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Fern gametophytes are an often-overlooked part of field studies on ferns due to the challenge of finding material and the difficulty of identifying wild-collected plants. Most existing gametophyte descriptions are derived from lab-reared plants and while it is thought that many of the morphological features are similar under both conditions, we still have a poor understanding of in situ morphology for most taxa. The goal of this work was to document a set of morphological observations from the gametophytes of six different species collected in situ. We discovered identifiable gametophyte populations of Elaphoglossum latifolium, Hymenophyllum myriocarpoum, Lomariopsis maxonii, Polypodium dulce, Polytaenium cajenense, and Sticherus bifidus during the 2022 OTS Tropical Ferns and Lycophytes course in Costa Rica. Gametophytes were collected in the field, observed, and photographed using stereo and compound microscopy. This work represents the first detailed description for these species' gametophytes from field collections and offers insights into their natural morphology. [ABSTRACT FROM AUTHOR]

The coming decades are predicated to bring widespread shifts in local, regional, and global climatic patterns. Currently there is limited understanding of how ferns will respond to these changes and few studies have attempted to model shifts in fern distribution in response to climate change. In this paper, we present a series of these models using the country of New Zealand as our study system. Ferns are notably abundant in New Zealand and play important ecological roles in early succession, canopy biology, and understory dynamics. Here we describe how fern distributions have changed since the Last Glacial Maximum to the present and predict how they will change with anthropogenic climate change – assuming no measures are taken to reduce carbon emissions. To do this, we used MaxEnt species distribution modelling with publicly available data from gbif.org and worldclim.org to predict the past, present, and future distributions of 107 New Zealand fern species. The present study demonstrates that ferns in New Zealand have and will continue to expand their ranges and migrate southward and upslope. Despite the predicted general increased range size as a result of climate change, our models predict that the majority (52%) of many species' current suitable habitats may be climatically unsuitable in 50 years, including the ecologically important group: tree ferns. Additionally, fern communities are predicted to undergo drastic shifts in composition, which may be detrimental to overall ecosystem functioning in New Zealand. [ABSTRACT FROM AUTHOR]

Climate change is expected to increase temperature and temporal precipitation variability leading to higher evapotranspiration and more frequent and severe droughts. While advancements are being made in our understanding of how plants will respond to these changes, gaps remain in our knowledge of species-specific drought response. This is especially true among herbaceous plant communities, including ferns and other seed-free vascular plants. Previous hydraulic work on ferns has almost exclusively concentrated on the leaves, with very little information on the rhizome, which is surprising given that the rhizome is the long-lived perennial organ (making it more costly and important in species survival). Only recently have rhizome hydraulics been explored in the context of drought stress. Similar to observations in many woody trees, fern leaves tend to desiccate and hydraulically disconnect before the perennial stem experiences significant levels of drought-induced embolism, suggesting strong vulnerability segmentation. These findings have significant implications for fern survival during drought. In this review we expand on these observations, integrating information from previous work on plant hydraulics and ecophysiology, to understand the implications of vulnerability segmentation on the response of ferns to future climate change. [ABSTRACT FROM AUTHOR]

We report the case of a phosphaturic mesenchymal tumor of the ankle; an extremely rare lesion that causes osteomalacia via paraneoplastic renal phosphate wasting. A 41-year-old man was referred to plastic surgery with a swelling over the anterior ankle, which had been increasing in size for 1 year. Focused ultrasound assessment was inconclusive, but excision biopsy demonstrated features in keeping with a phosphaturic mesenchymal tumor. Evidence of tumor-induced osteomalacia was subsequently identified on review of historical biochemistry. The patient was followed-up for 1 year with normalization of serum phosphate. In this case report, we present a discussion of the differential diagnosis for foot and ankle soft tissue lesions, and a review of the literature regarding the diagnosis and management of these tumors. Accurate identification of any soft tissue lesion on clinical examination alone is extremely challenging and excision biopsy should be considered in cases of diagnostic uncertainty. [ABSTRACT FROM AUTHOR]

Plants are characterized by their marked plasticity and ability to alter their functional biology to partition ecological niches. However, there are limits to functional trait exploration especially in complex and stressful habitats. Highly specialized traits may control a species ability to explore within and across habitats. Such may be especially true of epiphytes, whose array of unique traits may constrain their ability to cross establish in epiphytic and terrestrial habitats. In the case of ferns, there are few reported examples of species that can grow across these habitats with regularity. However, this study reports and explores species that exhibit great ecological flexibility growing across a wide range of habitats and growth forms. Specifically, we examine species that grow as 1) terrestrially rooted and epiphytic individuals, 2) nest and non-nest-forming epiphytes; and nest-forming terrestrially rooted individuals, and 3) species that grow as terrestrial, epiphytic, and epipetric individuals. We use natural abundance foliar stable isotope ratios (SIR) of N15 and C13, and %N, to explore intraspecific variation in mineral nutrition and water relations across and within niches. Our results reveal the 1) unreported ability of some species to grow across the epiphytic/terrestrial divide, 2) surprising ability of some species to explore these habitats with little to no shift in functional traits; 3) a potentially new function for the nest in nest-forming epiphytes. Finally, our work highlights the need to consider intraspecific trait variation more carefully when studying ferns that occur across a wide range of habitats. [ABSTRACT FROM AUTHOR]