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Focuses on bromeliads, a family of flowers indigenous to the Mata Atlantica of the Amazon river basin. Diversity of the family Bromeliaceae; Number of species believed to be endangered, vulnerable or extinct; Need for researchers to learn more about the reproductive methods of bromeliads to prevent further extinction.

We present the rediscovery of Banisteriopsis magdalenensis, including an updated morphological description, illustrations, distribution map, and notes on conservation, ecology and taxonomic affinities. The species is endangered and appears to be confined to rocky outcrops in the Atlantic Forest of Northern state of Rio de Janeiro, Brazil, where two populations were found growing apart within the limits of Desengano State Park.

The Guayana Shield is one of the oldest geological formations in South America, ranging from southern Colombia, Venezuela, and the Guianas to the extreme north of the Brazilian states of Amazonas and Roraima. Because of its ancient origin and isolation from other mountain ranges in South America, it harbors a rich flora with high levels of endemism. Recent expeditions to remote areas in the Brazilian portion of the Guayana Shield generated many new herbarium collections. Through these efforts, we report the first records for Brazil of 57 species and infraspecific taxa of vascular plants. In most cases, the taxa are narrowly distributed and were previously known from nearby populations in other countries. In other cases, however, the new Brazilian records expand considerably the known geographical distributions of the taxa. O Escudo das Guianas é uma das formações geológicas mais antigas da América do Sul, que vai desde sul da Colômbia, Venezuela e as Guianas ao extremo norte dos estados brasileiros do Amazonas e Roraima. Devido a sua origem antiga e isolada de outras cadeias de montanhas da América do Sul, abriga uma rica flora com altos níveis de endemismo. Expedições recentes para áreas remotas na porção brasileira do Escudo das Guianas geraram novas coleções de herbário. Através destes esforços, relatamos os primeiros registros para o Brasil de 57 espécies e táxons infraespecíficos de plantas vasculares. Na maioria dos casos, os táxons eram previamente conhecidos a partir de populações próximas em países vizinhos. Em outros casos, porém, os novos registros brasileiros expandem consideravelmente as distribuições geográficas conhecidas dos táxons.

Inselbergs occur as mostly dome‐shaped rock outcrops in all climatic and vegetational zones of the tropics. Consisting of Precambrian granites and gneisses, they form ancient and stable landscape elements. Due to harsh edaphic and microclimatic conditions, the vegetation of inselbergs differs markedly from those of the surroundings. Monocotyledonous mats form one of the most characteristic communities of this ecosystem. The floristic composition of this community was studied on six inselbergs located in the Brazilian Atlantic rainforest. Dominating are Bromeliaceae (Alcantarea, Encholirium), Velloziaceae (Vellozia), Cactaceae (Coleocephalocereus) and the Cyperaceae Trilepis. The alpha diversity of the mats was relatively uniform among the six outcrops. However, beta diversity varied considerably between the different sites. Beta diversity was highest at the most speciose locality indicating a high degree of stochasticity in colonization. In contrast to the low diversity mats on West African inselbergs, the Brazilian rock outcrops bear a floristically more diverse mat community rich in endemics. Thus the edaphically controlled inselberg vegetation reflects the outstanding diversity of the Mata Atlaântica. Possibly the high species richness of mats on East Brazilian inselbergs is a consequence of a large species‐pool. The processes that regulate regional and local diversity in the Mata Atlaântica are not fully clear. It is assumed that historical (i.e. long‐term stability) and biotic (i.e. evolutionary interchange of taxa between canopies and rock outcrops followed by differentiation of local populations) conditions have promoted high rates of speciation and their coexistence in isolated habitats. A danger to the unique vegetation of East Brazilian inselbergs is the establishment of invasive weeds.