| 1. |
- Molino, S., et al.
(författare)
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First Record of Sporangiasters in the Blechnaceae
- 2021
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Ingår i: American Fern Journal. - : American Fern Society. - 0002-8444. ; 111:3, s. 196-204
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Tidskriftsartikel (refereegranskat)abstract
- Sporangiasters are an uncommon type of paraphyses, occurring in a handful of leptosporangiate fern genera. We report sporangiasters in Parablechnum nesophilum, which is their first recorded occurrence in the Blechnaceae. We provide evidence of their homology to sporangia and discuss their functional significance. The presence of sporangiasters in P. nesophilum is surprising because the species has a well-developed indusium, and paraphyses are generally most common in exindusiate ferns. We surmise that these sporangiasters act as a second stage of protection for the developing sporangia after the indusium retracts. Alternatively, it is possible that sporangiasters may influence the vagility of spores by inhibiting dehiscence and limiting the ability of the annulus to disperse its spores.
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| 2. |
- Ollgaard, B., et al.
(författare)
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The Lycopodiaceae of Panama
- 2021
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Ingår i: Phytotaxa. - : Magnolia Press. - 1179-3155 .- 1179-3163. ; 526:1, s. 1-66
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Tidskriftsartikel (refereegranskat)abstract
- The present paper provides keys to the genera and species of Lycopodiaceae for 6 genera and 40 species recorded from Panama. The treatment includes nomenclature, descriptions of species and information about distribution and habitats, and notes on problems of species delimitation and infraspecific variation. All species are illustrated, and representative specimens are cited.
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| 3. |
- Suissa, J. S., et al.
(författare)
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Mountains, climate and niche heterogeneity explain global patterns of fern diversity
- 2021
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Ingår i: Journal of Biogeography. - : Wiley. - 0305-0270 .- 1365-2699. ; 48:6, s. 1296-1308
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Tidskriftsartikel (refereegranskat)abstract
- Aim It is well known that the distribution of species diversity is spatially heterogeneous, but understanding the factors contributing to this heterogeneity and to the formation of biodiversity hotspots remains a challenge. Here, we seek to improve our understanding of how historical, ecological and evolutionary processes contribute to current patterns of global fern diversity. Location Worldwide. Taxon Ferns. Methods To evaluate the drivers of global fern diversity, we integrate over 800,000 georeferenced species occurrence records of nearly 8000 species, a time-calibrated phylogeny and seven climate and environmental layers. We use these data to summarize diversity and evolutionary patterns at a resolution of 100 x 100 km, and identify hotspots of fern species richness and endemism. We compare these hotspots to neighbouring non-hotspot regions to provide insight into the factors controlling global patterns of fern diversity. Results Tropical and subtropical mountains harbour a disproportionate amount of species relative to the land area they occupy; 58% of global species richness occur in eight principally montane hotspots together comprising just 7% of Earth's land area. We identify hotspots of fern species richness and endemism that are universally characterized by disproportionately high ecological variation. We demonstrate that total fern species richness scales linearly with available climate space at regional and global scales. Main Conclusions Areas of high environmental heterogeneity harbour a disproportionate amount of fern species, and global patterns of extant fern diversity reflect the distribution of these areas, especially in mountains at lower latitudes. Persistence of ancient lineages in areas with long-term climatic stability helps explain exceptional endemism in regions such as Malesia.
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