae. It was find out with SEM, three kinds of surfaces can be recognized. It was find out with TEM that the exospore and perispore have two layers. The perispore is composed of an inner layer with three strata and the outer layer has two strata. The palynological characteristics were important in the identification of a natural taxonomic group.

-Sphaeropteris lepifera is one of the largest tree ferns in Taiwan. On average, it produces 50.7 sporangia per sorus, and 64 spores per sporangium. Spore germination, after 2 years of storage at 4?C was over 95%. The pattern of spore germination was "Cyathea-type", and the gametophytes exhibited mainly Drynaria-type development with occasional Adiantum-type development. Typical gametophytes were heart-shaped but had the potential to elongate and become elliptical. Multicellular hairs on the dorsal and ventral surfaces of the midrib cushion increased in size and changed shape with age. They were usually uniseriate when young, and became multiseriate with age. Gametophytes initiated antheridia about 1 month after spores were sown, and did not become hermaphrodites until 7 weeks later. During ontogeny, the gametangial sequence was from the male to hermaphroditic. Antheridia formed on the wings of the ventral and dorsal surfaces of gametophytes. The wall of each antheridium was composed of 5 cells. Archegonia appeared on the cushion of the ventral surface of gametophytes. Some gametophytes initiated clone-formation through vegetative regeneration. When sufficient water was provided, young sporophytes began to appear 12 weeks after spores were sown. The first fronds were midribless. The uniseriate, multicellular hairs on young sporophytes were similar to those on gametophytes. Gametophyte morphology, including mature forms, spore germination, and types of early development, trichomes, and gametangia, have been used to characterize fern taxa (Stokey, 1918, 1930; Atkinson and Stokey, 1964; Nayar and Kaur, 1971; Atkinson, 1973). These characteristics provide information relevant to fern phylogeny (e.g., Nayar and Kaur, 1971) and the ecology and reproductive biology of different species (Chiou and Farrar, 1997a, b; Chiou et al., 1998; Masuyama, 1975a, b, 1979). In the Cyatheaceae, spore germination is Cyathea-type and gametophyte development is Adiantum-type or nearly Drynaria-type (Nayar and Kaur, 1971). Gametophytes are long-lived (2-6 years) and tend to elongate slightly with age. The multicellular, bristle-like hairs that appear on gametophytes in this family indicate the Cyathaceae is phylogenetically close to the Loxsomaceae (Atkinson and Stokey, 1964). Antheridia and archegonia typically occur on the same gametophytes, with some vigorous gametophytes being strictly archegonial (Stokey, 1930). Apogamy was reported in some species in the Cyatheaceae 1 Corresponding author. This content downloaded from 157.55.39.231 on Wed, 05 Oct 2016 04:13:14 UTC All use subject to http://about.jstor.org/terms AMERICAN FERN JOURNAL: VOLUME 90 NUMBER 4 (2000) TABLE 1. Spore sources, usage, culture medium and storage period.

… This is a small group of species allied to Sphaeropteris horrida (Cyathea prin ceps). The relation of the Sphaeropteris horrida group to species such as Sphaeropteris medullaris of New …

The spore morphology and wall ultrastructure of Sphaeropteris gardneri (Hook.) R.M. Tryon from Brazil were analyzed with LM, SEM and TEM. The spores are trilete with an ornamentation formed of short low ridges with spines in their margins. The exospore is 2.5microm thick, two- layered in section and single or branched channels are present. The perispore is 1.2microm thick and two-layered. The inner layer has three strata: the inner stratum is formed of a network of branched and fused threads, the middle stratum has threads with a radial orientation and in the outer stratum thin, dark fibres are immersed in a less dense contrasted matrix. The outer layer of the perispore is the one that forms the echinate-ridges and is constituted of threads arranged in a compact way. Globules of different sizes are observed on the surface. The differences found in the perispore ornamentation and ultrastructure in Alsophila, which was previously studied, and those of Sphaeropteris, show a tendency to wall complexity.

Tryon (1970) revised the classification of the family Cyatheaceae and recognized six genera and three principal evolutionary lines among the squamate genera. Sphaeropteris with its undifferentiated (conform) scales represents an evolutionary line and occurs at the base of the squamate genera, while Cnemidaria with its marginate scales is found at the top of another evolutionary line. Sphaeropteris supposably contains elements allied to the other two major evolutionary groups in the family (Tryon & Tryon, 1982). On the basis of scale characters, Sphaeropteris subgenus Sphaeropteris is related to Alsophila and subgenus Sclephropteris is allied with Trichipteris, Cyathea and Cnemidaria. Holttum and Edwards (1983) believe that this latter alliance (together with certain species of Tryon's Sphaeropteris) forms a natural group which needs a new subdivision. Holttum (1963, 1964, 1965) also has intensively studied the Cyatheaceae, but recognized only a single genus Cyathea for the same taxa in the family. He subdivided the genus on the basis of characters of the stipe scales and associated characters of indusia, hairs and venation, and felt that the only sharp subdivision within the genus is between the subgenus Sphaeropteris and the subgenus Cyathea (Holttum, 1982; Holttum & Edwards, 1983). His subgenus Sphaeropteris is characterized by peculiar marginal setae on the stipe scales and certain indusial and venation characters, while Tryon (1970) regarded the uniformity of cells of the stipe scales as the most important character for delimiting the genus Sphaeropteris. Although Tryon (1970) promoted subgenus Sphaeropteris to generic rank, Holttum & Edwards (1983) feel that it is not a natural group and contains species that do not belong in the group. Sphaeropteris sensu Tryon is a genus of approximately 120 species found in both the New and Old World. Its distinctive feature is the presence of conform stipe scales with undifferentiated or poorly differentiated cellular construction

… jority of neotropical species of Sphaeropteris, the proposed … Sphaeropteris species comprise the Sphaeropteris horrida group which has clear affinities with paleotropical Sphaeropteris …

In this study, we investigated suitable habitats for the endangered tree fern, Sphaeropteris lepifera (J. Sm. ex Hook.) R.M. Tryon, based on fieldwork, ecological niche modeling, and regression approaches. We combined these data with the characterization of spore germination and gametophytic development in the laboratory to assess the reasons why S. lepifera is endangered and to propose a conservation strategy that focuses on suitable sites for reintroduction and accounts for the ecology and biphasic life cycle of the species. Our methods represent an integration of process- and correlation-based approaches to understanding the distributional patterns of this species, and this combined approach, while uncommonly applied, is a more robust strategy than either approach used in isolation. Our ecological niche models indicated that cold temperature extremes, temperature stability over long- and short-terms, and the seasonality of precipitation were among the most important abiotic environmental factors affecting the distribution of S. lepifera among the variables that we measured. Moreover, distribution of this fern species is also strongly influenced by the timing of development of male and female gametes. Additionally, we observed that slope aspect, specifically south-facing slopes, facilitates more incoming sunlight for mature trees, and simultaneously, provides greater, much-needed shade for fiddleheads on account of the canopy being denser. We believe that our study can provide important guidance on the restoration of S. lepifera in the wild. Specifically, potential restoration areas can be screened for the specific environmental factors that we infer to have a critical impact on the survival of the species.

… tic of the relatively primitive genus Sphaeropteris, in … developed from echinate in Sphaeropteris to striate in Alsophila … its turn, ornamented; and Sphaeropteris has the most prominent …

… 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 …

The ultrastructure of the sporoderm of three genera of the Family Cyatheaceae was studied in detail, with the aim to elucidate its constituent elements. While the perispore of Alsophila and Sphaeropteris is thick and complex, that of Cyathea is reduced and with a different structure; nevertheless, their basic elements seem to be similar. We found that the substructural components are threads with a diameter of 50–100 nm and that each one is composed of an inner channel, around which there are several smaller coiled units. The channels are interconnected and form a complex system, which is continuous within the exospore and in a similar pattern. This network of threads could be related to the transfer of substances between the outer and inner parts of the spores during their development.

-The ontogeny of the sporangia of Sphaeropteris cooperi was studied using cleared whole mounts of sporangia in different stages as well as sori embedded in paraffin and sectioned. The sporangia develop from a single superficial primordial cell that becomes divided into five initials or "segments." Segment 0, located at the level of the surface receptacular cells, does not become subdivided and does not contribute further to the structure of the mature sporangium. Segments I, II, III and IV each become subdivided through a series of divisions to produce the mature sporangia. The four-rowed sporangial stalks are formed from Segment I and part of Segment II, and the capsules develop from a part of Segment II and Segments III and IV. The annulus develops in Segments II and IV. The developmental pattern of the sporangia of Sphaeropteris cooperi is compared to that of the sporangia of higher leptsoporangiate ferns. The most familiar and most frequently illustrated leptosporangia are those of the higher leptosporangiate ferns. The development of the sporangia of the higher leptosporangiate ferns was described in a series of papers (Wilson,1958a, b, 1960) and is now well understood. In the sporangia of the advanced leptosporangiate ferns, as illustrated by species in the Polypodiaceae, Grammitidaceae, and Vittariaceae, it was shown that the stalk and the capsule of the leptosporangium develops from a single epidermal primordial cell that becomes divided into five initials or "segments," rather than from the activity of an apical cell. Each one of these "segments" in turn divides, through a series of divisions to produce the mature sporangium. Segment 0 contributes only to the formation of the stalk; Segment I to a portion of the stalk and part of the proximal face of the capsule; Segment II to the stomial region, the stalk, and to the proximal and distal faces of the capsule; and Segments III and IV to the rest of the annulus and to both the proximal and distal faces of the capsule. Although the stalk may be one-, twoor three-rowed at its base, the capsule is always subtended by a three-rowed stalk. The one-rowed stalk results directly from the horizontal orientation of the first division of the sporangial initial, whereas the twoand three-rowed stalks depend on the orientation of both the first division and also the division that produces Segment I. A review of the history of our knowledge of the nature of the leptosporangium and its development was published in the introduction to the study of the ontogeny of the sporangia of Phlebodium aureum (L.) J. Sm. (Wilson, 1958a). Recent descriptions of sporangial development continue to reproduce the erroneous pattern apparently originated by Campbell (1905) that the sporangial initial produces a three-sided apical cell that cuts off several basal cells to form the stalk until a transverse division stops its activity by cutting off the cap cell. Other accounts are unclear, incomplete and often incorrect. (see Gifford and Foster, 1989; Bold et.al., 1987; Holttum et. al., 1970). No detailed ontogenetic studies have been published since the appearance of the paper on This content downloaded from 207.46.13.149 on Wed, 28 Sep 2016 06:18:20 UTC All use subject to http://about.jstor.org/terms WILSON: SPORANGIAL ONTOGENY IN SPHAEROPTERIS the sporangium of Anarthropteris lanceolata (Hook. f.) Pic. Serm. (as A. dictyopteris (Mett.) Copel.) (Wilson, 1960). As pointed out in a study of mature sporangia of species of the Polypodiaceae, Grammitidaceae, and Vittariaceae (Wilson, 1959), the cell arrangement in the sporangia reflect the ontogeny of these structures and, with but few exceptions, there is no reason to doubt that the development of the capsules follows the pattern of those of Phlebodium (Wilson, 1958a), Xiphopteris and Pyrrosia (Wilson, 1958b), and Anarthropteris (Wilson, 1960). Edwards (1996) expanded the examination of the structure of mature sporangia by initiating a survey of the cellular structure of the capsules of more than 110 species in 20 families. Three of these species were illustrated in his published abstract. Sporangia with four-rowed stalks, however, are known in several fern genera including Dipteris, Cheiropleuria, and members of the Cyatheaceae. Wilson (1959) pointed out that it was not possible to homologize the sporangial faces of Dipteris and Cheiropleuria with those of the higher leptosporangiate ferns. The known developmental patterns cannot give rise to a four-rowed stalk. Bower (1915) wrote that in Cheiropleuria sporangia with four-rowed stalks, the segmentation of the young sporangium, "Appears to show a regular cleavage of the segments in two opposite rows," and the "Subdivision of the two rows of segments of the stalk by walls in the plane of the drawings has given rise to the four rows of cells of the stalk, as seen in later stages." This suggests a distinctly different developmental pattern in these sporangia than is known. The only studies of the development of sporangia with four-rowed stalks are those of Bower (1915, 1923, 1926). Holttum and Sen (1961), in their paper "Morphology and classification of the tree ferns" did not make a detailed examination of the sporangia, but based their comments mostly on Bower's publications. For a clear understanding of the structure of the sporangia with fourrowed stalks their ontogeny needs to be studied in detail. Because it is readily available in cultivation in southern California, Sphaeropteris cooperi (F. Muell.) R.M. Tryon [Cyathea cooperi (F. Muell.) Domin] was chosen for study to serve as a model for the pattern of development of sporangia with four-rowed stalks. MATERIALS AND METHODS The material used in this study was collected from plants in cultivation in Los Angeles, California. A specimen of this fern has been deposited in the herbarium of Rancho Santa Ana Botanic Garden (Wilson 2067, RSA). Slides are deposited at Rancho Santa Ana Botanic Garden. Fertile pinnae of Sphaeropteris cooperi in early and increasingly mature stages of development were preserved in formalin-aceto alcohol (FAA). Sori were processed by three different methods: 1) Fertile pinnules were infiltrated with the tertiary butyl alcohol series, embedded in paraffin, and sectioned at 10,Lm. The sections were then stained in the Sharman (1943) series. 2) Fertile pinnules were cleared in 5% NaOH, bleached in 50% chlorine bleach, and stained in 3% tannic acid in 50% alcohol and 3% ferric chloride in 50% 205 This content downloaded from 207.46.13.149 on Wed, 28 Sep 2016 06:18:20 UTC All use subject to http://about.jstor.org/terms AMERICAN FERN JOURNAL: VOLUME 89 NUMBER 3 (1999) alcohol (the alcoholic stains were used to prevent maceration). After dehydration in alcohol, the sori were dissected from the pinnule lamina and placed on a slide in Diaphane. The sori were then teased to separate the sporangia and a coverslip was mounted. This technique resulted in an enormous amount of damage, but methodical searches of the slides and a large number of dissections revealed undamaged sporangia. This procedure of clearing and staining the sporangia allows both sides of each developing sporangium to be studied. 3) Young cleared fertile pinnules stained in tannic acid and ferric chloride were imbedded in paraffin, sectioned at 20pm, and mounted on slides. These preparations were studied to confirm the early division patterns observed in the other preparations. Mature sporangia were studied mounted in Crystal/Mount (Biomedia Corp., Foster City, California) on temporary slides. This process reduced the dehiscence of the capsules and at the same time prevented movement of the sporangia while being examined. All illustrations were made with the aid of a Leitz drawing tube on a Leitz microscope. Both sides of each cleared sporangium were drawn and each sporangial "Segment" is shaded to facilitate comprehension of the cell lineages in the developing sporangium. The shading patterns used conform with those used in earlier sporangial ontogenetic studies in order to allow for easier comparisons.

… to their inclusion in the single genus Alsophila. Species of Alsophila (in the present sense), … This redefinition of Alsophila obviates the need for a reclassification of the family. Such a …

… five species of Alsophila (Cyatheaceae) … Alsophila spores while differences were found at a specific level regarding sculpture. The spore wall organization and stratification of Alsophila …

… The genus Alsophila R. Brown comprises about 350 spe cies, widely distributed in the … The group of Alsophila swartziana falls under Alsophila in either classification. I agree with Holttum…

The percent spore germination, prothallial gross morphology, and the structure of sex organs on gametophytes of Alsophila hybrids were compared with those of Alsophila species. The …

Introduction The “rhizosphere effect” in plants occurs within approximately 5 mm from the root surface, where microbial communities exhibit distinct species composition and structural characteristics compared to non-rhizospheric soil. Root-associated fungi play crucial roles in nutrient acquisition enhancement, stress resistance improvement, organic matter decomposition, and carbon cycle promotion. Current research shows limited understanding of the rhizospheric fungal communities in Alsophila spinulosa, a rare and endangered plant species. Methods This study conducted a comparative analysis of fungal community composition and structural differences between A. spinulosa rhizospheric and non-rhizospheric soils. The functional roles of fungi in these distinct communities were systematically analyzed, with particular emphasis on identifying keystone fungal taxa within the rhizosphere, and explained the construction process of fungal communities. Results The results showed that there was no difference in α diversity between the rhizosphere and non-rhizosphere soil fungal communities of A. spinulosa, but the β diversity was significantly differentiated, indicating that the difference between rhizosphere and non-rhizosphere fungal communities was mainly reflected in species composition rather than species number. The two communities have common dominant phylum: Ascomycetes and Basidiomycetes, and common dominant genera: Mortierella and Saitozyma. The functional type was mainly saprotic. Linear discriminant analysis effect size (LEfSe) analysis revealed four biomarker genera (Arthopyrenia, Hypochnicium, Tremella, and Syncephalis) enriched in the A. spinulosa rhizospheric fungal community. Venn diagram analysis identified 169 core genera within this community, with Flavodon exclusively present in the rhizosphere. Mechanistic analysis of community assembly demonstrated that stochastic processes predominantly governed the structuring of rhizospheric fungal communities. Discussion In conclusion, this study elucidates the functional composition and assembly mechanisms of rhizospheric fungal communities in A. spinulosa, while identifying keystone fungal taxa potentially critical to its survival. Future investigations should: Quantify the specific contribution of Flavodon to A. spinulosa; Decipher the mechanistic linkages between these fungi and the plant’s stress resistance traits; Implement plant–soil-microbe synergistic restoration strategies to enhance natural regeneration capacity of A. spinulosa populations.

BACKGROUND: Ferns have generally been neglected in studies of chloroplast genomics. Before this study, only one polypod and two basal ferns had their complete chloroplast (cp) genome reported. Tree ferns represent an ancient fern lineage that first occurred in the Late Triassic. In recent phylogenetic analyses, tree ferns were shown to be the sister group of polypods, the most diverse group of living ferns. Availability of cp genome sequence from a tree fern will facilitate interpretation of the evolutionary changes of fern cp genomes. Here we have sequenced the complete cp genome of a scaly tree fern Alsophila spinulosa (Cyatheaceae). RESULTS: The Alsophila cp genome is 156,661 base pairs (bp) in size, and has a typical quadripartite structure with the large (LSC, 86,308 bp) and small single copy (SSC, 21,623 bp) regions separated by two copies of an inverted repeat (IRs, 24,365 bp each). This genome contains 117 different genes encoding 85 proteins, 4 rRNAs and 28 tRNAs. Pseudogenes of ycf66 and trnT-UGU are also detected in this genome. A unique trnR-UCG gene (derived from trnR-CCG) is found between rbcL and accD. The Alsophila cp genome shares some unusual characteristics with the previously sequenced cp genome of the polypod fern Adiantum capillus-veneris, including the absence of 5 tRNA genes that exist in most other cp genomes. The genome shows a high degree of synteny with that of Adiantum, but differs considerably from two basal ferns (Angiopteris evecta and Psilotum nudum). At one endpoint of an ancient inversion we detected a highly repeated 565-bp-region that is absent from the Adiantum cp genome. An additional minor inversion of the trnD-GUC, which is possibly shared by all ferns, was identified by comparison between the fern and other land plant cp genomes. CONCLUSION: By comparing four fern cp genome sequences it was confirmed that two major rearrangements distinguish higher leptosporangiate ferns from basal fern lineages. The Alsophila cp genome is very similar to that of the polypod fern Adiantum in terms of gene content, gene order and GC content. However, there exist some striking differences between them: the trnR-UCG gene represents a putative molecular apomorphy of tree ferns; and the repeats observed at one inversion endpoint may be a vestige of some unknown rearrangement(s). This work provided fresh insights into the fern cp genome evolution as well as useful data for future phylogenetic studies.

To effectively preserve the vulnerable species of Alsophila, we studied the effects of varying the temperature and duration of storage on spore viability, early gametophyte development and the microstructure of brown spores of three Alsophila species. Spores of A. spinulosa (Wall. ex Hook.) Tryon and A. gigantea Wall. ex Hook. lost viability quickly when stored at room temperature and suffered from great loss when stored at –18°C from 6 to 12 months. Within 1 month, spore viability of A. spinulosa and A. gigantea stored at 4°C was higher than that of those stored in liquid nitrogen. In contrast, long-term storage in liquid nitrogen resulted in a comparatively small loss of viability for these two species. The spores of A. podophylla Hook. died within 3 months after storage at room temperature, 4°C and –18°C, and they died within 12 months when stored in liquid nitrogen. The spores of A. spinulosa and A. gigantea stored at room temperature, 4°C and –18°C, were prone to develop into abnormal gametophytes. These results suggest that storage of A. spinulosa and A. gigantea spores in liquid nitrogen is an effective method of preserving these vulnerable species. The reasons for the failure to preserve ephemeral A. podophylla spores by storage in liquid nitrogen are discussed.

… Three new interspecific hybrids of Alsophila have been detected in Cuba: A. ×boytelii in the Sierra Maestra range, E Cuba; A. ×medinae in the Trinidad Mountains, Central Cuba; and A. …

The rhizosphere is considered a highly complex and dynamic ecosystem. Rhizosphere soil microorganisms influence the growth and development of plants by mediating the transformation and absorption of nutrients. In order to explore the microbial community composition and diversity of Alsophila spinulosa growing in different habitats. Rhizosphere samples were collected from four different habitats within the Chishui Alsophila National Nature Reserve in Guizhou Province, China. According to the high-throughput sequencing results of 16 s rDNA and ITS, Proteobacteria and Ascomycota were the most abundant bacterial and fungal phyla in the rhizosphere soil of all four habitats. The alpha diversity analysis indicated that two particular habitats, Buddha Rock and Botanical Garden, harbored the highest microbial richness and diversity. LEfSe analysis revealed that Buddha Rock contained the highest relative abundance of Bacteroidetes compared to the other three study areas. Meanwhile, Tiantang Gou contained the highest relative abundance of Basidiomycota. Bacterial community composition and diversity were greatly influenced by soil pH, while fungal community composition and diversity were greatly influenced by available phosphorus, organic carbon, sucrase, and urease. The results of this study provide a scientific basis for the habitat restoration of A. spinulosa, and the improvement of the structure of the A. spinulosa rhizosphere soil microbial community. Laying a theoretical foundation for the next screening of inter-root functional flora.

… occur in the American tropics with Alsophila and … to Alsophila by the dark seta at the apex of the petiole scales, and Nephelea is a specialized development from a group in Alsophila. …

The taxonomic treatment of the Cyatheaceae has undergone numerous revisions as summarized in previous studies (Tryon, 1970; Gastony, 1973; Lucansky, 1974). Earlier research has shown the taxonomic importance of anatomy and morphology to the study of this group of ferns (Holttum & Sen, 1961; Sen, 1964; Lucansky, 1974; Lucansky & White, 1974). Yet, despite this renewal of interest in the tree ferns, comparative anatomical data are almost totally lacking for the neotropical species. Tryon's (1970) revised classification of the Cyatheaceae recognizes three basic evolutionary lines among the squamate genera, based upon petiole scale characters. The genera Alsophila and Nephelea, with structurally marginate petiole scales having dark apical setae, constitute one evolutionary line. Similarities in the sporogenetic pattern, spore morphology, basal pinna structure, and potential for squaminate spine development also demonstrate a close phyletic relationship between these two genera (Gastony, 1973, p. 83). An attempt is made to determine whether the proposed phyletic relationship betweenA Isophila and Nephelea is supported by anatomical data. Our knowledge of anatomical data for the New World tree ferns is also increased. The following species were used in this study: Alsophila salvinii Hook., A. engelii Tryon, Nephelea erinacea (Karst.) Tryon var. erinacea, and N. polystichoides (Christ) Tryon. Voucher specimens are on file in the herbarium of Duke University. Developing shoot tips were collected in the moist, tropical, mountainous regions of Costa Rica and Venezuela. The plant materials were killed and fixed in formalin-acetic acid-alcohol (FAA) and sectioned on a "macrotome" (Lucansky, 1976b). The sections (slices) were partitioned into manageable sizes, dehydrated in a tertiary-butyl alcohol series, and embedded in paraffin (Johansen, 1940). Sections (8 um) were made and stained with safranin-fast green. Parts of stained sections were photographed with a 35 mm Zeiss C35 camera, whereas entire sections (slices) were photographed with a 35 mm single-lens reflex camera.

Alsophila spinulosa (Wall. ex Hook) Tryon is one of the few remaining tree ferns on Earth. As a living Mesozoic fern fossil, it has great significance for studies on paleo-climate and paleo-…

… Alsophila 9 spp., Alsophila sect. Gymnosphaera 1 sp., Cyathea 72 spp.), with 13 endemic … one in Alsophila. The following new species are described and illustrated: Alsophila gastonyi, …

Breeding‐system data have been available for a large number and diverse array of angio‐sperms for a relatively long time. In contrast, breeding systems of ferns and their allies (…

Morphological and chemosystematic studies demonstrate that three endemic Puerto Rican tree ferns, Alsophila bryophila, A. dryopteroides and Nephelea portoricensis have been …

Rhoptroceros cyatheae (Hymenoptera: Selandriidae) is a dominant herbivorous pest of Alsophila spinulosa in southwestern China, including Guizhou and Sichuan provinces. Infestation by this pest impairs spore reproduction of A. spinulosa and reduces the photosynthetic capacity of host plants. However, the chemosensory genes of R. cyatheae have not been reported, and the molecular basis of antennal detection of host volatile organic compounds (VOCs) is poorly understood. This study aims to screen and identify bioactive VOCs potentially involved in host searching behavior of R. cyatheae, analyze antennal VOC detection patterns, and explore the in vitro binding characteristics of an odorant-binding protein (OBP) involved in olfactory recognition, thereby providing a preliminary theoretical basis for the green management of R. cyatheae. Dynamic headspace sampling, gas chromatography-mass spectrometry (GC-MS), and gas chromatography-electroantennography (GC-EAD) were used to measure antennal electrophysiological responses of R. cyatheae to volatiles from its host A. spinulosa. Y-tube olfactometer assays were conducted to evaluate behavioral responses. For RcyaOBP7, fluorescence competitive binding assays, structural modeling, and molecular docking were integrated to investigate its in vitro binding characteristics with nine selected bioactive VOCs. Nine A. spinulosa volatiles were identified that elicited antennal electrophysiological responses in R. cyatheae, and the sawfly showed behavioral orientation to these VOCs, confirming that its antennae can detect host VOCs. In vitro binding assays showed that RcyaOBP7 exhibited strong binding affinity to p-ethylacetophenone, suggesting its potential involvement in antennal olfactory recognition of this volatile. Specific VOCs released by A. spinulosa are among the signaling molecules detected by the antennae of R. cyatheae. In vitro findings indicate that RcyaOBP7 binds specifically to p-ethylacetophenone, suggesting a possible role in antennal olfactory recognition and behaviors such as host location. However, in vivo functional validation and field trials under ecologically relevant conditions are needed to confirm these roles. This study characterizes the in vitro binding properties of RcyaOBP7 and provides a basis for further research on green management strategies for R. cyatheae based on antennal olfactory signals.

Island endemics are significant due to their unique genetic composition and their vulnerability to a high risk of extinction. The tropical island, Sri Lanka, harbors approximately 389 …