The shortage of reliable primary taxonomic data limits the description of biological taxa and the understanding of biodiversity patterns and processes, complicating biogeographical, ecological, and evolutionary studies. This deficit creates a significant taxonomic impediment to biodiversity research and conservation planning. The taxonomic impediment and the biodiversity crisis are widely recognized, highlighting the urgent need for reliable taxonomic data. Over the past decade, numerous countries worldwide have devoted considerable effort to Target 1 of the Global Strategy for Plant Conservation (GSPC), which called for the preparation of a working list of all known plant species by 2010 and an online world Flora by 2020. Brazil is a megadiverse country, home to more of the world's known plant species than any other country. Despite that, Flora Brasiliensis, concluded in 1906, was the last comprehensive treatment of the Brazilian flora. The lack of accurate estimates of the number of species of algae, fungi, and plants occurring in Brazil contributes to the prevailing taxonomic impediment and delays progress towards the GSPC targets. Over the past 12 years, a legion of taxonomists motivated to meet Target 1 of the GSPC, worked together to gather and integrate knowledge on the algal, plant, and fungal diversity of Brazil. Overall, a team of about 980 taxonomists joined efforts in a highly collaborative project that used cybertaxonomy to prepare an updated Flora of Brazil, showing the power of scientific collaboration to reach ambitious goals. This paper presents an overview of the Brazilian Flora 2020 and provides taxonomic and spatial updates on the algae, fungi, and plants found in one of the world's most biodiverse countries. We further identify collection gaps and summarize future goals that extend beyond 2020. Our results show that Brazil is home to 46,975 native species of algae, fungi, and plants, of which 19,669 are endemic to the country. The data compiled to date suggests that the Atlantic Rainforest might be the most diverse Brazilian domain for all plant groups except gymnosperms, which are most diverse in the Amazon. However, scientific knowledge of Brazilian diversity is still unequally distributed, with the Atlantic Rainforest and the Cerrado being the most intensively sampled and studied biomes in the country. In times of “scientific reductionism”, with botanical and mycological sciences suffering pervasive depreciation in recent decades, the first online Flora of Brazil 2020 significantly enhanced the quality and quantity of taxonomic data available for algae, fungi, and plants from Brazil. This project also made all the information freely available online, providing a firm foundation for future research and for the management, conservation, and sustainable use of the Brazilian funga and flora.
-(Relations between the structure of terrestrial herbaceous synusiae and canopy cover in a seasonal forest in southern Brazil). The terrestrial herbaceous synusiae in tropical and subtropical forests is scarcely studied, mainly concerning its relationship to environmental factors. The aims of this study were to describe the structure of this synusiae in a seasonal forest, in "Parque Estadual do Turvo", in two different seasons and to correlate it to the degree of canopy opening, assessed by hemispherical photographs. Sampling was accomplished in 30 plots of 2 x 2 m. The survey recorded 29 herbaceous species: 13 pteridophytes and 16 magnoliophytes. Lastreopsis effusa (Sw.) Tindale and Thelypteris scabra (C. Presl) Lellinger had the highest frequency and cover. Didymochlena truncatula (Sw.) J. Sm. had high cover and Olyra humilis Nees and Pharus lappulaceus Aubl., high frequency. Mean height was 37 cm (s ± 27). Species diversity (H') and evenness indexes (J') during the summer were 2.771 (nats) and 0.823, respectively. These indexes (P = 0.509), composition and herbaceous cover (P = 0.728) were not significantly different between summer and winter. A correlation was detected between the absolute cover for each plot and the degree of canopy opening (P = 0.005). Compared to other southern Brazilian areas, the high values of diversity, richness, size and cover are consequences of the discontinuous forest canopy, which allows high light incidence on the understory. The non significant variation on the structure of the herbaceous synusiae is indicative of low degree of deciduousness of this forest.Key words -diversity, ecology of herbs, hemispherical photographs, phytosociology, understorey RESUMO -(Relações entre a estrutura da sinúsia herbácea terrícola e a cobertura do dossel em floresta estacional no Sul do Brasil). A sinúsia herbácea terrícola ainda é pouco estudada em florestas tropicais e subtropicais, principalmente no que se refere a sua relação a fatores ambientais. O objetivo deste trabalho foi descrever a estrutura desta sinúsia em floresta estacional, no Parque Estadual do Turvo em duas estações do ano e relacioná-la ao grau de abertura do dossel, medido pelo uso de fotografias hemisféricas. O levantamento de 30 unidades amostrais de 2 x 2 m resultou na amostragem de 29 espécies herbáceas, sendo 13 pteridófitas e 16 magnoliófitas. Lastreopsis effusa (Sw.) Tindale e Thelypteris scabra (C. Presl) Lellinger foram as espécies com maiores freqüências e coberturas. Didymochlena truncatula (Sw.) J. Sm. obteve elevado valor de cobertura e Olyra humilis Nees e Pharus lappulaceus Aubl. alta freqüência. A média das alturas foi de 37 cm (s ± 27). A diversidade (H') estimada no verão foi de 2,771 (nats) e a equabilidade (J') de 0,823, não diferindo significativamente do inverno (P = 0,509), assim como a composição e a cobertura herbácea não diferiram entre as duas estações (P = 0,728). Houve correlação entre a cobertura absoluta por parcela e o grau de abertura do dossel (P = 0,005). As maiores riqueza e diver...
Evolutionary and ecological processes that influenced the assembly of the New World flora are best understood through investigation of spatio-temporal processes of specific lineages, but some groups still lack a historical overview. Here, we produced a well-sampled dated tree, reconstructed ancestral ranges and performed diversification analyses for Sisyrinchium (Iridaceae) to elucidate its evolution in the Americas. Eight molecular markers and samples representing its full geographical range and morphological diversity were used to estimate divergence times with a Bayesian relaxed clock with secondary calibrations. Ancestral range reconstruction under likelihood methods and diversification analyses were performed. Sisyrinchium originated in a broad range including the Andes and Mesoamerica in the Mid-Miocene. Diversification at high elevations occurred in the early diverging lineages, which feature the highest extinction rates. Increase in diversification rate was detected during the Pliocene/Pleistocene after the colonization of lower elevations. Later sympatric speciation in south-eastern Brazil was followed by movements to other regions, including a long-dispersal event to North America. Higher extinction rates were followed by movements to lower elevations, with periods of accelerated Andean orogeny and global temperature decrease. Our results indicate that palaeoclimate and changes in elevational range influenced diversification in Sisyrinchium.
Taxon delimitation and classification remains one of the fundamental bases of evolutionary studies and is especially challenging because processes by which new biological entities arise are complex and non‐linear over time, although continuous. Sisyrinchium (ca. 140 to 216 taxa) is one of the most species‐rich genera of Iridaceae, largely widespread in the Americas. Recent molecular phylogenetic studies have shown that the systematics of the genus is in need of substantial revision. Different data sources were investigated to establish an updated infrageneric classification based on phylogenetic principles. Monophyletic sections of Sisyrinchium were circumscribed using a new phylogenetic framework established from an increased sampling of taxa (107 species), and complementary approaches were combined to provide the most comprehensive infrageneric treatment of the genus proposed so far. Additionally, numerous molecular synapomorphies were identified to reinforce previous taxonomic treatments of tribe Sisyrinchieae (six genera) at the generic level. Major lineages of Sisyrinchium were concordantly resolved with mostly strong to full support by the DNA regions used in the study and ten sections characterized by unique combinations of molecular, morphological and geographical diagnostic characters were recognized. The phylogenetic trees respectively based on plastid + mitochondrial and nuclear ITS DNA regions were generally congruent except for two unplaced species (S. chilense, S. elegantulum) for which ancestral reticulation events were detected. New circumscriptions were provided for seven sections (sect. Cephalanthum, sect. Echthronema, sect. Hydastylus, sect. Segetia, sect. Sisyrinchium, sect. Spathirhachis, sect. Viperella) while three sections (sect. Morphanthus, sect. Rhizilineum, sect. Trichoparcus) were newly described. This work constitutes a robust contribution to elucidate the systematics of Sisyrinchium and emphasizes the need of integrative taxonomic approaches using multiple data sources, not only to improve the delimitation of taxa but also to investigate their evolutionary history.
A remarkable morphological similarity in natural populations of different groups of Sisyrinchium spp. (Iridaceae) makes classification of some species difficult. The present paper focused on two morphological categories of S. sellowianum (MC-I and MC-II) with distinct morphological traits. Morphological, cytogenetic, reproductive biology and genetic studies were performed, aiming to elucidate and better characterize such variation. The basic chromosome number established for the species was x = 9 and diploid and tetraploid populations were observed for MC-I, whereas MC-II showed only diploid populations. Different pollen morphologies were recognized in each morphological category. Based on pollination experiments, MC-I is out-crossing, whereas MC-II is selfing. The populations were highly differentiated (F ST = 0.46, θ B = 0.62). In MC-I, observed variation was greater within populations (69%) than among populations (31%), whereas in MC-II, 61% of the variation was among populations and 39% within populations. This study evidenced that the two morphological categories correspond to distinct and reproductively isolated species and that floral traits reflect their breeding system, with allogamous plants in MC-I and autogamous in MC-II. Furthermore, MC-II is unveiled as S. platycaule, a neglected taxon of Sisyrinchium in Brazil. The tools applied in this study were substantially able to check the identity of the two morphological categories as two different species and present the variation encountered in the taxa.
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