Resumo No final da década de 1960, pesquisadores do Museu Paraense Emílio Goeldi (MPEG) iniciaram as coletas botânicas na Serra dos Carajás, resultando em um expressivo acervo e interessantes descobertas sobre a flora local, marcada por endemismos e pressão por atividades mineradoras. Em 2014, foi estabelecido o projeto "Flora das cangas da Serra dos Carajás" através da cooperação entre o MPEG e o Instituto Tecnológico Vale de Desenvolvimento Sustentável (ITVDS), visando especialmente a elaboração da flora das cangas da FLONA Carajás. Um acervo de cerca de quinze mil exsicatas, depositadas principalmente nos herbários MG e BHCB além de HCJS, INPA, IAN, NY e RB constitui a base para o desenvolvimento da flora. Até o momento, a flora inclui 151 famílias de angiospermas, gimnospermas, licófitas e samambaias e briófitas (musgos e hepáticas). Neste trabalho apresentamos um breve histórico dos estudos botânicos na região, caracterização da área de estudo, e procedimentos metodológicos adotados no desenvolvimento do projeto. Também, constitui a introdução para o volume 1 da Flora das cangas de Carajás composto por 55 famílias, sendo quatro de briófitas, duas de licófitas, oito de samambaias, uma de gimnospermas e 40 de angiospermas, incluindo 139 gêneros e 248 espécies.
This compilation of ferns and lycophytes in Brazil is an update of the one published in 2010 in Catálogo de Plantas e Fungos do Brasil. The methodology consisted in collecting data from regional checklists, taxonomic revisions, and selected databases. Invited specialists improved the list accessing a website housed at the Jardim Botânico do Rio de Janeiro. The results show 1,253 species: 1,111 of ferns and 142 of lycophytes. This number is 6.5% higher than the previous one (1,176 spp.). The percentage of endemic species decreased from 38.2% to 36.7%. We recognized 36 families and 133 genera (vs. 33 families, 121 genera in 2010). The 10 most diverse families are Pteridaceae (196 spp.), Dryopteridaceae (179), Polypodiaceae (164), Hymenophyllaceae (90), Thelypteridaceae (86), Aspleniaceae (78), Lycopodiaceae (64), Selaginellaceae (55), Anemiaceae (51), and Cyatheaceae (45). The three most diverse genera are still Elaphoglossum (87 spp.), Thelypteris (85), and Asplenium (74). The richest phytogeographic domain continues to be in the Atlantic Rainforest with 883 species which also has the largest number of endemic and threatened species, followed by the Amazon Rainforest (503), Cerrado (269), Pantanal (30), Caatinga (26), and Pampa (eight). Minas Gerais remains as the richest state (657 spp. vs. 580 in 2010).
The fern family Blechnaceae, with about 250 species, has traditionally comprised one large genus, Blechnum, plus seven to nine smaller genera, most with fewer than 10 species. Several phylogenetic analyses strongly suggest that Blechnum in the traditional sense is not a monophyletic group. We propose a new classification for the family, with three subfamilies and 24 genera. All genera are described and new combinations are provided, with an estimate of species number for each genus. We also provide a key for the identification of the genera.
Knowledge of the geographic distribution of plants is essential to underpin the understanding of global biodiversity patterns. Vascular epiphytes are important components of diversity and functionality of Neotropical forests but, unlike their terrestrial counterparts, they are under-represented in large-scale diversity and biogeographic analyses. This is the case for the Atlantic Forest - one of the most diverse and threatened biomes worldwide. We provide the first comprehensive species list of Atlantic Forest vascular epiphytes; their endemism patterns and threatened species occurrence have also been analyzed. A list with 2,256 species of (hemi-)epiphytes - distributed in 240 genera and 33 families - is presented based on the updated Brazilian Flora Checklist. This represents more than 15% of the total vascular plant richness in the Atlantic Forest. Moreover, 256 species are included on the Brazilian Red List. More than 93% of the overall richness is concentrated in ten families, with 73% represented by Orchidaceae and Bromeliaceae species alone. A total of 78% of epiphytic species are endemic to the Atlantic Forest, in contrast to overall vascular plant endemism in this biome estimated at 57%. Among the non-endemics, 13% of epiphytic species also occur either in the Amazon or in the Cerrado - the other two largest biomes of Brazil – and only 8% are found in two or more Brazilian biomes. This pattern of endemism, in addition to available dated phylogenies of some genera, indicate the dominance of recent radiations of epiphytic groups in the Atlantic Forest, showing that the majority of divergences dating from the Pliocene onwards are similar to those that were recently reported for other Neotropical plants.
Isoetes serracarajensis and I. cangae, two new species from northern Brazil, are described, illustrated, and compared to similar species. Isoetes serracarajensis can be distinguished from other species by a set of characters including triangular to linear microphylls, a reniform-orbicular labium, a rudimentary velum covering up to 1/5 of the sporangial surface, dark brown to red-brown sporangia and verrucate megaspores (verrucae type 1). Isoetes cangae presents large microphylls, a reniform-orbicular labium, a rudimentary velum covering only up to 1/4 of the sporangium surface, hyaline sporangia and verrucate (verrucae type 2) to tuberculate megaspores (tubercles type 3). Based on the IUCN criteria, we suggest that Isoetes serracarajensis should be classified as vulnerable (VU) and Isoetes cangae included as critically endangered (CR).