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Dennstaedtiaceae is a monophyletic fern family widespread in tropical and temperate regions. Data on the anatomy of its species in Peninsular Malaysia are still scarce. Here, we examined anatomical characteristics (leaf venations & shape of steles) among ten species of seven Dennstaedtiaceae genera recorded in Peninsular Malaysia. Two types of vein patterns were observed, most of them having open-leaf venation whereas closed venation was observed only in Histiopteris species. Four types of steles which were 'U'-shaped, 'I'-shaped, scattered, and a combination of 'S' and 'W-shaped and a combination of inverted 'C' and 'W'-shaped' were observed among all the Dennstaedtiaceae species studied. [ABSTRACT FROM AUTHOR]

Introduction: Natural hybridization is common and plays a crucial role in driving biodiversity in nature. Despite its significance, the understanding of hybridization in ferns remains inadequate. Therefore, it is imperative to study fern hybridization to gain a more comprehensive understanding of fern biodiversity. Our study delves into the role of hybridization in shaping fern species, employing Microlepia matthewii as a case study to investigate its origins of hybridization. Methods: We performed double digest Genotyping-by-sequencing (dd-GBS) on M. matthewii and its potential parent species, identifying nuclear and chloroplast SNPs. Initially, nuclear SNPs were employed to construct the three cluster analysis: phylogenetic tree, principal component analysis, and population structure analysis. Subsequently, to confirm whether the observed genetic mixture pattern resulted from hybridization, we utilized two methods: ABBABABA statistical values in the D-suite program and gene frequency covariance in the Treemix software to detect gene flow. Finally, we employed chloroplast SNPs to construct a phylogenetic tree, tracing the maternal origin. Results and discussion: The analysis of the nuclear SNP cluster revealed that M. matthewii possesses a genetic composition that is a combination of M. hancei and M. calvescens. Furthermore, the analysis provided strong evidence of significant gene flow signatures from the parental species to the hybrid, as indicated by the two gene flow analyses. The samples of M. matthewii cluster separately with M. hancei or M. calvescens on the chloroplast systematic tree. However, the parentage ratio significantly differs from 1:1, suggesting that M. matthewii is a bidirectional and asymmetrical hybrid offspring of M. hancei and M. calvescens. [ABSTRACT FROM AUTHOR]

Premise: Bracken (Pteridium, Dennstaedtiaceae) is a cosmopolitan genus of aggressive disturbance colonizers that are toxic to agricultural livestock. The taxonomy of Pteridium has been treated in multiple schemes, ranging from one to six species worldwide, with numerous subspecies and varieties. Recent work has focused on the worldwide distribution and systematics of the bracken fern, but South America has been poorly represented. We present the first continent‐wide sampling and analysis of Pteridium esculentum, a Southern Hemisphere diploid species. Methods: Within South America, P. esculentum has several morphotypes, distinguished into subspecies by variation in indument and lamina architecture. We used double digest restriction site‐associated DNA sequencing (ddRADSeq) to assess the phylogenetic relationships of P. esculentum subspecies. Results: We found a striking genetic homogeneity in the species, being able to support only two morphotypes from molecular data: P. e. arachnoideum and P. e. campestre. We had high confidence for shallow and deep phylogenetic relationships, but less support for relationships among crown groups. Conclusions: We describe an east‐west geographic pattern that would explain the relationships between populations; and, in contrast to previous studies, we detected differences with P. esculentum from Australia. These results will lay the foundations for studying variations in this species' behavior as a weed, as well as its impact on the production of agricultural livestock in South America. [ABSTRACT FROM AUTHOR]

Abstract Background Polypodiales suborder Dennstaedtiineae contain a single family Dennstaedtiaceae, eleven genera, and about 270 species, and include some groups that were previously placed in Dennstaedtiaceae, Hypolepidaceae, Monachosoraceae, and Pteridaceae. The classification and phylogenetic relationships among these eleven genera have been poorly understood. To explore the deep relationships within suborder Dennstaedtiineae and estimate the early diversification of this morphologically heterogeneous group, we analyzed complete plastomes of 57 samples representing all eleven genera of suborder Dennstaedtiineae using maximum likelihood and Bayesian inference. Results The phylogenetic relationships of all the lineages in the bracken fern family Dennstaedtiaceae were well resolved with strong support values. All six genera of Hypolepidoideae were recovered as forming a monophyletic group with full support, and Pteridium was fully supported as sister to all the other genera in Hypolepidoideae. Dennstaedtioideae (Dennstaedtia s.l.) fell into four clades with full support: the Microlepia clade, the northern Dennstaedtia clade, the Dennstaedtia globulifera clade, and the Dennstaedtia s.s. clade. Monachosorum was strongly resolved as sister to all the remaining genera of suborder Dennstaedtiineae. Based on the well resolved relationships among genera, the divergence between Monachosorum and other groups of suborder Dennstaedtiineae was estimated to have occurred in the Early Cretaceous, and all extant genera (and clades) in Dennstaedtiineae, were inferred to have diversified since the Late Oligocene. Conclusion This study supports reinstating a previously published family Monachosoraceae as a segregate from Dennstaedtiaceae, based on unique morphological evidence, the shady habitat, and the deep evolutionary divergence from its closest relatives.

Premise of research. From a purely palynological perspective, lowest Danian fern-dominated assemblages of the Williston Basin (North Dakota and southwestern Saskatchewan) and the Raton Basin (northeastern New Mexico and southeastern Colorado) appear indistinguishable, although this perspective has yet to be corroborated by macrofloral studies across this same region. No ferns have been collected from the lowest Danian barren series of the Raton Formation in more than a century, and this section remains sparsely sampled. Methodology. New collections of fossil ferns from the basal portion of the barren series or informal middle member of the Raton Formation, which directly overlies the K/Pg boundary, are compared with contemporaneous assemblages in other North American depositional basins. Pivotal results. Dennastra sorimarginata McIver and Basinger (Dennstaedtiaceae Lotsy) and Woodwardia arctica (Heer) Brown (Blechnaceae Newman) that produce Cyathidites diaphana (Wilson and Webster) Nichols and JL Brown and Laevigatosporites haardtii (Potonié and Venitz) Thomson and Pflug, respectively, are recognized as characteristic ferns in the basal portion of the barren series, in addition to Osmunda macrophylla Penhallow. Conclusions. In accordance with palynological perspectives, lowest Danian fern macrofossil assemblages from the Raton Basin support the concept of a geographically widespread "postdisaster" pteridophyte flora represented predominantly by Dennstaedtiaceae and Blechnaceae, with other minor components of more northern assemblages. The enigmatic hypothesis of a landscape dominated by anemiaceous or schizaeaceous ferns is rejected on the basis of this new evidence, which suggests that Cyathidites diaphana –producing dennstaedtiaceous ferns were the K/Pg boundary "disaster taxon" and among those that flourished in the Raton Basin. [ABSTRACT FROM AUTHOR]

Background: Polypodiales suborder Dennstaedtiineae contain a single family Dennstaedtiaceae, eleven genera, and about 270 species, and include some groups that were previously placed in Dennstaedtiaceae, Hypolepidaceae, Monachosoraceae, and Pteridaceae. The classification and phylogenetic relationships among these eleven genera have been poorly understood. To explore the deep relationships within suborder Dennstaedtiineae and estimate the early diversification of this morphologically heterogeneous group, we analyzed complete plastomes of 57 samples representing all eleven genera of suborder Dennstaedtiineae using maximum likelihood and Bayesian inference. Results: The phylogenetic relationships of all the lineages in the bracken fern family Dennstaedtiaceae were well resolved with strong support values. All six genera of Hypolepidoideae were recovered as forming a monophyletic group with full support, and Pteridium was fully supported as sister to all the other genera in Hypolepidoideae. Dennstaedtioideae (Dennstaedtia s.l.) fell into four clades with full support: the Microlepia clade, the northern Dennstaedtia clade, the Dennstaedtia globulifera clade, and the Dennstaedtia s.s. clade. Monachosorum was strongly resolved as sister to all the remaining genera of suborder Dennstaedtiineae. Based on the well resolved relationships among genera, the divergence between Monachosorum and other groups of suborder Dennstaedtiineae was estimated to have occurred in the Early Cretaceous, and all extant genera (and clades) in Dennstaedtiineae, were inferred to have diversified since the Late Oligocene. Conclusion: This study supports reinstating a previously published family Monachosoraceae as a segregate from Dennstaedtiaceae, based on unique morphological evidence, the shady habitat, and the deep evolutionary divergence from its closest relatives. [ABSTRACT FROM AUTHOR]

Introduction: Natural hybridization is common and plays a crucial role in driving biodiversity in nature. Despite its significance, the understanding of hybridization in ferns remains inadequate. Therefore, it is imperative to study fern hybridization to gain a more comprehensive understanding of fern biodiversity. Our study delves into the role of hybridization in shaping fern species, employing Microlepia matthewii as a case study to investigate its origins of hybridization., Methods: We performed double digest Genotyping-by-sequencing (dd-GBS) on M. matthewii and its potential parent species, identifying nuclear and chloroplast SNPs. Initially, nuclear SNPs were employed to construct the three cluster analysis: phylogenetic tree, principal component analysis, and population structure analysis. Subsequently, to confirm whether the observed genetic mixture pattern resulted from hybridization, we utilized two methods: ABBA-BABA statistical values in the D-suite program and gene frequency covariance in the Treemix software to detect gene flow. Finally, we employed chloroplast SNPs to construct a phylogenetic tree, tracing the maternal origin., Results and Discussion: The analysis of the nuclear SNP cluster revealed that M. matthewii possesses a genetic composition that is a combination of M. hancei and M. calvescens . Furthermore, the analysis provided strong evidence of significant gene flow signatures from the parental species to the hybrid, as indicated by the two gene flow analyses. The samples of M. matthewii cluster separately with M. hancei or M. calvescens on the chloroplast systematic tree. However, the parentage ratio significantly differs from 1:1, suggesting that M. matthewii is a bidirectional and asymmetrical hybrid offspring of M. hancei and M. calvescens ., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Luo, Shang, Xue, Wang, Dai, Shen and Yan.)

Premise of research. Newly recognized compression fossils of fertile leptosporangiate ferns assignable to Dennstaedtia Bernh. (Dennstaedtiaceae) and Hymenophyllum Sm. (Hymenophyllaceae) are described from the latest early Eocene floras of the Okanogan Highlands, British Columbia, Canada, and northeastern Washington. Methodology. Specimens were photographed with reflected light microscopy and were studied morphologically in comparison with related fossil and extant forms. Focus-shift stacking was used to layer photos of some specimens. Some were photographed with polarized light. The holotype specimen of Dennstaedtia christophelii sp. nov. was also studied with environmental scanning electron microscopy. Pivotal results. We describe D. christophelii sp. nov. (Dennstaedtiaceae) and Hymenophyllum axsmithii sp. nov. (Hymenophyllaceae) on the basis of vegetative and fertile remains of fragmentary fronds. Specimens of D. christophelii are one-pinnate-pinnatifid to bipinnate and bear frequent marginal round sori in cuplike indusia on small crenulate to dissected pinnae. Sporangia each have a prominent annulus with approximately six to eight long cells visible. Hymenophyllum axsmithii has the type of lamina cutting, sorus position, alate rachis, sorus shape, and venation corresponding to Hymenophyllum , subgenus Sphaerocionium (Hymenophyllaceae). The numerous sporangia per sori each bear a prominent annulus, and 7–10 casts of spores are noted in some sporangia. Conclusions. These fossils document the occurrence of leptosporangiate fern diversity in the early Eocene Okanogan Highlands floras. Dennstaedtia christophelii represents one of several occurrences of Dennstaedtiaceae in the Eocene. Hymenophyllum axsmithii is the first unequivocal member of Hymenophyllaceae to be reported from these diverse plant and insect assemblages from lacustrine and swamp settings under warm temperate climates of the latest early Eocene. [ABSTRACT FROM AUTHOR]

With the development of open science and technological innovation, using sharing data and molecular biology techniques in the study of taxonomy and systematics have become a crucial component of plants, which undoubtedly helps us discover more hidden outliers or deal with difficult taxa. In this paper, we take Dennstaedtia smithii as an example, based on sharing molecular database, virtual herbarium and plant photo bank, to clarify the outliers that have been hidden in Dennstaedtia and find the key morphological traits with consistent of molecular systematics. In molecular phylogenetic analyses, we used rbcL, rps4, psbA-trnH and trnL-F sequences from 5 new and 49 shared data; the results showed that Dennstaedtia smithii is nested within Microlepia rather than Dennstaedtia. We further studied the morphological characters based on the phylogeny result and found that D. smithii is distinguished from other species of Dennstaedtia by spore ornamentation and the unconnected of grooves between rachis and pinna rachis. According to morphological and molecular phylogenetic studies, our results supported that D. smithii should be a new member of Microlepia and renamed Microlepia smithii (Hook.) Y.H. Yan. Finding hidden outliers can promote the consistency of morphological and molecular phylogenetic results, and make the systematic classification more natural. [ABSTRACT FROM AUTHOR]

Blotiella currorii (Hook.) R.M.Tryon. (Dennstaedtiaceae), Dicranopteris linearis (Burm.F.) Underw. (Gleicheniaceae), and Aleuritopteris farinosa (Forssk.) Fée (Pteridaceae) are reported for the first time in the flora of Senegal. They represent not only three more species but also two new families, Dennstaedtiaceae and Gleicheniaceae, for Senegal. Data on species, morphology, taxonomy, ecology, and geographic distribution are included. These three species were found in the interstices of the cliff of the 100-m Dindefelo Falls, which is in Kedougou region. [ABSTRACT FROM AUTHOR]

Compared to the leaf-miners and stem-miners on flowering plants, the miners on ferns (including both Lycopodiophyta and Polypodiophyta in the broad sense) are less known. Knowledge of miners and their host plants is essential to fully understand plant-insect interactions. Although there are many scattered records on fern miners, a worldwide checklist has not been reported. We provide a preliminary checklist of fern-mining insects and their host plants worldwide. Altogether, we found records for 128 species and 18 families of fern miners, mainly that feed on Dennstaedtiaceae, Equisetaceae, Polypodiaceae and Aspleniaceae. Fern miners belonged to four orders: Diptera (51 species; 39.8%), Coleoptera (33 species; 25.8%), Lepidoptera (28 species; 21.9%) and Hymenoptera (16 species; 12.5%). They are primarily known from the Palaearctic Region, Nearctic Region, Neotropical Region and Oriental Region. [ABSTRACT FROM AUTHOR]

The complete chloroplast DNA sequence of Hypolepis sparsisora was the first time to report with 150,839 bp in length. The structure of the chloroplast genome is composed in four regions, which consisted a large single-repeat region (LSC) of 84,285 bp, a small single-repeat region (SSC) of 21,390 bp, and two inverted repeat regions (IRs) of 22,582 bp, respectively. A total of 131genes including 8 rRNA genes, 35 tRNA genes, and 83 protein-coding genes were predicted. We obtained phylogenetic tree by using the complete chloroplast DNA of 15 species ferns. The ML and BI phylogenetic analysis showed the location of H. sparsisora in Dennstaedtiaceae and other families.

Ferns are known to contain long chain polyunsaturated fatty acids which may provide health benefits. The objective of this study was to investigate ferns of Pacific temperate regions (Far East of Russia and New Zealand) as sources of valuable fatty acids: arachidonic (20:4n-6) and eicosapentaenoic (20:5n-3). Fatty acids were analyzed in fronds of 23 fern species from 12 families. Major fatty acids include: 18:3n-3 (6–68% of total fatty acids), 16:0 (6–33%), 18:2n-6 (5–46%), 18:1n-9 (1–60%), 20:4n-6 (1–16%). Polyunsaturated fatty acids of fern fronds belong to the omega-6 (16:2n-6, 18:2n-6, 18:3n-6, 20:2n-6, 20:3n-6, 20:4n-6) and omega-3 (16:3n-3, 18:3n-3, 18:4n-3, 20:3n-3, 20:4n-3, 20:5n-3) families. For the first time, Δ5-unsaturated polymethylene-interrupted fatty acids were reported for ferns: sciadonic (5,11,14-20:3) and juniperonic (5,11,14,17-20:4) acids (up to 1.9% and 0.4%, respectively). Fatty acid profiles in fern fronds were unrelated to fern taxonomy, but affected by spore presence: fronds with sporangia/spores contained more 18:1n-9 and/or 18:2n-6. The absolute content of 20:4n-6 was found to be relatively constant for a species in different seasons. 20:5n-3 was a minor fatty acid (traces–5%) which accumulates during the vegetation period. Young fronds of the New Zealand ferns Phymatosorus pustulatus and Pteridium esculentum were enriched in 20:4n-6, while aged fronds of Cyathea dealbata had the highest level of 20:5n-3. The mature fronds of the Far Eastern ferns Phegopteris connectilis , Dryopteris expansa , and Athyrium sinense were also enriched in 20:5n-3. Image 1 • Fatty acid profiles of 23 fern species from New Zealand and Russia are presented. • This is the first report of Δ5-unsaturated polymethylene-interrupted acids in ferns. • The presence of spores significantly affects fatty acid profiles of fern fronds. • Fern species are investigated as sources of arachidonic and eicosapentaenoic acids. [ABSTRACT FROM AUTHOR]

Three tropical fern species previously treated in the Dennstaedtiaceae genus Hypolepis were recently segregated in a new genus, Hiya, based on phylogenetic analysis of chloroplast DNA sequences and assessment of their morphology. That study specifically mentioned the uncertain placement of the Australasian species Hypolepis distans, which has long been regarded as anomalous within Hypolepis. Using phylogenetic analysis of rbcL and rpl16 sequences, along with morphological and cytological characters, we show that Hypolepis distans is best placed in Hiya, and make the new combination Hiya distans. However, this requires a significant adjustment in the morphological characterisation of Hiya. It can be recognised by the adaxial sulcus of the primary pinnae being confluent with the rachis, veins which reach the lamina margin at an indentation, and the primary pinnae arising at ± 90° from the rachis. It is also a significant ecological extension of Hiya, from the tropical highlands of Malesia and Central and South American to the lowlands of temperate Australasia. [ABSTRACT FROM AUTHOR]

In the present communication, based on morphological characters, a new species of fern genus Microlepia C. Presl (Dennstaedtiaceae) is described from India. The described species is closely allied to Microlepia hispida C.Chr. from Vietnam, but differs in size and shape of lamina, stipe lamina ratio (stipe is shorter than lamina), basal pinnae and shape of pinnules, degree of hairiness, colour and thickness of hairs, and presence of dense thick hairs on upper surface. [ABSTRACT FROM AUTHOR]

Seven new species and one new variety of Hypolepis are presented, bringing the total recognized for the genus in the Neotropics to about 50 species (and a total of 60 taxa). The new taxa include H. barringtonii (endemic to Florida, U.S.A.), H. cubensis (endemic to Cuba), H. feeana (from Colombia, Venezuela, and the Antilles), H. zimmerae (from Costa Rica, Colombia, Ecuador, and Peru), H. sunduei (endemic to Peru), H. forzzae (endemic to Amazonas, in the border of Brazil and Venezuela), H. miodelii (endemic to Rio de Janeiro, Brazil), and H. rigescens var. paranaensis (endemic to Paraná, Brazil). All new taxa are described, illustrated, and discussed. Treatments of H. flexuosa and H. stuebelii are provided because the description of H. zimmerae and H. feeana alters their circumscription, respectively. It is also suggested that H. repens does not occur in Florida, Cuba, nor Jamaica. [ABSTRACT FROM AUTHOR]

The relationship of Hypolepis brooksiae , H. nigrescens , and H. scabristipes to the remainder of Hypolepis (Dennstaedtiaceae) has been questioned by previous authors based on their unique combination of morphological characters and different base chromosome number. Using four chloroplast genes including rbcL , atpA , rpL6 , and rps4 - trnS intergenic spacer (IGS) from 32 samples, representing 24 species of Dennstaedtiaceae, we recovered a clade comprising H. brooksiae and H. nigrescens , distinct from the remaining species of Hypolepis . This clade is resolved as sister to the clade comprising Blotiella , Paesia and Histiopteris . We reconstructed ancestral states of 16 morphological characters and found that this clade is distinguished by indeterminate, scandent leaves exhibiting rhythmic growth, provided with recurved black-tipped prickles, and stipule-like pinnules that protect the emerging crosier and pinnae departures, rachis-costa architecture where the adaxial sulcus is confluent with the next lower order, and a base chromosome number of x = 29. In light of this molecular and morphological evidence, we describe a new genus, Hiya , and provide nomenclatural combinations to accommodate the three known species segregated from Hypolepis : Hiya brooksiae , Hiya nigrescens , and Hiya scabristipes . [ABSTRACT FROM AUTHOR]

Plantas herbáceas terrestres, epífitas o hemiepífitas; rizomas cortos a larga¬ mente postrados, rara vez erectos, con tricomas articulados y/o escamas; hojas monomorfas, erectas o escandentes, con venación circinada, peciolos general¬ mente con yemas en la base, sulcados del lado adaxial, láminas 1-4-pinnadas, membranosas o coriáceas, glabras o con tricomas septados, crispado-flexuosos o rígidos, anádromas, venas libres, con ápice engrosado terminando cerca del margen o reticuladas sin venillas libres incluidas, raquis (costa) primario y otros ejes sulcados en la cara adaxial, sulcos continuos con los del siguiente orden o interrumpidos; soros marginales o submarginales, circulares, oblongos o lineares, 1-plurinervados, indusios dobles, formados por el margen laminar recurvado del segmento y el tejido del envés o simples y constituidos sólo por el margen laminar recurvado; esporangios con pedicelos, parafisos septados, anillo vertical interrum¬ pido por el pedicelo o ligeramente oblicuo; esporas monoletes o triletes, sin perisporio o rara vez con él. [ABSTRACT FROM AUTHOR]

Based on field observations and examinations of herbarium specimens (including type material), consulting the original literature and molecular phylogenetic analysis of the rbcL and trnL-F sequences, it is concluded that Hypolepis robusta is conspecific with Hypolepis alpina and is here formally treated as a synonym of it. Additionally H. alpina is reported with new distribution records in Guangdong, Guangxi and the Hainan Island of China, respectively. [ABSTRACT FROM AUTHOR]

Descreve-se o perfil de 40 propriedades rurais com pastagens invadidas por Pteridium arachnoideum na região norte de Mato Grosso, bem como a prevalência de hematúria enzoótica bovina (HEB) em bovinos de leite e corte nessa região. A HEB foi observada em 15/40 propriedades com prevalências variando entre 0,8 e 16,6%. Aspectos relacionados à implantação das pastagens e manejos utilizados foram discutidos. A maior parte das propriedades que apresentaram HEB possuíam pastagens altamente invadidas pela planta, enquanto que a maioria das propriedades que nunca apresentaram animais acometidos por HEB possuíam pastos com áreas invadidas abaixo de 10%. O desmatamento e a utilização de queimada foram fatores determinantes na invasão de piquetes por P. arachnoidem.

As part of the Flora of Espírito Santo project, it is presented the taxonomic treatment of Dennstaedtiaceae, with keys, descriptions, illustrations, and list of specimens examined. In this state (and adjacent areas of Minas Gerais), eleven taxa of Dennstaedtiaceae were found: Blotiella lindeniana, Dennstaedtia cicutaria, Dennstaedtia cornuta, Dennstaedtia globulifera, Histiopteris incisa, Hypolepis acantha, Hypolepis mitis, Hypolepis rigescens var. rigescens, Hypolepis rugosula subsp. pradoana, Pteridium arachnoideum subsp. arachnoideum, and Pteridium arachnoideum subsp. campestre. Most of these taxa are widespread along the Neotropics, but three (or four) are endemic to the Brazilian Atlantic Rainforest: Hypolepis acantha, Hypolepis mitis, and Hypolepis rugosula subsp. pradoana (and possibly Dennstaedtia cornuta). [ABSTRACT FROM AUTHOR]

Forest recovery on disturbed areas is of special significance in the Ecuadorian Andes, where deforestation is a serious problem. Natural diachronic succession was evaluated on three large plots or sites, differing in their land use and vegetation composition, one is dominated by grass species on an abandoned pasture (Pasture site), the other two are post-fire vegetation dominated by bracken (Bracken site) and various shrubs (Shrub site). Additionally, we assessed the effectiveness of manual removal of competitive herbaceous species to accelerate forest recovery. Monitoring was done in 2003, 2005 and 2007 on 48 subplots of 116 m each recording species richness and woody-species density. Results showed that the Pasture site demonstrated a competitive effect of exotic grasses on woody species recruitment with much lower species recruitment and density, suggesting serious inhibition of natural forest regeneration and an unclear successional trajectory. The Bracken and Shrub sites became significantly similar floristically and there is evidence for a marked facilitation of woody plant recruitment correlated with light availability on the ground. Both sites showed characteristics of classic succession, with Shrub showing a higher species richness and density while late-successional species are poorly represented on the Bracken site. However, NMDS ordination using species density showed that the two trajectories may not be converging towards a common 'final state'. Manual weeding was ineffective for accelerating forest recovery. These results suggest that the main limiting factor for the recruitment of woody species on the Pasture site is strong grass competition and must be addressed before seed availability, while seed availability seems to be the constraining factor for Bracken and Shrub site development, thus direct seeding or planting may be effective in accelerating forest recovery. [ABSTRACT FROM AUTHOR]

The rise of angiosperms during the Cretaceous was thought to be related to the radiation of polypod ferns, a fern lineage that represent 80% of the modern fern diversity. However, although the proposed palo-diversity from DNA based studies, Mesozoic polypod fern fossils with preserved fertile pinnae are scarcely. Here, we investigated the fragment of polypod fern preserved in mid-Cretaceous Kachin amber from northern Myanmar and assigned a new fossilized fertile pinnule into the genus Microlepia (Dennstaedtiaceae), described as Microlepia burmasia Long, Wang and Shi, sp. nov. The new species is mainly characterized by the 2-pinnate-pinnatifid pinnule with surface and margin covering short tomentum and articulate hairs. Vein free, pouch-shaped indusia, submarginal and terminal on one vein of sori, sporangium with interrupted, vertical annulus and spores trilete. This discovery adds to polypod fern diversity in the Cretaceous and dates the origin of Microlepia to at least 60 million years earlier, which is evidence for an early origin of polypod ferns and coincides with the rise of angiosperms. [ABSTRACT FROM AUTHOR]

This paper presents complementary data to the recently published taxonomic treatment of the Hypolepis rugosula complex around the world, with special reference to Africa and surrounding islands. Here we present a new subspecies from South Africa ( H. rugosula subsp. rouxii) and another from Bioko, Equatorial Guinea ( H. rugosula subsp. formosa). We present an updated nomenclatural paragraph for H. rugosula subsp. africana, along with the lectotypification of one heterotypic synonym ( Phegopteris boryana) and comments regarding similar but unrelated names (e.g. Aspidium boryanum). We also transfer H. goetzei to the synonymy of H. rugosula subsp. pichi-sermolliana, choosing a new lectotype for it. The population of H. rugosula from South Africa (= subsp. rouxii) is likely to be the source population for populations of Saint Helena (= subsp. viscida) and Ascension Island (= subsp. brownseyana), based on morphological comparisons and on the anticlockwise wind direction. Based on the latitude, H. rugosula subsp. formosa would be expected to be found only at the higher elevations in Bioko (above 2,000 m a.s.l.), but it is also found at mid-elevations (ca 700 m a.s.l.). Apparently, this is a natural pattern of islands and is increased by deforestation. We also offer further taxonomic and ecological comments on the complex, additional examined specimens and maps of distribution in Africa with real occurrences and modelled distributions. The modelled distribution map (based on climatic data) confirms the disjunction of the African subspecies. [ABSTRACT FROM AUTHOR]

Dennstaedtiaceae is a medium-sized family of ferns in New Zealand with 11 indigenous and two naturalised species. Lindsaeaceae is a small family with just three native species and one naturalised. Three lectotypes are chosen for basionyms relevant to New Zealand:Dicksonia davallioidesR.Br.,Lindsaea trilobataColenso andPteris vespertilionisLabill. Justification for the choice is provided in each case. This short communication is a contribution towards clarifying the taxonomic and nomenclatural status of New Zealand plants for the plant names database (Ngā Tipu Aotearoa) and the electronic Flora of New Zealand. [ABSTRACT FROM AUTHOR]

Researchers at Tanis, North Dakota, U.S.A., cited faulting associated with soft sediment deformation of the K/Pg boundary clay at Madrid East in the Raton Basin, U.S.A., as additional evidence of "more-instantaneous effects" that preceded the longer-term, climatic effects of the Chicxulub impact. However, Madrid East is among numerous localities where the initial phase of the K/Pg boundary fern spike initiated within rather than above the K/Pg boundary clay crosscut by this fault. Accordingly, this phase of the K/Pg boundary fern spike must have preceded the cessation of seismic aftershocks of the Chicxulub impact—a conclusion also reached by researchers at the deep marine depositional setting of Gorgonilla Island in Colombia, South America. The observation that the Chicxulub impact winter was shorter in duration than post-impact seismicity need not signify a major dilemma for contemporary climate models of the Chicxulub impact, a dilemma originally exacerbated by the common perception that this phase of the fern spike was dominated by tropical tree ferns. Because tree ferns have exceptionally long generation times (ca. 100 y according to contemporary estimates), they could not have had ample time to reach sporing stage if they were killed back to rhizomes or other belowground reserves by a complete shutdown of photosynthesis and subsequent impact winter. Alternatively, the dennstaedtiaceous affinity of spores at Madrid East suggests that these ferns had a generation time of only 2–4 y, which better fits contemporary estimates on how long it took for the effects of Chicxulub to wind down. • Tanis researchers suggest seismic aftershocks preceded the K/Pg impact winter. • The first phase of the fern spike preceded the cessation of aftershocks. • The generation time of Dennstaedtiaceae, not Cyatheaceae, fits Chicxulub models. • Seismic aftershocks occur many years after major mainshocks. • The first plants recovered within a few years of the impact. [ABSTRACT FROM AUTHOR]

O presente trabalho trata da pteridoflora da Mata do Estado, localizada no município de São Vicente Férrer, Zona da Mata norte do estado de Pernambuco. Esta área, com extensão aproximada de 600 ha e localizada a 600-650 m de altitude, é ocupada originalmente por floresta úmida e fragmentos de floresta serrana (Floresta Ombrófila Densa Submontana), estando ainda bem conservada. Este artigo apresenta o tratamento taxonômico das famílias Cyatheaceae e Dennstaedtiaceae na área de estudo. São apresentadas chaves para a identificação dos gêneros e espécies, bem como ilustrações, descrições das espécies e comentários sobre todos os táxons. Cyatheaceae está representada na área estudada por Alsophila sternbergii (Sternb.) Conant, Cyathea abreviata Fernandes, C. microdonta (Desv.) Domin, C. phalerata Mart. e C. pungens (Willd.) Domin; Dennstaedtiaceae está representada por Hypolepis repens (L.) C. Presl, Lindsaea lancea (L.) Bedd. var. lancea, Pteridium arachnoideum (Kaulf.) Maxon e Saccoloma elegans Kaulf.

Phytochemical investigation of the dry fronds of Microlepia pilosissima resulted in the isolation of three new lupane triterpenes, 3β,11α,28-trihydroxy-29-nor-lupan-20-one ( 1), 3β,11α-dihydroxy-29-nor-lupan-20-on-28-al ( 2), and 3β-acetyl-29-nor-lupan-20-on-28-al ( 3), together with a known compound 3β,11α-dihydroxy-29-nor-lupan-20-one ( 4). The structures of these compounds were elucidated mainly on the basis of spectroscopic analyses, including 1D and 2D NMR and mass spectroscopic methods. [ABSTRACT FROM AUTHOR]

The neotropical bracken fern Pteridium arachnoideum (Kaulf.) Maxon. (Dennstaedtiaceae) is described as an aggressive pioneer plant species. It invades abandoned or newly burned areas and represents a management challenge at these invaded sites. Native to the Atlantic Forest and Cerrado (Tropical Savanna) Brazilian biomes, P. arachnoideum has nevertheless become very problematic in these conservation hotspots. Despite some reports suggesting a possible role of allelopathy in this plant’s dominance, until now there has been little evidence of isolated and individually identified compounds with phytotoxic activities present in its tissues or in the surrounding environment. Thus, the aim of this study was to investigate the allelopathic potential of P. arachnoideum by isolating and identifying any secondary metabolites with phytotoxic activity in its tissues, litter, and soil. Bioguided phytochemical investigation led to the isolation and identification of the proanthocyanidin selligueain A as the major secondary compound in the green fronds and litter of this fern. It is produced by P. arachnoideum in its green fronds, remains unaltered during the senescence process, and is the major secondary compound present in litter. Selligueain A showed phytotoxic activity against the selected target species sesame (Sesamum indicum) early development. In particular, the compound inhibited root and stem growth, and root metaxylem cell size but did not affect chlorophyll content. This compound can be considered as an allelochemical because it is present in the soil under P. arachnoideum patches as one of the major compounds in the soil solution. This is the first report of the presence of selligueain A in any member of the Dennstaedtiaceae family and the first time an isolated and identified allelochemical produced by members of the Pteridium species complex has been described. This evidence of selligueain A as a putative allelochemical of P. arachnoideum reinforces the role of allelopathy in the dominance processes of this plant in the areas where it occurs. [ABSTRACT FROM AUTHOR]

Systematic phytochemical investigations of the underground rhizome of Pteridium aquilinum (L.) Kuhn (Dennstaedtiaceae) afforded thirty-five pterosins and pterosides. By detailed analysis of one- and two-dimensional nuclear magnetic resonance spectroscopy, circular dichroism (CD) and high-resolution mass spectrometric data, thirteen previously undescribed pterosins and pterosides have been identified. Interestingly, for the first time 12- O - β -D-glucopyranoside substituted pterosins, rhedynosides C and D, and the sulfate-containing pterosin, rhedynosin H, alongside the two known compounds, histiopterosin A and (2 S )-pteroside A2, were isolated from the rhizomes of subsp. aquilinum of bracken. In addition, six-membered cyclic ether pterosins and pterosides, rhedynosin A and rhedynoside A, are the first examples of this type of pterosin-sesquiterpenoid. Additionally, the three previously reported compounds (rhedynosin I, (2 S )-2-hydroxymethylpterosin E and (2 S )-12-hydroxypterosin A) were obtained for the first time from plants as opposed to mammalian metabolic products. Single crystal X-ray diffraction analysis was applied to the previously undescribed compounds (2 R )-rhedynoside B, (2 R )-pteroside B and (2 S )-pteroside K, yielding the first crystal structures for pterosides, and three known pterosins, (2 S )-pterosin A, trans -pterosin C and cis -pterosin C. Rhedynosin C is the only example of the cyclic lactone pterosins with a keto group at position C-14. Six selected pterosins ((2 S )-pterosin A, (2 R )-pterosin B and trans -pterosin C) and associated glycosides ((2 S )-pteroside A, (2 R )-pteroside B and pteroside Z) were assessed for their anti-diabetic activity using an intestinal glucose uptake assay; all were found to be inactive at 300 μM. [ABSTRACT FROM AUTHOR]

Cretaceous fossils of derived leptosporangiate ferns (Polypodiales) are exceedingly rare yet they are needed to confirm the hypothesis of a Cretaceous diversification of polypod ferns as predicted by DNA-based divergence time estimates. Here we show that diverse polypod ferns existed in the mid-Cretaceous woodlands of Myanmar. We describe isolated sporangia with a vertical, broken annulus ring containing a differentiated stomium as well as distinguished pinnae fragments. Krameropteris resinatus gen. et sp. nov. is described based on a pinnae-fragment with free branched veins, exindusiate sori and polypod sporangia with trilete spores, and assigned to the early diverging polypod fern lineage Dennstaedtiaceae. Integration of the new fossil evidence in a phylogenetic framework provides support to the hypothesis of a Cretaceous diversification of polypod ferns. [ABSTRACT FROM AUTHOR]

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The article focuses on the revision to the taxonomy of the South American species of Hypolepis (Dennstaedtiaceae). It discusses the plant terrestrial, distribution, and ecology of several Hypolepis species including Hypolepis parallelogramma of Peru, Hypolepis paulistana of São Paulo, Brazil, and Hypolepis pedropaloensis of Colombia. Other species mentioned are Hypolepis poeppigii, Hypolepis pteroides, and Hypolepis rigescens.

The spore morphology and wall structure of Dennstaedtia species from the Phytogeographic Paranaense Province: Dennstaedtia cicutaria , D. cornuta , D. dissecta , D. globulifera , D. obtusifolia were studied using light microscopy (LM), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The spores are trilete, brown, triangular in polar view and plane-hemispheric to plane-convex in equatorial view. The exospore is homogeneous, with two layers. The perispore has an alveolar structure and is composed of one or two layers. The outer perispore surface bears the sculpture, which has elements of varied shapes (verrucae, ridges, reticles), an different sizes and fusion. This variation allows characterize species or groups of species. Three different types of perispore ornamentation can be found: 1. Verrucate with verrucae covered with rodlets; 2. Verrucate-rugate with verrucae and smooth ridges; 3. Reticulate. The spores constitute an important source of characters with a systematic value for the genus Dennstaedtia and they are a useful tool for the identification of herbarium samples. [ABSTRACT FROM AUTHOR]

Recent studies have transferred several species previously attributed to the fern genus Oenotrichia to other genera, and even out of the Dennstaedtiaceae to other families. However, the relationship of the type species, O. maxima from New Caledonia, has not previously been investigated using DNA sequences. With phylogenetic analyses of chloroplast DNA sequences, we verify the placement of Oenotrichia within the Dennstaedtiaceae. Moreover, O. maxima actually nests along with Leptolepia in a clade of Dennstaedtia. Dennstaedtia itself is non-monophyletic, with a second clade being more closely related to Microlepia. We outline what is required to resolve the generic taxonomy of this group. We also find that samples attributed to Saccoloma are polyphyletic, with some falling inside the Dennstaedtiaceae and others outside. [ABSTRACT FROM AUTHOR]

Los resultados de los estudios sobre morfogénesis de la fase sexual de Odontosoria schlechtendalii y O. scandens son presentados en este trabajo. En O. schechlechtendalii y O. scandens las esporas son triletes, no clorofílicas, carecen de perina, la exina es lisa, ligeramente granulada a retuculata y la germinación es tipo Vittaria. El patrón de desarrollo protálico es tipo Adiantum. Los gametófitos adultos son cordiforme espatulados, con la probable presencia de anteridiógenos en O. schlechtendalii, ambas especies son glabras. Los organos sexuales son del tipo común de los helechos leptosporangiados. Las primeras hojas aparecen a los 56-92 días de cultivo, cuyo pecíolo y lámina es angostamente dividida, con tricomas bifurcados y estomas anomocíticosThe results of morphogenesis studies of the sexual phase of Odontosoria schlechtendalii and O. scandens are presented in this paper. In O. schlechtendalii and O. scandens the spores are triletes, non-chlorophyllous, and germinación is of the Vittaria-type, devoid of perine, the exine is smoth and sometimes coarsely ridged to reticulate. The development pattern is of the Adiantum-type. The adult gametophyte is cordate-spathulate, with probable presence of anteridiogen in O. schlechtendalii, both species are glabrous. Sex organs are of the common type of the leptosporangiate ferns. The first leaves appeared after 56-92 days of culture, with petiole and plate divide narrow, trichomes bifurcate and stomate anomocytic

Dennstaedtia gracilis A. Rojas et Tejero (Dennstaedtiaceae) es aquí descrita e ilustrada como una especie nueva endémica de México. Pertenece al grupo de especies que presentan un ala dorsal en la costa de las pínnulas pero difiere por la combinación de caracteres como hojas más pequeñas, rizoma delgado, pínnulas deltado-lanceoladas y ápice de los segmentos lobulado.Dennstaedtia gracilis A. Rojas et Tejero (Dennstaedtiaceae) is herein describes and illustrated as a new species endemic to Mexico. Its belongs to the group of winged adaxial secondary costae species but it differs by the combination of caracters as smaller fronds, deltate pinnules and lobed segment apex.