Pedro Lage Viana

Summary: A new species of Guadua (Poaceae, Bambusoideae) from the Amazon Basin is described and illustrated. Guadua londonoae is easily distinguished from other species in the genus by a unique combination of primarily vegetative morphological characters. The most prominent diagnostic feature is the size of the auricles on the foliage leaves, which are on average four times longer than the maximum length previously recorded for any Guadua species. This species occurs in the southern and central Amazon rainforest, distributed mainly along the Madeira and Tapajós River Basins, where it grows along forest edges and in gallery forests. A morphological description, illustrations, field photographs and a distribution map are provided.

A new species of Roucheria (Linaceae) was revealed through a vegetation monitoring campaign in a long-term permanent plot in Santa Teresa municipality, Espírito Santo state, southeastern Brazil. Here, we describe and illustrate Roucheria krenakiana, a canopy tree of the montane Atlantic Forest, which stands out for its obovate leaves with obtuse apex, crenulate margins and flowers with pale green petals and 3 to 5 styles, as well as congested axillary cymules, caducous stipules, and a glabrous ovary with 3–5 locules. We provide its description, illustration, phenology, a preliminary conservation assessment, and a discussion of its morphological relationships with closely related species. Our study highlights that long-term forest monitoring, when integrated with systematic voucher collecting, strengthens the documentation of poorly known lineages, and can reveal undescribed species.

The biodiversity crisis, driven by accelerated habitat conversion, climate change, and other human-induced threats, significantly increases the need for comprehensive taxonomic research aiming for effective conservation strategies. Species conservation initiatives have faced challenges recently, especially in hyperdiverse regions, due to insufficient surveys and misidentification, highlighting the crucial role of taxonomy to address these issues. Lamiaceae, includes about 8,100 species, many with significant economic importance. However, certain lineages within it, such as the South American genus Glechon, remain understudied. Glechon comprises seven species and is primarily distributed in southern Brazil, Argentina, Paraguay, and Uruguay. This study focuses on Glechon hoehneana, a rare and understudied species, endemic to the Brazilian Atlantic Forest. We conducted extensive herbarium and field work and report new localities for G. hoehneana, within the Mantiqueira mountain range, extending the known distribution further north, into Minas Gerais state. A detailed taxonomic description is provided, accompanied by a key to Brazilian species of Glechon, as well as an updated distribution map, and an IUCN conservation status assessment, highlighting its main threats. A clarification on the typification of the genus and its type species is also presented. We call for the increase of botanical inventories and protection of narrow endemic species, particularly in biodiversity-rich but under-protected regions.

A taxonomic revision of Brazilian Notylia is presented. Among the 33 binomials evaluated, 14 are recognized as species, with only two endemic to the country. Notylia tenuis is re-established at species level, and N. fragrans is confirmed as an accepted name. Descriptions, identification key, photographic plates, illustrations, distributions, taxonomic notes and conservation status (for just the endemic species) are presented. Additionally, a lectotype is designated for N. microchila.

The Cerrado is a diverse biome with a mosaic landscape that includes grasslands, savannas, and forests. Gallery forests are crucial for biodiversity and water resource maintenance. Bamboos are common in these ecosystems and due to their rapid growth, they facilitate the regeneration of tree species. Given their importance and the challenges in species identification, this study aims to catalog the native bamboo flora (Poaceae: Bambusoideae) of the Distrito Federal (DF). Identification keys, morphological descriptions, taxonomic comments, illustrations, conservation status assessments, and distribution maps were developed. Expeditions were conducted between September 2018 and February 2020 to collect specimens, alongside literature reviews and herbarium analyses. We identified 10 genera and 16 species of Bambusoideae. Olyra had the highest species richness, with five species, followed by Aulonemia and Guadua, each with two. The genus Chusquea was first recorded in the Central-West region of Brazil. We also found new populations of Aulonemia xerophylla, a threatened species. Some previously recorded species were not located, suggesting possible local extinction. This study enhances knowledge of bamboo diversity and conservation in the Cerrado, providing valuable information for future research and environmental management.

Trichanthecium is a genus of panicoid grasses that occurs in tropical and subtropical areas of the Americas, continental Africa and Madagascar, comprising 52 species. Revisions of herbaria materials revealed the need for new typifications of names associated with Trichanthecium to stabilize the nomenclature of the genus. In this article, we designate lectotypes for 16 names (three in Isachne and 13 in Panicum) within ten species of Trichanthecium: Panicum cyanescens var. rigidiusculum (Trichanthecium cyanescens), P. dinklagei (T. dinklagei), P. pusillum var. glabriglumatum (T. glaucocladum), P. homblei (T. margaritiferum), Isachne kidumaensis, I. wombaliensis and P. fulgens (T. nervatum), P. perpusillum (T. polycomum), P. carinifolium and P. praealtum (T. praealtum), P. cyanescens var. latifolium (T. schwackeanum), I. sapinii and P. strictissimum (T. strictissimum), and P. drosocarpum, P. gemmeum and P. viciniflorum (T. tenellum). We also indicate a new synonym under T. tenellum: P. imbelle. Typification notes and images of the type-specimens are presented.

Eriocaulaceae is a pantropical family of approximately 1200 species across 18 genera, with its highest diversity in the Neotropical region. Traditionally, the family has been divided into two subfamilies, Eriocauloideae and Paepalanthoideae, based on floral traits. Here, we use target‐capture sequencing of nuclear markers to test the monophyly of these subfamilies. Using the Angiosperms353 probe set, we analyzed data from 30 species, generating new sequences for 24 species, representing eight genera of Eriocaulaceae. Phylogenetic analyses using ASTRAL‐III and a concatenated maximum likelihood approach recovered three major clades, revealing that Paepalanthoideae is non‐monophyletic. Monosperma, a Pantepui‐endemic lineage, recently elevated to generic status, emerged as the sister group to the rest of the family. Our findings suggest that the ancestral Eriocaulaceae flower had a single‐whorled androecium, contrary to previous hypotheses. Additionally, this study highlights the non‐monophyletic nature of the broad circumscription of Paepalanthus. These results challenge long‐held assumptions about the evolutionary relationships within Eriocaulaceae, providing critical insight into its subfamilial and generic classification, and call for further research into the evolutionary history of the family.

O artigo atual visa apresentar um estudo sobre a espécie de bambu Guadua macrostachya Rupr, com o objetivo de desenvolver um protocolo eficiente de propagação in vitro para o bambu Guadua macrostachya Rupr, uma espécie nativa da Amazônia. O estudo foi realizado no Laboratório de Biotecnologia Vegetal da Empresa Brasileira de Pesquisa Agropecuária (Embrapa) na cidade de Belém, em parceria com o Museu Paraense Emílio Goeldi. Conclui-se que a manifestação bacteriana, fúngica e oxidação dos tecidos, no processo de estabelecimento in vitro, é considerada comum em diversas espécies de bambu e em Guadua macrostachya Rupr. É possível adotar o uso de 0,3% do fungicida nativo durante o processo de assepsia dos explantes, como uma medida suficiente para o controle da contaminação fúngica. Portanto, a manifestação de microrganismos é considerada um entrave recorrente durante o estabelecimento in vitro de bambu, tornando-se assim um desafio alcançar uma técnica eficiente para a produção de mudas em larga escala da espécie.