Taxonomia e cariologia do gênero Isoetes L. nas Regiões Sul e Sudeste do Brasil

Resumo: Isoetes L. (Isoetaceae) é uma licófita com distribuição quase que cosmopolita, com aproximadamente 350 espécies. Nas regiões sul e sudeste do Brasil a maioria das espécies é conhecida de um número bastante limitado de coleções. No presente trabalho é apresentado o tratamento taxonômico para as espécies desta área. Ao todo foram registradas 15 espécies, 12 delas restritas a área de estudo: Isoetes bradei, I. brasiliensis, I. goebelii, I. martii, I. maxima, I. mourabaptistae, I. organensis, I. quiririensis, I. ramboi, I. sehnemii, I. spannagelii e I. ulei. Isoetes baculata, I. gigantea e I. weberi são as três espécies que também ocorrem em outras áreas do Brasil e América do Sul. São também apresentados chave de identificação, descrições, comentários, ilustrações dos esporos e mapas de distribuição geográfica

A list of land plants of Parque Nacional do Caparaó, Brazil, highlights the presence of sampling gaps within this protected area

Brazilian protected areas are essential for plant conservation in the Atlantic Forest domain, one of the 36 global biodiversity hotspots. A major challenge for improving conservation actions is to know the plant richness, protected by these areas. Online databases offer an accessible way to build plant species lists and to provide relevant information about biodiversity. A list of land plants of “Parque Nacional do Caparaó” (PNC) was previously built using online databases and published on the website "Catálogo de Plantas das Unidades de Conservação do Brasil." Here, we provide and discuss additional information about plant species richness, endemism and conservation in the PNC that could not be included in the List. We documented 1,791 species of land plants as occurring in PNC, of which 63 are cited as threatened (CR, EN or VU) by the Brazilian National Red List, seven as data deficient (DD) and five as priorities for conservation. Fifity-one species were possible new ocurrences for ES and MG states

Cheklist das samambaias e licófitas das Florestas Alto-montanas do Parque Estadual Pico Paraná, Brasil

Orientador: Renato GoldenbergCoorientador: Paulo LabiakMonografia (Bacharelado) - Universidade Federal do Paraná. Setor de Ciências Biológicas. Curso de Graduação em Ciências BiológicasResumo : Este trabalho apresenta um levantamento das espécies de samambaias e licófitas do Parque Estadual Pico Paraná (PEPP). O Parque ocupa uma área de 4.333,84 ha, com trilhas que percorrem de 885 a 1.877 m altitude, situado nos municípios de Antonina e Campina Grande do Sul, sendo o Pico Paraná o ponto culminante da região Sul do Brasil. A vegetação consiste em Floresta Ombrófila Densa Montana e Alto-montana, com campos de altitude nas porções mais elevadas. Para este trabalho foram consideradas apenas as espécies com ocorrência acima de 1.000 m altitude, onde se concentram as florestas alto-montanas do Parque. Foram registradas 134 espécies distribuídas em 56 gêneros e 18 famílias, sendo as mais representativas Polypodiaceae (29 ssp.); Hymenophyllaceae (19 ssp.); Dryopteridaceae (16 ssp.); Aspleniaceae (11 ssp.); Pteridaceae (10 spp.) e Lycopodiaceae (9 spp.). Dentre as espécies encontradas, 41 ocorrem somente no Brasil, sendo 29 dessas endêmicas das regiões Sudeste e Sul. Destacam-se espécies como Alsophila capensis (L.f.) J.Sm., Eriosorus insignis (Kuhn) A.F.Tryon, bastante raras no Sul do Brasil, e Plagiogyria fialhoi (Fée & Glaz. ex Fée) Copel., novo registro para o estado do Paraná. Houve também cinco registros inéditos para a região Sul do Brasil como Doryopteris paradoxa (Fée) Christ, Huperzia nuda (Nessel) B.Øllg. & P.G.Windisch., Hypolepis rugosula (Labill.) J.Sm., Fée, Lellingeria myosuroides (Sw.) A.R.Sm. & R.C.Moran e Thelypteris tamandarei (Rosenst.) Ponce. Assim, a área de estudo demonstra ser um local de grande importância fitogeográfica com altas taxa de endemismo, sendo um reduto de interesse maior para a proteção da diversidade das samambaias e licófitas

Phylogeny and taxonomy of the South American genus Isoetes L.\textit {Isoetes L.}

Das Thema meiner Dissertation ist die Diversität, die Morphologie, die molekulare Phylogenie und die Biogeographie der Gattung $\it Isoetes$. Die Studie ist in fünf Teile gegliedert. Im ersten Teil werden $\textit {Isoetes serracarajensis}$ und $\textit {I. cangae}$ beschrieben und mit ähnlichen Arten verglichen. Im zweiten Teil wird eine aktuelle Liste aller lebenden Arten vorgestellt. Der dritte Teil zeigt, dass die Neotropischen $\it Isoetes$ in zwei monophyletischen Claden zu finden sind: In der Core Gondwanischen Clade spielt Vikarianz eine wichtige Rolle bei der Divergenz der Gruppen. Die Diversifikation in der Amerikanischen Clade fand zur Zeit der Schließung des Amerikanischen Seeweges um 13 Mya statt. Im vierten Teil werden die taxonomischen und molekularen Studien dargestellt, die mit $\it Isoetes$ aus dem Südosten Südamerikas durchgeführt wurden. Im letzen Teil werden schließlich zwei neue Arten beschrieben. Außerdem werden die morphologischen Merkmale von verschiedenen $\it Isoetes$-Arten in der Phylogenie abgebildet

Organellar-genome analyses from the lycophyte genus Isoetes L. show one of the highest frequencies of RNA editing in land plants

RNA editing is a post-transcriptional process that challenges the central dogma of molecular biology by modifying RNA sequences, introducing nucleotide changes at specific sites, and generating functional diversity beyond the genomic code, especially when it concerns organellar transcripts. In plants, this phenomenon is widespread, but its extent varies significantly among species and organellar genomes. Among land plants, the heterosporous lycophytes (i.e., Isoetes and Selaginella) stand out for their exceptionally high numbers of RNA-editing sites, despite their morphological stasis and ancient lineage. In this study, we explore the complete set of organellar protein-coding genes in the aquatic plant group Isoetes, providing a detailed analysis of RNA editing in both the mitochondrial and plastid genomes. Our findings reveal a remarkable abundance of RNA editing, particularly in the mitochondrial genome, with thousands of editing sites identified. Interestingly, the majority of these edits result in non-silent substitutions, suggesting a role in fine-tuning protein structure and function. Furthermore, we observe a consistent trend of increased hydrophobicity in membrane-bound proteins, supporting the notion that RNA editing may confer a selective advantage by preserving gene functionality in Isoetes. The conservation of highly edited RNA sequences over millions of years underscores the evolutionary significance of RNA editing. Additionally, the study sheds light on the dynamic nature of RNA editing, with shared editing sites reflecting common ancestry whereas exclusive edits matching more recent radiation events within the genus. This work advances our understanding of the intricate interplay between RNA editing, adaptation, and evolution in land plants and highlights the unique genomic features of Isoetes, providing a foundation for further investigations into the functional consequences of RNA editing in this enigmatic plant lineage

Ferns and Lycophytes from the Estação Ecológica Serra Geral do Tocantins: a contribution to the flora of the Jalapão, Brazil

Abstract This study contributes to the flora of ferns and lycophytes, also referred to as pteridophytes, from the Estação Ecológica Serra Geral do Tocantins (EESGT), which is part of the Jalapão region in Tocantins. Although Jalapão is one of the largest protected areas in the Cerrado vegetation of Northern Brazil, its biodiversity has, thus far, been poorly reported in the literature. Therefore, fieldwork was recently carried out at EESGT in different habitats. Our collections and data from digital repositories included 31 ferns and four lycophyte species belonging to 20 genera of 15 families. Despite occupying only a small fraction of the landscape, forests concentrate most pteridophyte diversity, reinforcing their importance for the conservation of this group within the Cerrado. Eleven species are new records for Tocantins, one is new for Bahia, and one was recently described (Anemia areniticola). In addition to a list of all taxa, we provide illustrations and an identification key to encourage further studies on this often-neglected component of Cerrado flora

Anatomical studies of Brazilian Amazonian Isoëtes species: inferences on habitat adaptation

Abstract Isoëtes is a cosmopolitan genus of aquatic lycophytes, containing more than 200 species. In Brazil, the genus comprises 29 species, with three occurring in Pará state, Amazon. Isoëtes cangae and I. serracarajensis are endemic to the ferruginous outcrops of Serra dos Carajás, and I. amazonica occurs on the inundated shores of the Tapajós River. Despite the great diversity of quillworts in South America, their anatomy remains unknown. This study discusses Brazilian Amazon species’ leaf and root anatomical traits in relation to habitat and genetic diversity. The amphibious I. amazonica and I. serracarajensis were observed to have similar stomata and cuticular ornamentations. Isoëtes cangae, a fully aquatic species, had smaller epidermal cells and a smooth cuticle and showed slight differences regarding the lacuna diaphragm. The genetically closer species from Carajás both lacked peripheral fiber strands on the leaves. Our study complements current knowledge regarding the morphoanatomy of Amazonian species and provides a better understanding of their biology, contributing to the development of conservation strategies for these species