Phenological studies for Cuban bulrush [Oxycaryum cubense (Poepp. & Kunth) Lye] have been limited to the monocephalous form in Lake Columbus (Mississippi). Accordingly, there is little available information on potential phenological differences among O. cubense forms (monocephalous vs. polycephalous) and populations in other geographic locations in the United States. Therefore, seasonal patterns of biomass and starch allocation in O. cubense were quantified from two populations in Lake Columbus on the Tennessee-Tombigbee Waterway in Mississippi (monocephalous), two populations from Lake Martin in Louisiana (polycephalous), and two populations from Orange Lake in Florida (polycephalous). Monthly samples of O. cubense inflorescence, emergent, and submersed tissue were harvested from two plots per state from October 2021 to September 2022. During monthly data collection, air temperature and photoperiod were recorded. Starch allocation patterns were similar among all sites, with starch storage being less than 1.5% dry weight for all plant tissues. Biomass was greatest in Lake Columbus (monocephalous; 600.7 g dry weight [DW] m−2) followed by Lake Martin (polycephalous; 392.3 g DW m−2) and Orange Lake (polycephalous; 233.85 g DW m−2). Peak inflorescence biomass occurred in the winter for the Lake Martin and Orange Lake populations and in the summer for the Lake Columbus population. Inflorescence biomass in Lake Columbus had a positive relationship (r2 = 0.53) with warmer air temperatures. Emergent and submersed biomass generally had negative relationships with both photoperiod and temperature (r2 = 0.02 to 0.77) in all sites. Peak biomass was also negatively related to temperature and photoperiod. Results from this study indicate that there are differences in biomass allocation between the two growth forms of O. cubense and that growth can occur at temperatures below freezing. Low temperature tolerance may allow this species to expand its range farther north than previously suspected.

Bunodeopsis pelagica is one of the few species of sea anemones known to be found in the floating algae of Sargassum spp. It has been reported in the North Atlantic, particularly in the Canary Islands and the coast of Jamaica. The present study is the first to report the occurrence of B. pelagica in the Mexican Atlantic, found as epiphyte on Sargassum natans off Alacranes reef (southern Gulf of Mexico) and in Puerto Morelos reef (Mexican Caribbean), revealing that this species is much more widespread than has been reported. Bunodeopsis pelagica is mainly distinguished from other species of Bunodeopsis by having simple minute protuberances on its column, while its congeners have larger and much more developed vesicular projections. With the record of B. pelagica, the number of known species of actiniarian sea anemones from the Mexican Atlantic increases to 23.

Tropical forest ecosystems are rich in epiphytes that make up a significant portion of the overall plant diversity. However, epiphytic plants are often understudied due to inaccessibility and the lack of basic ecological information poses challenges to their conservation, particularly in a time of rapid global change. The mule-ear orchid, Trichocentrum undulatum (Orchidaceae), is a large flowering epiphyte found in southern Florida (USA), the Greater, and Lesser Antilles including Cuba. The plant is Florida state-listed as endangered with only one remaining small and declining population in a coastal mangrove forest due to historical extraction and habitat destruction. Currently, there is no systematic understanding of the species’ habitat requirements. To fill this void, we compared the habitat and microhabitat of the species on its northern distribution edge (southern Florida) and the core range (in Cuba). The Florida population has only one host species, Conocarpus erectus, found in one habitat type. This is in sharp contrast to the 92 documented hosts and 5 habitats across 8 provinces in Cuba. Based on our findings from Cuba, we suggest conservation and restoration options in Florida by proposing potential suitable host plants and habitats. Proactive restoration of this species will help to ease the threat from sea-level rise to the species by securing and expanding range margins.

Common gardens are experimental plantations for comparing the performance of tree species while eliminating many of the variables that prevail in natural tree stands. The aim of this study was to evaluate the biodiversity of corticolous lichens on Danish tree species (Acer pseudoplatanus, Alnus glutinosa, Betula pendula, Fagus sylvatica, Fraxinus excelsior, Quercus robur and Tilia cordata) under common garden conditions and to examine the height distribution of particular lichen species. Observations were recorded through regular sampling of at least 36 lichen species on the main stems (from the base of the stem to the treetops) of 44-year-old trees at four common garden sites. Acer pseudoplatanus and Fraxinus excelsior had the greatest lichen species richness and Shannon diversity values while these measures were significantly lower for Betula pendula and Fagus sylvatica. The distribution of lichen species appeared biased among tree species. The general lichen distribution and relative sample height were weakly related (nonmetric multidimensional scaling). However, single lichen species showed a clear differential distribution along the tree stem (P < 0.001, non-parametric multiplicative regression and logistic log-binomial regression). Lepraria incana, Pseudosagedia aenea and Arthonia atra were mainly found at the stem base while Lecanora carpinea, L. chlarotera, Lecidella elaeochroma, Physcia tenella and Xanthoria parietina, were most abundant at around 70% of the total tree height. The differential distribution of single lichen species presumably reflects different specific requirements during spore germination and thallus growth. By isolating the unique effect of key variables (tree species and height), this study contributes to the knowledge base of corticolous lichen ecology.

Systematic data collection for direct statistical analysis of biodiversity trends tends to be focused on charismatic fauna and flora such as birds or vascular plants. When subsequently applied by conservation agencies in summary metrics tracking habitat and species protection, these patterns in biodiversity loss or gain can fail to capture outcomes for groups that have a prominent importance in habitat composition, diversity and ecological function, such as algae, bryophytes, lichens and other fungi. Such species are primarily recorded on an ad hoc basis by taxonomic specialists, yielding noisy data that present problems in robustly identifying trends. This study explored the use of ad hoc field-recorded data as a potential source of biodiversity information, by comparing the pattern of recording for carefully selected indicator species with those for benchmark or control species as a proxy for recording effort. Focusing on Scotland’s internationally important epiphytic lichens, and especially ‘old-growth’ indicator species, British Lichen Society data revealed a decline in the extent of these species in Scotland, relative to recording effort, over a period of five decades. A recent slowing in the rate of decline is observed but remains to be confirmed. The long-term decline is consistent with the effect of land use intensification, resulting in small and isolated populations that are vulnerable to extinction debt. We caution that remedial protection and monitoring for such populations remains vital as a complement to Scotland’s larger scale ambition for increased woodland extent and connectivity.

Tropical montane cloud forests (TMCF) are characterized by short trees, often twisted with multiple stems, with many stems per ground area, a large stem diameter to height ratio, and small, often thick leaves. These forests exhibit high root to shoot ratio, with a moderate leaf area index, low above-ground production, low leaf nutrient concentrations and often with luxuriant epiphytic growth. These traits of TMCF are caused by climatic conditions not geological substrate, and are particularly associated with frequent or persistent fog and low cloud. There are several reasons why fog might result in these features. Firstly, the fog and clouds reduce the amount of light received per unit area of ground and as closed-canopy forests absorb most of the light that reaches them the reduction in the total amount of light reduces growth. Secondly, the rate of photosynthesis per leaf area declines in comparison with that in the lowlands, which leads to less carbon fixation. Nitrogen supply limits growth in several of the few TMCFs where it has been investigated experimentally. High root : shoot biomass and production ratios are common in TMCF, and soils are often wet which may contribute to N limitation. Further study is needed to clarify the causes of several key features of TMCF ecosystems including high tree diameter : height ratio.

The vertical gradient of the community structure of epiphytic lichens in forest canopies was studied in southern Estonian coniferous forests. All lichen species on 15 Norway spruces and 15 Scots pines were recorded; age of trees ≥100 years. Species were sampled in height ranges on entire trees from the bottom to the top. The number of lichen species on pine trunks decreased with height from the ground, whereas the number of species on branches increased. There was no significant vertical change in the number of lichen species on spruce trunks; number of species on spruce branches was highest in mid canopy. The mean number of lichen species on a tree was 41 in spruces and 34 in pines; the mean number of species on the first 2 m was 14 in spruces and 12 in pines. According to the results, about two thirds of a tree's lichen species remain unrecorded if only the first 2 m near the ground are surveyed. Many lichen species were found only higher than 2 m, including several common species (e.g. Buellia griseovirens, Lecanora pulicaris, and Melanohalea exasperatula), but also some locally rather rare (Fellhanera subtilis, Micarea nitschkeana, Rinodina efflorescens) or red-listed ones (Evernia mesomorpha, Usnea barbata, U. fulvoreagens, U. substerilis, U. wasmuthii) and one new species for Estonia, Lecanora farinaria. There were also some species, such as Chaenotheca stemonea, Cladonia cenotea and C. norvegica, that were restricted to the lowest 2 m. The results indicate that canopy lichens form a significant part of lichen diversity in coniferous forests, and could add valuable information when estimating forest lichen diversity for conservation and other purposes.

Low germination and seedling survival probabilities are reported in various species of epiphytic bromeliad (Benzing 1978, Hietz et al. 2011, Toledo-Aceves & Wolf 2008, Winkler et al. 2005; but see Cascante-Marín et al. 2008). If germination and seedling survival are limiting factors in the life cycle, differential germination and seedling survival between species should be reflected in the relative abundance of established plants (Cascante-Marín et al. 2006, 2008) and in their presence or absence in secondary vegetation (Hietz et al. 2011), while differential germination within the tree would be expected to contribute to a heterogeneous distribution of established plants within the canopy (Hietz et al. 2011, Zotz & Vollrath 2002). Many factors influence the performance and distribution of epiphytes, including forest condition, disturbance type, distance from seed source, tree size and species, microclimate, epiphyte population dynamics and physiology (Cascante-Marín et al. 2009, Hietz et al. 2011, Valencia-Diaz et al. 2010, Zotz & Hietz 2001). In this study, we tested whether germination and seedling survival rates differ between the epiphytic bromeliads Tillandsia multicaulis Steud., T. punctulata Schldl. & Cham. and T. butzii Mez, and whether species abundance reflects the ability to germinate and survive as seedlings within the cloud-forest canopy. We also explore how morphological and physiological traits of the studied species can influence their early establishment.

Biotechnological techniques comprise useful tools for the conservation of endangered plant genetic resources. In the present work, polymorphism and usefulness of amplified fragment length polymorphism (AFLP) markers in assessing the genetic diversity in populations of Billbergia zebrina were investigated in nodular cultures and adult plants of the species. AFLP markers revealed moderate-to-high genetic diversity based on the estimations of Nei's gene diversity (mean He = 0.28), Shannon index of diversity (mean HS = 0.48) and the number of polymorphic fragments (mean of 56.17 polymorphic fragments over six primer pairs). In comparison to published studies of population genetics performed in other bromeliad species, the present study suggests that natural populations of B. zebrina likely maintain high levels of genetic diversity, an important feature towards conservation of plant genetic resources. The results obtained reveal that AFLP markers comprise a powerful tool in order to assess the levels of genetic diversity in natural populations of this endangered species. Integrating AFLP markers with in vitro propagation techniques is understood as an adequate strategy for conservation programmes of this species.

The distribution of epiphytes differs between branches within tree crowns as well as within habitats. Where the original forests have been lost, shade coffee plantations can be important refuges for epiphytes, but are not suitable for all species. To understand what affects habitat quality, we transplanted 1440 seedlings each of two orchids, one, Lycaste aromatica, restricted to forests, the other, Jacquiniella teretifolia, common on trees in coffee plantations and in forests. Seedling mortality and growth were compared between three forests, three young and three old coffee plantations to test for differences between habitats and to analyse which habitat features affect growth and mortality. In J. teretifolia there was no clear pattern of habitat effect on mortality (c. 0.08 mo−1), but the production of new shoots was higher in coffee plantations than in forests. In L. aromatica, growth rates as well as seedling mortality increased over time. During the last census growth rates in forests (1.8 mm mo−1) were significantly higher than in old (0.9 mm mo−1) and young (1.2 mm mo−1) coffee plantations, and seedling mortality was about four times higher in old (0.10 mo−1) and young (0.11 mo−1) coffee plantations than in forests (0.025 mo−1), which may explain the natural absence of L. aromatica from coffee plantations. Mortality in L. aromatica at individual sites was negatively correlated with bryophyte cover on branches (Pearson r = –0.75) and positively with lichen cover (r = 0.70) and canopy openness (r = 0.75). Branch cover with non-vascular epiphytes, whether directly responsible by improving the water supply to epiphytes or indicative of differences in microclimate, may be a useful indicator of suitable habitats for vascular epiphytes.

In the tropical forest of Barro Colorado Island, habitat characteristics, diel acidity changes, CO2 uptake and growth were investigated for the epiphytic cactus Epiphyllum phyllanthus (L.) Haw. It occurred most frequently in tree cavities with its roots in canopy soil and was especially abundant on two tree species: Platypodium elegans J. Vogel and Tabebuia guayacan (Seem.) Hemsl. Its maximum net CO2 uptake rates were low under natural conditions (1.4 μmol m−1) but were comparable to those of other CAM and C3 epiphytes under wet conditions in a screenhouse. Under both natural conditions and in the screenhouse, partial shade enhanced growth and CAM activity. When plants grew under a photosynthetic photon flux of c. 4 mol m−2 d−1, their nocturnal acidity increase and total net CO2 uptake were twice as much as for plants growing at lower (an average of 2.4 mol m−2 d−1) and higher (7.7 mol m−2 d−1) photosynthetic photon fluxes. Stem elongation was 27% greater at the intermediate photosynthetic photon flux. Seedlings of E. phyllanthus survived three months of drought and responded rapidly to rewetting, recovering fully within three days. Transpiration rates and nocturnal acidity increases also recovered to the values of well-watered plants a few days after rewetting, indicating that this species can take advantage of episodic rainfall during the dry season.

Orchid diversity, distribution and host specificity were examined in a tropical watershed in the Luquillo Experimental Forest of Puerto Rico. Eleven orchid species occur in the area. The low diversity is attributed to island isolation and large-scale hurricane disturbances. Pleurothallis ruscifolia and Maxillaria coccinea were by far the most abundant species in the area and occurred on the largest number of host species and host zones. None of the orchids were host specific or host zone specialists although preferences for hosts and vertical host zones were encountered.

Only 8.2% of the 426 trees and shrubs and 24.4% of the 45 species surveyed were orchid phorophytes (= hosts). Examination of host distribution by diameter at breast height (DBH) showed that 80.5% were greater than 16 cm DBH. Orchid species in the area tend to occur on rough bark hosts, but their preferences are not statistically significant. Guarea guidonia (Meliaceae) and Dacryodes excelsa (Burseraceae) are the two most important orchid hosts in our study site comprising 62.9% of all host trees. Careful management of these two tree species is suggested, since these species may be crucial to the maintenance of orchid abundance and diversity in the area.

We studied the interaction between the bromeliad Werauhia gladioliflora and its flower visitors in the Caribbean lowland forest of Costa Rica, in order to quantify the mutual benefits to both partners. Over 6 y, the bromeliads flowered mainly between October and December; with an individual inflorescence flowering for an average of 34 d (n = 233 inflorescences). The bromeliad showed a flexible breeding system with autogamy occurring in addition to cross-pollination. Exclusive pollinators were small nectar-feeding bats (Phyllostomidae: Glossophaginae). The average volume of nectar produced per flower was 1.1 ml (n = 25 flowers). The main visitor was the bat Glossophaga commissarisi, which approached the flowers exclusively using hovering flight. Visitation by bats, measured by infrared light sensors, occurred throughout the night with an activity peak after midnight. Median hovering duration of the bats at the flowers was 320 ms (n = 1246 visits). Hourly mean of hovering duration was negatively correlated with hourly nectar secretion rate. The flower visitation behaviour of a bat over the night seems to be shaped by a combination of intrinsic physiological factors and by nectar availability. Size of both flowers and visitors make Werauhia gladioliflora a very accessible system for quantification of factors affecting evolution of bat–plant interactions.

Native orchid cultivation is a compatible alternative for impoverished coffee farmers in southeastern Mexico who are in crisis due to falling prices. Sustainable orchid cultivation is also an urgent necessity as an alternative to nonsustainable extraction from protected reserves, forest fragments and traditional coffee plantations, and to restore and conserve populations within these habitats. Our objective was to test the effects of locally available substrates and fertilizers upon orchids cultivated under typical rural conditions in coffee-producing areas in Soconusco, Chiapas. Seven species of epiphytic orchids native to Soconusco region—Cattleya aurantiaca, Brassavola nodosa, Prosthechea (Encyclia) chacaoensis, Anathallis (Pleurothallis) racemiflora, Cattleya skinneri, Cycnoches ventricosum and Encyclia cordigera—were propagated in vitro, acclimatized and established in rustic orchid galleries in the home gardens and plantations of coffee growers. Locally available waste products were used as substrates: clay tiles, tree bark, bamboo, seed hulls of pataxte (Theobroma bicolor) and wire baskets filled with bark chips. Two cheap and readily available commercial foliar feeds, Algaenzims (an organic product) and Bayfolan (a synthetic product) were tested. First, the substrates alone were tested for a period of 6 months to 1 year, then a combination of substrates and fertilizers were tested for 6 months, for effects upon leaf and root growth and root number. The mortality rates of these nonsymbiotically propagated, epiphytic orchids during the acclimatization phase, prior to these experiments, were high, between 60 and 90%. Once established in rustic galleries, the young orchid plants showed no preference for a particular substrate, survival depended upon technical problems during establishment, relating to difficulties with the attachment of plants to substrates, and the variable quality of care and attention offered by the farmers. Both fertilizers significantly improved one or all the parameters studied, and possibly counteracted the negative effects of the absence of symbiotic fungi, which, under natural conditions, are essential for orchid seed germination and adequate development of the young plant. More than half of the producers did not continue with the orchid cultures for economic and cultural reasons.

We studied oribatid (Acari: Oribatida) communities in two distinct microhabitats (litter and root) of the bird's nest fern (Asplenium nidus) in an approximately 4-ha area in a subtropical forest, Okinawa, Japan. We collected a total of 15 729 oribatid mites from 37 ferns and examined whether the size and height of the ferns and the distance between ferns affected the structure of the oribatid communities in terms of the species composition, number of individuals, density (individuals per 100 g dry wt of substrate), number of species and species diversity (Simpson's index). Oribatid communities differed significantly in species composition and density between litter and root components and were evenly distributed horizontally throughout the plot. The density of oribatid mites in the litter decreased significantly with increasing height of the ferns, and the species composition and the numbers of individuals and species in the litter were affected by fern size. Our results suggest that the litter and root of bird's nest ferns allowed diverse oribatid communities to become established, and variations in size and height of the ferns may help to maintain or enhance the diversity of oribatid communities in bird's nest ferns in subtropical forests.

The aims of this study were to investigate the roosting ecology and social organization of the spotted-winged fruit bat, Balionycteris maculata (Megachiroptera), within an old-growth Malaysian dipterocarp forest, and test the hypothesis that males spend a significantly greater proportion of the night in the immediate vicinity of their day roosts than females. Balionycteris maculata roosted in cavities and formed small harem groups that consisted of one adult male accompanied by up to nine adult females and their dependent young. Both male and female bats foraged locally, within approximately 1 km of their roost sites. However, in contrast to females, which remained away from the roost site throughout the night, both harem and solitary adult males divided their nightly activity between foraging and returning to their roost sites. Individual females were also found roosting sequentially with up to three different males. Hence, these results suggest that B. maculata has a resource-defence polygynous mating system, in which the roost cavity may represent a critical and defendable resource by which males recruit and gain improved reproductive access to females. Roost cavities occupied by B. maculata were found within a number of different forest structures, including ant nests, termite nests and the root masses of epiphytes. The consistent shape and position of the cavities, along with a single observation of cavity enlargement, provide the first evidence of roost-cavity excavation, by a megachiropteran bat, within the nests of social insects. Although the cues by which females select their roost sites are unclear, some aspect of roost cavity size, or condition, may provide a possible means by which females can assess the reproducÍtive fitness of potential mates.

The first known indicator of probable fern epiphytism in the Tertiary fossil record is documented from the Eocene London Clay of southeast England. This pyritised fern rachis exhibits major deviation from the basic form of petiolar vascular trace morphology shown by the other London Clay fossil ferns and is here attributed to the Polypodiaceae. This represents the first known occurrence of this family in the London Clay macroflora, and brings the total of distinct fern rachis types from the Lower Tertiary of southeast England to six. The significance of this find is interpreted in relation to its probable origins from a tropical rainforest palaeoflora in which it is proposed that this specimen represents the first occurrence of an epiphytic component.

Amomum roseisquamosum (Zingiberaceae) is described from Sarawak, Borneo. This new species is related to A. borneense and A. epiphyticum of Smith's (1989) Group V for Bornean species, sharing an epiphytic habit, crested anther-thecae and flattened fruits, but differs in having white flowers, a shorter corolla tube equal to the calyx tube, and lateral petals connate to the labellum. The systematic position is discussed.