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Premise: Up to half of tropical forest plant species grow on other plants. Lacking access to soils, vascular epiphytes have unique adaptations for mineral nutrition. Among the most distinctive is the tank growth form of certain large bromeliads, which absorb nutrients that are cycled by complex microbial communities in water trapped among their overlapping leaf bases. However, tanks form only after years of growth by juvenile plants, which must acquire nutrients differently. Understanding how nutrient dynamics change during tank bromeliad development can provide key insights into the role of microorganisms in the maintenance of tropical forest biodiversity. Methods: We evaluated variations in plant morphology, growth, foliar nitrogen physiology, and phyllosphere bacterial communities along a size gradient spanning the transition to tank formation in the threatened species Tillandsia utriculata. Results: Sequential morphological and growth phases coincided with the transition to tank formation when the longest leaf on plants was between 14 and 19 cm. Before this point, foliar ammonium concentrations were very high, but after, leaf segments absorbed significantly more nitrate. Leaf‐surface bacterial communities tracked ontogenetic changes in plant morphology and nitrogen metabolism, with less‐diverse communities in tankless plants distinguished by a high proportion of taxa implicated in ureolysis, nitrogen fixation, and methanotrophy, whereas nitrate reduction characterized communities on individuals that could form a tank. Conclusions: Coupled changes in plant morphology, physiology, and microbiome function facilitate the transition between alternative nutritional modes in tank bromeliads. Comparing bromeliads across life stages and habitats may illuminate how nitrogen‐use varies across scales. [ABSTRACT FROM AUTHOR]

Symbioses with fungi are important and ubiquitous on dry land but underexplored in the sea. As yet only one seagrass has been shown to form a specific root-fungus symbiosis that resembles those occurring in terrestrial plants, namely the dominant long-lived Mediterranean species Posidonia oceanica (Alismatales: Posidoniaceae) forming a dark septate (DS) endophytic association with the ascomycete Posidoniomyces atricolor (Pleosporales: Aigialaceae). Using stereomicroscopy, light and scanning electron microscopy, and DNA cloning, here we describe a novel root-fungus symbiosis in the Indo-Pacific seagrass Thalassodendron ciliatum (Alismatales: Cymodoceaceae) from a site in the Gulf of Aqaba in the Red Sea. Similarly to P. oceanica, the mycobiont of T. ciliatum occurs more frequently in thinner roots that engage in nutrient uptake from the seabed and forms extensive hyphal mantles composed of DS hyphae on the root surface. Contrary to P. oceanica, the mycobiont occurs on the roots with root hairs and does not colonize its host intraradically. While the cloning revealed a relatively rich spectrum of fungi, they were mostly parasites or saprobes of uncertain origin and the identity of the mycobiont thus remains unknown. Symbioses of seagrasses with fungi are probably more frequent than previously thought, but their functioning and significance are unknown. Melanin present in DS hyphae slows down their decomposition and so is true for the colonized roots. DS fungi may in this way conserve organic detritus in the seagrasses' rhizosphere, thus contributing to blue carbon sequestration in seagrass meadows. [ABSTRACT FROM AUTHOR]

The leaves of Thalassia testudinum provide an ideal substrate for the establishment of small-sized algae with different morphologies that are abundant and diverse. There are few studies on epiphytism in Mexico, and most of them are floristic lists. The objective of this study was to analyze the taxonomic and morphofunctional composition of epiphytes in three climatic seasons, and their relationship with the phorophyte T. testudinum in two localities, El Uvero and Santa Rosa, in the south of Quintana Roo; three transects and fifteen quadrants were set in June and December (2014) and April (2015). A total of 84 epiphytic species were identified: 27 corresponded to Cyanobacteria, 10 to Phaeophyceae, 9 to Chlorophyta, and 38 to Rhodophyta. The highest specific richness was observed in Santa Rosa (73 species). The dry and summer rains seasons share a higher number of species compared to the winter rainy season. The crusty algae Hydrolithon farinosum was the dominant and most persistent species; in addition, filamentous algae presented great specific richness and coverage due to their morphology and reproductive strategies, which allowed them to successfully establish themselves on the phorophyte. This is related to the ecological succession of the epiphytes and seagrass phenology. [ABSTRACT FROM AUTHOR]

Abstract Epiphytes represent approximately 10% of vascular plants, or 25,000 species distributed across 84 families. Water deficit is the greatest challenge faced by epiphytes, resulting in anatomical strategies aimed at maximizing water usage and minimizing water loss. This study aimed to characterize the leaf blade anatomy of 40 species of vascular epiphytes occurring in a cloud forest of the Brazilian Atlantic Forest and assess how leaf anatomy is related to the epiphytic life form. Samples were collected, fixed, dehydrated with ethanol, and embedded in paraffin for sectioning using a microtome or freehand technique. Some samples were dissociated for epidermal observation. A clustering analysis (using UPGMA) was conducted using a presence/absence matrix of 16 anatomical characters. The results showed that species within this functional group exhibit different leaf blade anatomical characteristics, which may or may not be adaptive to epiphytism. However, despite the occurrence of some characteristics such as stomata at the same level as other epidermal cells, thick cuticle, fibers, hypodermis, and homogeneous chlorophyllous parenchyma in 50% or more of the species, there is no set of anatomical characteristics that can be used to define an epiphyte.

Epiphytes are considered indicators of forest ecological integrity, but the factors that explain their abundance are still not well understood. We here evaluated tree colonization by epiphytes in old-growth monospecific reforestation stands of Astronium urundeuva (M.Allemão) Engl. (Anacardiaceae) and Eucalyptus saligna Sm. (Myrtaceae), in comparison to a neighbor seasonal tropical forest fragment under similar environmental conditions. In each forest type, we identified and measured all trees (planted and colonizers) from 5-cm stem diameter in five 200 m² plots and quantified all vascular epiphytes per tree. Tree species were categorized by bark roughness, canopy deciduousness and growth rate. The abundance of epiphytes and the frequency of host trees were higher in the A. urundeuva plantation than in the native forest, with the E. saligna stand in an intermediate position. Also, we found that host traits influenced the abundance of epiphytes in their trunks. Host trees had average stem perimeter and height both higher than non-hosts, which indicates that colonization is more likely to occur in older trees. The average abundance of epiphytes per tree was higher in species with rough bark, but no relationship was found with canopy deciduousness or tree growth rate. We evidenced, therefore, that forest plantations, even if monospecific, can provide habitat for epiphytes. However, at community level, colonization success, either in native or restored forest, depends on the relative abundance of species whose bark type favors epiphytes establishment. [ABSTRACT FROM AUTHOR]

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Abstract Vascular epiphytes stand out in tropical forests in terms of diversity. However, no comprehensive review of the group in the Amazon region has been performed so far. We carried out a literature review on the scientific knowledge of vascular epiphytes in the Amazon aiming to identify the main gaps, limitations and perspectives for studies on the subject. Searches were conducted in Google Scholar, Scopus and Web of Science using inclusion and exclusion criteria. 291 articles published in the period 1933-2022, mostly the 21st century, were included in the review. Brazil was the most studied country. However, knowledge gaps were found in regions located in the Brazilian arc of deforestation as well as in areas of Bolivia, Guyana, French Guiana and Suriname. There was a predominance of studies related to the floristics, systematics and biogeography of spermatophytes and ferns, focusing on the diversity and taxonomy of certain families (e.g. Orchidaceae). However, we found gaps for more comprehensive research, considering population dynamics, dominance (biomass), guidelines for evaluation of epiphyte and systematization of data for Amazon. We indicate the need of studies focused on ecology, floral and reproductive biology, biochemistry, phytochemistry, anatomy and physiology. Future research should also consider the impacts of current trends in deforestation and climatic changes on the diversity of vascular epiphytes in the Amazon.

Vascular epiphytes, plants that evolve on other plant species, are considered bioindicators of environmental quality. Current study surveys epiphytes at the Serra das Araras ecological station, located in the savanna biome within the Amazon-Pantanal transition area, and evaluates the species’ potential as moisture bioindicators. Three transects were planned, parallel to the Camarinha stream and close to the Miranda stream, both within the Upper Paraguay Basin, with ten plots each, totaling 30 plots of 10 x 3 m. Variance analysis (Kuskall-Wallis) of abundance among transects, linear regression analysis with abundance and richness data were performed as a function of water body distance and Kernel density analysis. Six species of epiphytes were reported, with special reference to Phlebodium decumanum (Willd.) J.Sm. and Vanilla sp. Further, 19.6% of 143 phorophytes sampled were confirmed by epiphytes, of which 27 were Attalea speciosa Mart. ex Spreng. The transect close to the water bodies showed abundance with significant difference (p = 0.004) to transect 3. Fifteen of the 30 plots sampled had epiphytes and regression analysis showed a significant decrease for richness (p =0.0003, R-adjusted = 0.372) and abundance (p = 0.042 R-adjusted = 0.139) as a function of the distance of the streams, following what has been reported in density analysis, with the highest concentration near the watercourses. Human intervention may have conditioned a low richness rate of epiphytes. The occurrence of these species is correlated with that of phorophyte Attalea speciosa established preferably in humid areas. Consequently, epiphytes may be bioindicators of the region´s environmental conditions. [ABSTRACT FROM AUTHOR]

Seaweeds are macroscopic forms of phylogenetically diverse assemblage of marine algae that grow in oceans, thriving among profoundly harsh environmental conditions. They are cultivated in many maritime nations primarily for edible applications; besides hydrocolloid extraction is the second largest domain of utility for this renewable biomass. The farming practices have been traditionally evolved in different Southeast Asian countries. Nevertheless, advancement in the knowledge about their life‐history traits and control over reproduction has paved ways for commencement of large‐scale commercial farming. Food and Agriculture Organisation of United Nations reported the availability of 35.8 million tons of seaweed biomass globally of which 97% accounted for farming. Although cultivation is on the rise due to relevant to social gains, epiphytic infestation, diseases and grazing have been identified as leading causes that result in substantially lower yield, deteriorated quality of product and skewed economics. Epiphytes may considerably impact the interaction of seaweed hosts with other beneficial communities also. Epidemiological studies in natural seaweed populations are scarce and this makes the understanding of the cross‐talk involving host specificity, and their role obscure. An overview of the diversity of epiphytes, understanding of mechanism of action, factors responsible, chemistry behind their interaction will help in deciphering the solutions to overcome infestation. A comprehensive report of seaweed epiphytism, diseases and grazing from the aspects of host–epiphyte interaction and their resultant consequences is presented along with the studies on economic impacts. The role of multi‐omics approaches in delineating seaweed epiphytic interactions is also included. [ABSTRACT FROM AUTHOR]

Hohenbergia burle‐marxii is one of the rarest species of Hohenbergia (Bromeliaceae), until recently known only by the holotype and its clones. The species had been recorded only once in an imprecise locality in Bahia's south region. After extensive field work we refound the species and we here present a new geographic range of Hohenbergia burle‐marxii, at the same time adding information about its morphology and ecological traits, including a map and photographs of living plants. [ABSTRACT FROM AUTHOR]

Epiphytic lifestyles have evolved independently in ecologically, morphologically, and taxonomically diverse plant species. Although this adaptation is widespread among angiosperms, it is only known to have arisen in a single gymnosperm species, Zamia pseudoparasitica (Cycadophyta). Zamia pseudoparasitica is endemic to the mountains of Western Panama, and little is known about the ecology of this unusual cycad. Here, we provide the first report of a potential seed disperser of Z. pseudoparasitica. Between late October 2019 and March 2020, we conducted arboreal camera trapping at three sites along the Talamanca Cordillera in Western Panama, yielding an accumulated survey effort of 271 camera days. Weekly direct observations were also performed using handheld binoculars at one site. Arboreal camera trapping revealed at least seven mammal species that visit this epiphytic cycad. At all three sites, the Northern olingo (Bassaricyon gabbii) was seen visiting individuals of Z. pseudoparasitica repeatedly, both while cones were closed and after they had opened. We estimated the time‐varying intensity of the visits throughout our sampling and used mixed models to compare the length of visits when cones were closed versus when they were open. Both duration and time‐varying intensity of visits increased after cones had opened and we documented Northern olingo removing and carrying away seeds. We also observed predation by the yellow‐eared toucanet (Selenidera spectabilis) which picked and destroyed mature Z. pseudoparasitica seeds. These results suggest that the Northern olingo could be an important seed dispersal agent for this rare epiphytic gymnosperm. [ABSTRACT FROM AUTHOR]

Summary: Approximately 10% of vascular plants are epiphytes and, even though this has long been ignored in past research, are able to interact with a variety of fungi, including mycorrhizal taxa. However, the structure of fungal communities on bark, as well as their relationship with epiphytic plants, is largely unknown.To fill this gap, we conducted environmental metabarcoding of the ITS‐2 region to understand the spatial structure of fungal communities of the bark of tropical trees, with a focus on epiphytic orchid mycorrhizal fungi, and tested the influence of root proximity.For all guilds, including orchid mycorrhizal fungi, fungal communities were more similar when spatially close on bark (i.e. they displayed positive spatial autocorrelation). They also showed distance decay of similarity with respect to epiphytic roots, meaning that their composition on bark increasingly differed, compared to roots, with distance from roots.We first showed that all of the investigated fungal guilds exhibited spatial structure at very small scales. This spatial structure was influenced by the roots of epiphytic plants, suggesting the existence of an epiphytic rhizosphere. Finally, we showed that orchid mycorrhizal fungi were aggregated around them, possibly as a result of reciprocal influence between the mycorrhizal partners. [ABSTRACT FROM AUTHOR]

Epiphytism is a common phenomenon in macroalgal aquaculture worldwide. This problem can affect the productivity and quality of the farmed species which may have socioeconomic consequences for the human communities that depend on this activity. In southern Chile, the aquaculture of the red macroalga Agarophyton chilense in the area of Maullín River has suffered losses in local production (> 90%) due to the proliferation of the filamentous green epiphyte Rhizoclonium sp. This epiphyte becomes entangled with A. chilense fronds, diminishing its quality and preventing its sale as raw material. Thus, the aim of this study was to investigate the effects of light intensity (90 and 180 μmol photons m−2 s−1) on the competitive interaction between the epiphyte Rhizoclonium sp. and the basiphyte A. chilense co-cultured at different initial biomass proportions in a replace series experiment. At the end of the experiment, the presence of Rhizoclonium sp. did not affect negatively the growth of A. chilense, but both species showed stress responses (i.e. reduced Fv/Fm and C:N ratio, suggesting nutrient limitation) in co-culture compared with monocultures. The epiphyte-basiphyte interaction was not modulated by light availability at any initial co-culture proportion and could have been related to nutrient availability during experimentation. Using the replacement series approach, an interspecific competition was observed at all initial co-culture proportion under 180 μmol photons m−2 s−1 while competition was found at the initial co-culture 1:1 under 90 μmol photons m−2 s−1. Our results suggest that the interaction in co-culture between both A. chilense and Rhizoclonium sp. seems to be regulated by nutrient availability as well as it demands utilization rather than light availability. [ABSTRACT FROM AUTHOR]

• The canopy presents higher richness compared to the trunk. • The composition exhibited similarity both among the vegetation types Dwarf cloud forest and the strata. • The vegetation type with more wind incidence and short phorophytes presented lower richness. • The stratification of the Bromeliaceae and Polypodiaceae families played a significant role in the species distribution pattern. Vascular epiphytes are plants that grow on phorophytes, and their distribution may vary both horizontally and vertically. Understanding the factors shaping epiphyte distribution and their relationship with alpha and beta diversities is crucial for understanding richness and composition patterns. We investigated alpha and beta diversity variation in the vertical and horizontal stratification of epiphyte communities across different vegetation types in a dwarf cloud forest. Twenty-four 20 × 10 m plots were established in three vegetation types defined by distinct soil characteristics, different phorophyte height and differences in tree species composition in Parque Estadual do Ibitipoca, Minas Gerais, Brazil. Phorophytes were divided into four strata: (A) base of the trunk, (B) lower trunk, (C) inner canopy, and (D) outer canopy. Alpha and beta diversity analyses were performed for each site. We found a reduced stratification in the area, indicating minimal composition differences between the strata. However, the canopy exhibited greater species richness than the trunk. Vegetation types F1 and F2 displayed higher richness compared to F3. Orchidaceae was the richest family overall, while Bromeliaceae and Polypodiaceae were more frequent. Holoepiphytes were highly representative, demonstrating consistent patterns of richness, composition, and dispersion, with anemochorous species being the most abundant. This study highlights the unique patterns of epiphyte stratification, emphasizing the importance of biotic and abiotic characteristics in colonization processes. Despite the low canopy of the forest, the non-uniformity in stratification demonstrates that formation characteristics, such as height, play a significant role in shaping epiphyte richness and composition patterns. [ABSTRACT FROM AUTHOR]

Epiphytes are common in the canopy of temperate and tropical forests, where they substantially contribute to species diversity and to key ecosystem processes. However, little is known about the effects caused by deforestation on this group of species, especially in northeastern Brazil, an area experiencing intense anthropogenic pressure. This study aimed to evaluate the effect of environmental variables on the structure of assemblies of vascular epiphytes in a fragment of open ombrophilous forest, Areia, northeastern Brazil. Sixty 10 × 10 m sampling plots were installed to cover different environments within the fragment. The relationship between environmental variables and species composition was evaluated by means of a generalized linear mixed model. The composition of assemblies of epiphytes differed with respect to distance from the edge and luminosity. In the study area, deforestation led to a change in the composition of epiphytic species both at the edge and the interior of the fragment.

Abstract: Seaweeds are able to modify the chemical environment at their surface, in a micro‐zone called the diffusive boundary layer (DBL), via their metabolic processes controlled by light intensity. Depending on the thickness of the DBL, sessile invertebrates such as calcifying bryozoans or tube‐forming polychaetes living on the surface of the blades can be affected by the chemical variations occurring in this microlayer. Especially in the context of ocean acidification (OA), these microhabitats might be considered as a refuge from lower pH, because during the day photosynthesis temporarily raises the pH to values higher than in the mainstream seawater. We assessed the thickness and the characteristics of the DBL at two pH levels (today's average surface ocean pH 8.1 and a reduced pH predicted for the end of the century, pH 7.7) and seawater flows (slow, 0.5 and fast, >8 cm/s) on Ecklonia radiata (kelp) blades. Oxygen and pH profiles from the blade surface to the mainstream seawater were measured with O2 and pH microsensors for both bare blades and blades colonized by the bryozoan Membranipora membranacea. The DBL was thicker in slow flow compared with fast flow and the presence of bryozoans increased the DBL thickness and shaped the DBL gradient in dark conditions. Net production was increased in the low pH condition, increasing the amount of oxygen in the DBL in both bare and epiphytized blades. This increase drove the daily pH fluctuations at the blade surface, shifting them towards higher values compared with today's pH. The presence of bryozoans led to lower oxygen concentrations in the DBL and more complex pH fluctuations at the blade surface, particularly at pH 7.7. Overall, this study, based on microprofiles, shows that, in slow flow, DBL microenvironments at the surface of the kelps may constitute a refuge from OA with pH values higher than those of the mainstream seawater. For calcifying organisms, it could also represent training ground for harsh conditions, with broad daily pH and oxygen fluctuations. These chemical microenvironments, biologically shaped by the macrophytes, are of great interest for the resilience of coastal ecosystems in the context of global change. A plain language summary is available for this article. [ABSTRACT FROM AUTHOR]

In a living tree crown, the surface expands from year to year and the limbs of the tree thicken, as a consequence of primary and secondary growth. An epiphytic plant fixed on a bark surface is thus subject to constant and, at times, rapid successional change, to which the epiphyte must acclimate or die. These changes concern physical and chemical development in the bark substrate and changes in microclimatic conditions. Thus, the width of the tolerance range of an epiphytic species in principle defines its typical longevity. Epiphytes are distributed in a non-random fashion with respect to crown part occupied, the zone of habitation being delimited by the youngest crown position offering conditions for establishment and the position preventing further survival of the epiphytic species in question. The orchid life cycle is crucially dependent on other organisms, such as pollinating animals and symbiotic fungi, but the relationship between epiphytic orchid and phorophyte tree is currently receiving the least attention, despite the likely relevance for conservation of rare and threatened orchid species. Although many correlative studies have recorded occurrence of mature epiphytic orchids, the dynamics created by the growth of the phorophyte are often disregarded. We call for more experimental approaches, such as transplantation studies of seeds and seedlings, to reveal the still largely unknown mechanisms by which orchid distribution is biased towards certain phorophyte species, age stages and crown positions. We provide a compilation of noteworthy cases that could serve as starting points for studies into bias mechanisms. [ABSTRACT FROM AUTHOR]

The diversity of montane environments is dictated by a variety of environmental conditions. Parque Estadual do Ibitipoca is located in the Serra da Mantiqueira, between ~1,000–1,800 m, and harbors approximately 300 ha of cloud forests. The composition of vascular epiphytes was determined by analyzing data from expeditions conducted between July 2014 and July 2015, and specimens deposited at herbaria. The 224 species were distributed into 82 genera of which Pleurothallis s.l. was the richest (13 spp.) and 23 families of which Orchidaceae was the richest (87 spp.). This richness corresponds to approximately 9.5% of the vascular epiphytic flora of the Atlantic Forest concentrated in an area that comprises 0.00085% of this phytogeographic domain, which represents one of the largest diversities ever sampled in the Brazilian Atlantic Forest. This fact is more relevant given that 13 species are threatened at the country level and 23 at the state level. [ABSTRACT FROM AUTHOR]

Vascular epiphytes constitute a life form that is important to maintaining the biological diversity of forest ecosystems, because they provide food resources and specialized microenvironments for fauna in the forest canopy. This study aimed to describe the floristic composition and ecological aspects of vascular epiphytes occurring in the restingas (coastal woodlands) within the Algodoal-Maiandeua Environmentally Protected Area, located in the municipality of Maracanã, in the state of Pará, Brazil. We sampled five 50 × 50 m plots (three in dry restinga forest and two in floodplain restinga forest), the sampled area therefore totaling 1.25 ha. In the plots sampled, vascular epiphytes were identified and described according to their frequency, abundance, importance value (IV), functional group and vertical distribution (trunk, lower crown or upper crown of the host). For both forest types, we identified 477 individuals belonging to five families, nine genera and 11 species. The most species-rich families were Araceae and Orchidaceae. The species with the highest density, frequency and IV were the secondary hemiepiphytes Philodendron acutatum, Anthurium pentaphyllum and Philodendron muricatum, collectively accounting for 92.1% of all sampled individuals. The true epiphytes predominated. Epiphytic species richness and abundance was greater on the host trunk than in the lower or upper crown. The seasonal climate and structure of the forest favored greater abundance of secondary hemiepiphytes and a higher frequency of epiphytes on the trunks of their hosts.

Ascophyllum nodosum is commercially harvested in the southwestern parts of Nova Scotia. Here the hypothesis is evaluated that harvesting results in a reduction in the abundance of Vertebrata lanosa, an obligate epiphyte of A. nodosum. Sampling at 10 harvested and 16 non-harvested sites showed that percent cover and frequency were significantly lower at harvested sites (i.e. 5.4 ± 4.0 and 0.6 ± 0.7% cover, and 61 ± 24 and 21 ± 18% frequency for non-harvested and harvested sites, respectively). Vertebrata lanosa is suggested as a useful indicator of ecological integrity at harvesting sites. [ABSTRACT FROM AUTHOR]

Epiphytic diatoms on seaweeds and seagrasses were collected from tropical regions in the western Pacific Ocean (i.e., Siladen Island, Celebes Sea, Indonesia; Guam; Palau). Fifteen species ofDiploneisare described in detail with light and scanning electron microscopy including six species new to science,D.cerebrum,D. claustra, D.craticula,D.crispa,D.rimosaandD.weissflogiopsis. Valve structure inDiploneisis particularly complicated, and two new distinctive structures are described for the first time: (1) central external raphe endings with flaps or rolled flaps and (2) internal globular papillae near the marginal ends of the virgae. In addition, we confirm that openings on the inner surface of the longitudinal canals are of taxonomic value. The structural complexities encountered inDiploneisrequire the study of a great many more taxa before a meaningful revision of the genus can be undertaken. Its diversity in warm waters is a rich resource for newDiploneistaxa to further our understanding of the genus. [ABSTRACT FROM AUTHOR]

We investigated the distribution of epiphytic macroalgae on the thalli of their hosts at eight localities along the southeastern coast of Cuba between June 2010 and March 2011. We divided he epiphytes in two groups according to their distribution on the host: those at the base of the thallus and those on its surface. We determining the dissimilarity between the zones and the species involved. We identified 102 taxa of epiphytic macroalgae. There were significant differences between the two zones. In 31 hosts, the number of epiphytes was higher on the surface of the thallus, whereas the number of epiphytes was higher at the thallus base in 25 hosts, and the epiphytes were equally distributed between the two zones in five hosts (R=−0.001, p=0.398). The mean dissimilarity between the two zones, in terms of the species composition of the epiphytic macroalgae, was 96.64%. Hydrolithon farinosum and Polysiphonia atlantica accounted for 43.76% of the dissimilarity. Among macroalgae, the structure of the thallus seems to be a determinant of their viability as hosts for epiphytes.

The species-rich genus Peperomia (Black Pepper relatives) is the only genus among early diverging angiosperms where epiphytism evolved. The majority of fruits of Peperomia release sticky secretions or exhibit hook-shaped appendages indicative of epizoochorous dispersal, which is in contrast to other flowering plants, where epiphytes are generally characterized by fruit morphological adaptations for anemochory or endozoochory. We investigate fruit characters using Cryo-SEM. Comparative phylogenetic analyses are applied for the first time to include life form and fruit character information to study diversification in Peperomia. Likelihood ratio tests uncover correlated character evolution. We demonstrate that diversification within Peperomia is not homogenous across its phylogeny, and that net diversification rates increase by twofold within the most species-rich subgenus. In contrast to former land plant studies that provide general evidence for increased diversification in epiphytic lineages, we demonstrate that the evolution of epiphytism within Peperomia predates the diversification shift. An epiphytic-dependent diversification is only observed for the background phylogeny. An elevated frequency of life form transitions between epiphytes and terrestrials and thus evolutionary flexibility of life forms is uncovered to coincide with the diversification shift. The evolution of fruits showing dispersal related structures is key to diversification in the foreground region of the phylogeny and postdates the evolution of epiphytism. We conclude that the success of Peperomia, measured in species numbers, is likely the result of enhanced vertical and horizontal dispersal ability and life form flexibility but not the evolution of epiphytism itself.

Los cáudices de los helechos arborescentes presentan condiciones particulares que favorecen el establecimiento de epífitas. En este trabajo se estudiaron los helechos que crecen sobre Alsophila setosa Kaulf. (Cyatheaceae, Pteridophyta) en la provincia de Misiones. Se encontraron 21 especies, que se agruparon en 10 géneros y 5 familias. La familia más diversa fue Polypodiaceae, con 8 especies, y los géneros mejor representados fueron Asplenium (6) y Pecluma (4). Se presenta una clave para la identificación de los taxa involucrados. La cantidad de especies epífitas encontradas sugiere que Alsophila setosa juega un papel importante como reservorio de biodiversidad en el bosque atlántico.Epiphyte ferns on Alsophila setosa (Cyatheaceae, Pteridophyta) from Misiones province, Argentina. Trunks of tree ferns offer especially distinctive substrates to support epiphytes. In this paper, ferns that grow on Alsophila setosa Kaulf. from Misiones were studied. A total of 21 species, from 10 genera and 5 families, were recorded. Polypodiaceae (8) had greater specific diversity. Richest genera were Asplenium (6) and Pecluma (4). A key is presented to identify the taxa involved. The high epiphytic diversity found suggests that Alsophila setosa plays an important role as a biodiversity reservoir in the Atlantic forest.

Considering that the root structure of the Brazilian genera belonging to the Catasetinae subtribe is poorly known, we describe the roots of twelve representatives from this subtribe. For anatomical analysis, the roots were fixed in FAA 50, preserved in ethanol 70% and sectioned at its medium region using razor blades. The sections were stained with 0.05% astra blue and safranin and mounted in glycerin. For the identification of starch we used Lugol's solution; for lignin, floroglucin chloridric; for lipids, Sudan III, and for flavanoids, potassium hydroxide. The relevant aspects were registered using a digital camera joined with an Olympus microspope (BX51 model). The structural similarities of all roots support the placement of the subtribe Catasetinae into the monophyletic tribe Cymbidieae. Some root features are restricted to one or two taxa and can be useful in the systematics of the subtribe. For example, the occurrence of flavonoidic crystals characterizes the genera Catasetum and Cychnodes, and the number of the velamen layers and the shape of the epivelamen cells are useful to confirm the taxonomic position of Clowesia amazonica. The presence of velamen and flavonoidic crystals was interpreted as an adaptation to the epiphytic habit.Considerando que a estrutura das raízes de gêneros brasileiros pertencentes à subtribo Catasetinae é pouco conhecida, descrevemos as raízes de doze representantes desta subtribo. Para análise anatômica, as raízes foram fixadas em FAA 50, preservadas em álcool 70% e seccionadas na sua região média usando lâminas de barbear. Os cortes foram corados com astra blue e Safrablau 0,05% e montados em glicerina. Para a identificação do amido, utilizou-se a solução de Lugol; da lignina, floroglucina clorídrica, dos lipídios, Sudan III e dos flavonóides, hidróxido de potássio. Os aspectos relevantes foram registrados usando câmera digital acoplada a um microscópio Olympus (modelo BX51). As semelhanças estruturais observadas entre todas as raízes estudadas confirmam a inclusão da subtribo Catasetinae na tribo monofilética Cymbidieae. Algumas características radiculares são restritas a um ou dois táxons e podem ser úteis na taxonomia da subtribo. Por exemplo, a ocorrência de cristais flavonoídicos caracteriza os gêneros Catasetum e Cychnodes e o número de camadas do velame associado à forma das células do epivelame são úteis para confirmar a posição taxonômica de Clowesia amazônica. A presença de velame e de cristais flavonoídicos foi interpretada como adaptações ao hábito epifítico.

Informações sobre a diversidade no nível de espécie oferecem subsídios importantes para o desenvolvimento sustentável e a conservação biológica. Neste contexto, estudos com Bromeliaceae merecem destaque, especialmente porque o grupo é importante ecologicamente, mas ainda pouco conhecido na Região Norte. Neste trabalho, foram demarcadas duas parcelas de 100 m x 100 m em uma floresta de várzea localizada na Área de Proteção Ambiental Ilha do Combu, em Belém, Estado do Pará. Cada parcela foi subdividida em oito parcelas de 50 m x 50 m, tendo todas as espécies e espécimes de bromeliáceas epífitas registradas e quantificadas. A diversidade do grupo foi calculada utilizando o índice de Shannon-Wiener. Foram registrados 1.339 indivíduos pertencentes a oito espécies e quatro gêneros. Tillandsia e Aechmea apresentaram maior riqueza. A diversidade de espécies na área foi de H= 1,10, apresentando dominância acentuada de muitos indivíduos em poucas espécies.Information about diversity at the species level offers data for sustainable development and biological conservation. In this context, studies about Bromeliaceae are noteworthy, especially because this group is ecologically important and poorly known in the North Region of Brazil. In this study, two grids (100 m x 100 m) were delineated in a floodplain forest in the environmental protection area of Combu Island, Belém, Pará, Brazil. The grids were subdivided into eight grids of 50 m x 50 m, and all species and individuals of epiphytic Bromeliaceae were recorded and quantified. The diversity was calculated using the Shannon-Wiener index. A total of 1,339 individuals, belonging to eight species and four genera were recorded. Tillandsia and Aechmea presented the greatest richness. The diversity of species was H= 1.10, presenting sharp dominance of many individuals of few species.

The review provides the results of publications devoted to ecological characteristics of orchids, particularly to epiphytism, structural and functional adaptations related with this life form, as well as to relationship of orchids with mycorrhizal fungi. Elucidation of this subject is a theoretical background for interpretation of the results of orchids investigation under glasshouse conditions aimed at ex situ conservation.

O presente estudo foi realizado em uma área de ecótono de aproximadamente 30 hectares entre Floresta Estacional Semidecidual e Floresta Ombrófila Mista, localizada na Capela do Calvário, município de Campo Mourão, PR. Para a análise fitossociológica foram selecionados 80 forófitos. No levantamento total foram encontradas 61 espécies, 39 gêneros e 13 famílias de epífitas (10 de Pteridófitas e 51 de Magnoliófitas). As famílias mais ricas foram: Orchidaceae (38%), Bromeliaceae e Polypodiaceae (13%), Cactaceae (11%) e Piperaceae (8%), que juntas compõem 83% das espécies amostradas. Os gêneros Tillandsia (Bromeliaceae) e Peperomia (Piperaceae) foram os mais ricos, com cinco espécies. A anemocoria foi constatada em 67% das espécies e 86% foram classificadas como holoepífitas verdadeiras. Das 61 espécies inventariadas, 43 ocorreram nas áreas de amostragem, sendo cinco em maior freqüência: Microgramma squamulosa, Pleopeltis angusta, Tillandsia loliacea, Tillandsia recurvata e Pecluma sicca. O índice de Shannon (H’) registrado para a área foi de 3,175 e a equabilidade (J) 0,863. Foram encontradas nove espécies epifíticas restritas a apenas um forófito. Microgramma squamulosa foi a espécie mais importante em toda área amostral. O trecho de vegetação em área de interflúvio, por apresentar estágio avançado de desenvolvimento, teve riqueza superior à área de vegetação ribeirinha.This study was conducted in a transition area of approximately 30 hectares between Semideciduous Forest and Araucaria Forest located in the Capela do Calvário, at Campo Mourão, Paraná. For the phytosociological analysis 80 phorophytes were selected. The survey found 61 species, 39 genera and 13 families of epiphytes (10 pteridophytes and 51 magnoliophytes). The richest families were: Orchidaceae (38%), Bromeliaceae and Polypodiaceae (13%), Cactaceae (11%) and Piperaceae (8%), which together make up 83% of the sampled species. Tillandsia (Bromeliaceae) and Peperomia (Piperaceae) were the richest genera, each with five species. Anemochory was found in 67% of the species and 86% were classified as true holoepiphytes. Of the 61 species listed, 43 occurred in the sample area; the following five had the highest frequency: Microgramma squamulosa, Pleopeltis angusta, Tillandsia loliacea, Tillandsia recurvata and Pecluma sicca. The Shannon Index (H’) recorded for the area was 3.175 and evenness (J) 0.863. Nine epiphytic species were restricted to just one phorophyte. Microgramma squamulosa was the most important species over the entire sample area. The vegetation of the interfluvial area, in an advanced stage of development, was richer than the riverside vegetation.

Este estudio documenta la diversidad, distribución altitudinal y geografía de Araceae en la región de Los Tuxtlas, Veracruz. Se escogió un transecto altitudinal en bosque tropical perennifolio y bosque mesófilo de montaña bien conservado desde los 100 m de altitud hasta la cima del volcán San Martín Tuxtla a los 1 700 m. En cada cota altitudinal de 100 m de elevación se realizaron muestreos en 3-4 parcelas de 400 m². El listado de aráceas presentado para la región de la Reserva de la Biosfera Los Tuxtlas se basa en datos propios, complementado con información de listas publicadas, bases de datos y revisión de herbarios. Se registraron 34 especies representadas en 9 géneros, de las cuales 5 son endémicas de México. Las aráceas (hemi-) epífitas representan aproximadamente el 11% de la flora epifítica de la Estación de Biología Tropical Los Tuxtlas. A lo largo del gradiente altitudinal se observó un descenso constante del número de especies respecto al incremento de la altitud. El hallazgo de 3 nuevos registros de aráceas para la región de Los Tuxtlas y el estado de Veracruz demuestran que la realización de más inventarios florísticos sería importante.This study documents the diversity, altitudinal and geographical distribution of Araceae in the region of Los Tuxtlas, Veracruz. An altitudinal transect was selected in mature tropical rain and cloud forest from 100 m elevation to the summit of the San Martín Tuxtla volcano at 1 700 m. In each range of 100 m elevation we carried out inventories of Araceae in 3-4 plots of 400 m². The list of aroids presented for the region of the Reserva de la Biosfera Los Tuxtlas is based on our own data, supplemented with information from published sources, data bases and revision of herbarium specimens. We recorded a total of 34 species in 9 genera, of which 5 are endemic to Mexico. The (hemi-) epiphytic aroids represent about 11% of the epiphytic flora at the Biological Research Station Los Tuxtlas. A constant decline of the number of species was observed with increasing elevation along the altitudinal gradient. The discovery of 3 new records of aroid species for the region of Los Tuxtlas and the state of Veracruz shows that it would be important to carry out more floristic inventories.

ABSTRACT Only a few studies regarding vascular epiphytes have been conducted in mixed ombrophilous forests (MOF) in Serra da Mantiqueira, a mountainous environment in the Brazilian Atlantic Forest, where the relationships of epiphytic flora with other physiognomies are unknown. This study aimed to survey the epiphytes of a MOF remnant located in Serra da Mantiqueira, and to analyze the floristic relationships with ombrophilous forests of the Southern and Southeastern regions of Brazil. The checklist was compared with 51 other areas composed of ombrophilous forests and/or ecotones with other physiognomies using UPGMA (with Sørensen index), and canonical correspondence analysis (CCA). We recorded 138 species, and Orchidaceae and Polypodiaceae were the richest families (51 and 23 species, respectively). The UPGMA showed the importance of physiognomy and elevation in the floristic relationships, and CCA reinforced the influence of elevation, in addition to the shortest distance to the ocean and minimum annual temperature; however, in this analysis, the physiognomies showed little influence on the relationships. The epiphytic flora of MOF of Southern and Southeastern regions of Brazil has different relationships compared with the data available for shrubs and trees, suggesting a greater importance of phorophytic species than geographical distance and, to some extent, environmental variables.

The species-rich genus Peperomia (Black Pepper relatives) is the only genus among early diverging angiosperms where epiphytism evolved. The majority of fruits of Peperomia release sticky secretions or exhibit hook-shaped appendages indicative of epizoochorous dispersal, which is in contrast to other flowering plants, where epiphytes are generally characterized by fruit morphological adaptations for anemochory or endozoochory. We investigate fruit characters using Cryo-SEM. Comparative phylogenetic analyses are applied for the first time to include life form and fruit character information to study diversification in Peperomia. Likelihood ratio tests uncover correlated character evolution. We demonstrate that diversification within Peperomia is not homogenous across its phylogeny, and that net diversification rates increase by twofold within the most species-rich subgenus. In contrast to former land plant studies that provide general evidence for increased diversification in epiphytic lineages, we demonstrate that the evolution of epiphytism within Peperomia predates the diversification shift. An epiphytic-dependent diversification is only observed for the background phylogeny. An elevated frequency of life form transitions between epiphytes and terrestrials and thus evolutionary flexibility of life forms is uncovered to coincide with the diversification shift. The evolution of fruits showing dispersal related structures is key to diversification in the foreground region of the phylogeny and postdates the evolution of epiphytism. We conclude that the success of Peperomia, measured in species numbers, is likely the result of enhanced vertical and horizontal dispersal ability and life form flexibility but not the evolution of epiphytism itself. [ABSTRACT FROM AUTHOR]

Background: The seagrass Posidonia oceanica L. Delile, commonly known as Neptune grass, is an endemic species of the Mediterranean Sea. It hosts a distinctive and diverse epiphytic community, dominated by various macroalgal and animal organisms. Mediterranean bryozoans have been extensively studied but quantitative data assessing temporal and spatial variability have rarely been documented. In Lepoint et al. (2014a, b) occurrence and abundance data of epiphytic bryozoan communities on leaves of P. oceanica inhabiting Revellata Bay (Corsica, Mediterranean Sea) were reported and trophic ecology of Electra posidoniae Gautier assessed. New information: Here, metadata information is provided on the data set discussed in Lepoint et al. (2014a) and published on the GBIF portal as a sampling-event data set: http://ipt.biodiversity.be/resource?r=ulg_bryozoa&v=1.0). The data set is enriched by data concerning species settled on Posidonia scales (dead petiole of Posidonia leaves, remaining after limb abscission). [ABSTRACT FROM AUTHOR]

Using a time-calibrated phylogenetic hypothesis including 768 Gesneriaceae species (out of ∼3300 species) and more than 29,000 aligned bases from 26 gene regions, we test Gesneriaceae for diversification rate shifts and the possible proximal drivers of these shifts: geographic distributions, growth forms, and pollination syndromes. Bayesian Analysis of Macroevolutionary Mixtures analyses found five significant rate shifts in Beslerieae, core Nematanthus, core Columneinae, core Streptocarpus, and Pacific Cyrtandra. These rate shifts correspond with shifts in diversification rates, as inferred by Binary State Speciation and Extinction Model and Geographic State Speciation and Extinction model, associated with hummingbird pollination, epiphytism, unifoliate growth, and geographic area. Our results suggest that diversification processes are extremely variable across Gesneriaceae clades with different combinations of characters influencing diversification rates in different clades. Diversification patterns between New and Old World lineages show dramatic differences, suggesting that the processes of diversification in Gesneriaceae are very different in these two geographic regions. [ABSTRACT FROM AUTHOR]

Water relations represent a pivotal nexus in plant biology due to the multiplicity of functions affected by water status. Hydraulic properties of plant parts are therefore likely to be relevant to evolutionary trends in many taxa. Bromeliaceae encompass a wealth of morphological, physiological and ecological variations and the geographical and bioclimatic range of the family is also extensive. The diversification of bromeliad lineages is known to be correlated with the origins of a suite of key innovations, many of which relate directly or indirectly to water relations. However, little information is known regarding the role of change in morphoanatomical and hydraulic traits in the evolutionary origins of the classical ecophysiological functional types in Bromeliaceae or how this role relates to the diversification of specific lineages. In this paper, I present a synthesis of the current knowledge on bromeliad water relations and a qualitative model of the evolution of relevant traits in the context of the functional types. I use this model to introduce a manifesto for a new research programme on the integrative biology and evolution of bromeliad water-use strategies. The need for a wide-ranging survey of morphoanatomical and hydraulic traits across Bromeliaceae is stressed, as this would provide extensive insight into structure-function relationships of relevance to the evolutionary history of bromeliads and, more generally, to the evolutionary physiology of flowering plants. [ABSTRACT FROM AUTHOR]

Primary hemiepiphytism was documented in Pleopeltis bradeorum (Polypodiaceae) at the La Selva Biological Station, Heredia, Costa Rica. Multiple sporophytes and gametophytes were observed, photographed, and collected. Gametophytes were found on the trunks of trees and lianas within 2.5 m of the ground. Mature sporophytes with fertile fronds were observed growing ca. 2.5 m above the ground with feeder roots descending to the soil. Additional sterile mature sporophytes were observed ca. 4 m up, on small- and medium-sized branches; though these individuals did not appear to be connected to the ground by roots; that is, they were holoepiphytic. Our findings indicate that P. bradeorum conforms to many of the features characteristic of primary hemiepiphytic ferns. Corresponding to expectation, sporophytes exhibited long-creeping, dorsiventrally flattened rhizomes with dimorphic clasping and feeder roots. The clasping and feeder roots, however, were not strongly differentiated as in other primary hemiepiphytic ferns. Gametophytes departed from expectation by having a cordate thallus. The life history and habit of P. bradeorum documented here indicates that it is both a primary hemiepiphyte and holoepiphyte. [ABSTRACT FROM AUTHOR]

In spite of it is baseline importance for comparative studies with the past and present data, an updated list of marine green algal taxa for the Biosphere Reserve of Sian Ka'an is not yet available. The aim of this paper is to present an updated list of marine green algal taxa for the Sian Ka'an Reserve based on literature and collections made by the authors in 17 localities during 2011-2012. Fifty-five taxa are new records for the study area and thus the list has increased to 129. Additionally five taxa are reported for the first time to Quintana Roo, and 11 to Mexican Atlantic coast. These results contribute to the knowledge of green seaweed diversity and also support the relevance of the Sian Ka'an Reserve as a high priority area for conservation due to their high level of algal biodiversity. [ABSTRACT FROM AUTHOR]

Epiphytism is a major problem world-wide for the Gracilaria mariculture industry that reduces the productivity of commercial farms. Most of the epiphytes associated with Gracilaria chilensis belong to the order Ceramiales. Under laboratory conditions we studied the infection process of Ceramium rubrum rhizoids on G. chilensis collected from a northern Chilean farm. The rhizoid penetration was intercellular. The host cell wall and cortical cells adjacent to the epiphyte appeared compressed and disorganized. The rhizoids presented an extensive dynamic complex endomembrane system, mainly represented by a plentiful endoplasmic reticulum (ER) network, dictyosomes, electron dense material surrounded by ER membranes, membrane bodies and vacuolar sacs with fibrillar material. Two types of cell wall deposition can be suggested: i) one characterized by the direct contact of ER vesicles with the plasmalemma and ii) another represented by the ER contributing material to the cell wall indirectly through vacuolar sacs. This study provides the basis for a better understanding of the infection process involved in the epiphyte-host interaction. [ABSTRACT FROM AUTHOR]

Um estudo taxonômico de Cactaceae epifíticas foi realizado no Estado do Rio Grande do Sul, Brasil. A revisão inclui chaves de identificação, ilustrações, observações ecológicas e taxonômicas, distribuição geográfica e períodos de floração e frutificação das espécies. Foi encontrado um total de seis gêneros e 13 espécies, sendo duas comumente epífitas acidentais, Cereus alacriportanus Pfeiff. e Opuntia monacantha Haw., e 11 epífitas verdadeiras ou habituais, Epiphyllum phyllanthus (L.) Haw., Hatiora rosea (Lagerh.) Barthlott, Lepismium cruciforme (Vell.) Miq., L. houlletianum (Lem.) Barthlott, L. lumbricoides (Lem.) Barthlott, L. warmingianum (K. Schum.) Barthlott, Rhipsalis campos-portoana Loefgr., R. cereuscula Haw., R. floccosa Salm-Dyck ex Pfeiff., R. paradoxa (Salm-Dyck ex Pfeiff.) Salm-Dyck e R. teres (Vell.) Steud. Uma espécie, R. campos-portoana, é referida pela primeira vez para o Estado do Rio Grande do Sul.A taxonomic study of epiphytic Cactaceae in Rio Grande do Sul State, Brazil, was carried out. The survey presents identification keys, illustrations, ecological and taxonomical observations, geographic distribution, and flowering and fruiting periods of the species. A total of six genera and 13 species were found, two being common accidental epiphytes, Cereus alacriportanus Pfeiff. and Opuntia monacantha Haw., and 11 true or selective epiphytes, Epiphyllum phyllanthus (L.) Haw., Hatiora rosea (Lagerh.) Barthlott, Lepismium cruciforme (Vell.) Miq., L. houlletianum (Lem.) Barthlott, L. lumbricoides (Lem.) Barthlott, L. warmingianum (K. Schum.) Barthlott, Rhipsalis campos-portoana Loefgr., R. cereuscula Haw., R. floccosa Salm-Dyck ex Pfeiff., R. paradoxa (Salm-Dyck ex Pfeiff.) Salm-Dyck and R. teres (Vell.) Steud. One species, R. campos-portoana, is referred for the first time for Rio Grande do Sul State.

As espécies analisadas (Cattleya araguaiensis Pabst, C. bicolor Lindl., C. nobilior Rchb. e C. walkeriana Gardn.) apresentam epiderme uniestratificada em ambas as faces da lâmina foliar, ocorrendo estômatos na face abaxial; deposição de cera epicuticular em crostas, escamas, flocos e plaquetas; em C. araguaiensis ocorrem estegmatas incrustados nas células epidérmicas; em todas as espécies ocorre hipoderme com células de paredes espessadas; mesofilo bifacial, compacto; células paliçádicas atípicas, com barras de espessamento; feixes vasculares colaterais dispostos alternadamente, acompanhados por bainha de fibras; cordões fibrosos acompanhados por estegmatas ocorrem longitudinalmente na lâmina foliar; presença de ráfides. Os aspectos descritos revelam acentuada xeromorfia, em função de economia de água.The analyzed species (Cattleya araguaiensis Pabst, C. bicolor Lindl., C. nobilior Rchb. e C. walkeriana Gardn.) present unistratified epidermis at both surfaces with stomata at abaxial surface; deposition of epicuticular wax in crusts, scales, granules and plates; C. araguaiensis presents stegmata at epidermal cells; others characteristics present at all species are: hypodermis cells with thick walls; bifacial and compact mesophyll; atipic cells ofpalisade parenchyma with thichness bars; collateral vascular bundles alternate accompanied by sheath fibers; cordon fibers accompanied by stegmata in the foliar blade; raphids. The described aspects reveal accentuate xeromorphy for water economy.

Studies were carried out to investigate the temporal variation in Sargassum biomass, Hypnea epiphytism and associated fauna. There was a marked variation in the biomass of Sargassum and Hypnea among various sampling periods. Low values for Sargassum were recorded in August and November, while the lower value for Hypnea biomass was recorded in August. An inverse relationship was found between Sargassum biomass and the intensity of Hypnea epiphytism. The density of the total fauna associated to Sargassum showed a marked reduction in May. This variation was influenced by the variation patterns of the dominant faunistic groups (Gastropoda, Gammaridea, Isopoda and Caridea). Significant positive relationships were found between the biomass of Sargassum and Sargassum+Hypnea with the total density of all faunistic groups (per macroalgae biomass unit). However, the influence of Hypnea epiphytism on the phytal organisms was not evidenced.

Litter-trapping plants have specialized growth habits and morphologies that enable them to capture falling leaf litter and other debris, which the plants use for nutrition after the litter has decayed. Litter is trapped via rosettes of leaves, specially modified leaves and/or upward-growing roots (so-called 'root baskets'). Litter-trappers, both epiphytic and terrestrial, are found throughout the tropics, with only a few extra-tropical species, and they have evolved in many plant families. The trapped litter mass is a source of nutrients for litter-trapping plants, as well as food and housing for commensal organisms. Despite their unique mode of life, litter-trapping plants are not well documented, and many questions remain about their distribution, physiology and evolution.-© 2015 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 179, 554-586. [ABSTRACT FROM AUTHOR]

We analyzed the influence of moisture and pH substrate of Araucaria angustifolia (Bertol.) Kuntze e Dicksonia sellowiana Hook. on the richness, composition and community structure of vascular epiphytes within the Araucaria Forest. In order to study the epiphytic community, 20 phorophytes of A. angustifolia and D. sellowiana were selected in one hectare of Araucaria Forest. The phorophytes were divided equally into four intervals of one meter each. Araucaria angustifolia showed 20 species, while D. sellowiana 11. Means of species per host tree were significantly higher in D. sellowiana than for A. angustifolia. The moisture and pH of phorophyte types differ statistically and the most relation was observed between moisture and epiphytic ferns richness. Principal coordinates analysis showed well-defined groupings for phorophyte types and floristic heterogeneity among height intervals. Blechnum acutum (Desv.) Mett. occupied both phorophytes and had the highest importance values, demonstrating high ecological tolerance. The results show that moisture was the factor with the highest influence in the epiphytic community structure, especially for the ferns. [ABSTRACT FROM AUTHOR]

Flora diversity and abundance of epiphytes are specific to their basiphyte species and may relate to variations in the defensive abilities of basiphytes. Thus, investigating the interactions between epiphytes and basiphytes is useful for a better understanding of the biological impact of epiphytism and the survival strategies of basiphytes. We examined the epiphyte density on five sargassacean species at six locations between two study sites, which showed that the epiphytic red alga Neosiphonia harveyi was remarkably less abundant on Sargassum siliquastrum at all locations. To assess its defense mechanism against N. harveyi, we performed bioassays of phlorotannins, which are considered effective in deterring fouling, by culturing sargassacean blades with N. harveyi carpospores and observed the process by which sargassacean blades remove epiphytes. When the carpospores were incubated with various concentrations of dissolved phlorotannins, settlement and germination were inhibited only at the highest concentrations (>0.1 g · L−1), and this effect did not significantly differ among the five sargassacean species. When the carpospores were combined with blades from the five species, many of the spores attached and germinated on every blade. Because N. harveyi penetrated rhizoids into basiphyte tissues, cuticle peeling observed in all five sargassacean species could not remove this epiphyte after germination. However, in S. siliquastrum, the blade tissues around the germlings became swollen and disintegrative, and were removed together with the germlings. The spores normally grew on the dead blades, suggesting that the tissue degradation of S. siliquastrum is triggered by the infection of N. harveyi. [ABSTRACT FROM AUTHOR]