A robust generic classification for Amaryllidaceae has remained elusive mainly due to the lack of unequivocal diagnostic characters, a consequence of highly canalized variation and a deeply reticulated evolutionary history. A consensus classification is proposed here, based on recent molecular phylogenetic studies, morphological and cytogenetic variation, and accounting for secondary criteria of classification, such as nomenclatural stability. Using the latest sutribal classification of Hippeastreae (Hippeastrinae and Traubiinae) as a foundation, we propose the recognition of six genera, namely Eremolirion gen. nov., Hippeastrum, Phycella s.l., Rhodolirium s.str., Traubia, and Zephyranthes s.l. A subgeneric classification is suggested for Hippeastrum and Zephyranthes to denote putative subclades. In Hippeastrum, we recognize H. subg. Hippeastrum and H. subg. Tocantinia. In Zephyranthes, Z. subg. Eithea, Z. subg. Habranthus, Z. subg. Myostemma (= core Rhodophiala clade), Z. subg. Neorhodophiala subg. nov., and Z. subg. Zephyranthes are recognized. Descriptions, synonymy, taxonomic keys, and new combinations are provided for each genus and subgenus.

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Recebido em 20/12/07; aceito em 4/6/08; publicado na web em 5/11/08 ANTIOXIDANT AND ANTICOLINESTERASIC EFFECTS OF Hippeastrum SPECIES (AMARYLLIDACEAE). Amaryllidaceae family is an important source of bioactive molecules and considering the taxonomic relationships, it is relevant to investigate the genus Hippeastrum. Thus, the aim of this work was to determine antioxidant and anticholinesterasic activities of Hippeastrum morelianum, Hippeastrum psittacinum and Hippeastrum santacatarina. Both antioxidant and acetylcholinesterasic activities of extracts were determinated by bioautography as 10 mg/mL and 0.1 mg/mL, respectively. The antioxidant activity of alkaloid lycorine, determinated spectrophotometrically with DPPH, indicated an IC 50 value of 0.326 mM.Keywords: Amaryllidaceae; antioxidant; anticholinesterasic. IntrodUçãoA etiologia da Doença de Alzheimer (DA) permanece desconhecida, mas estudos post mortem têm mostrado que a doença é caracterizada pela diminuição da função colinérgica no cérebro.1 Os mais modernos medicamentos utilizados para tratar os sintomas da DA elevam os níveis de acetilcolina pela inibição da enzima acetilcolinesterase (AChE). Ensaios desenvolvidos para detectar esta atividade estão sendo amplamente utilizados para avaliar um grande número de plantas utilizadas popularmente para melhorar a memória. Sabe-se também que o dano causado por espécies reativas de oxigênio, atualmente, é considerado um fator contribuinte de diversas doenças, incluindo a DA.3 Assim, identificar o potencial antioxidante de uma substância pode credenciá-la a ser uma molécula bioativa mais completa quando se considera o conjunto de suas propriedades. Dessa forma, é adequada a associação de ambos os ensaios para um estudo bioguiado mais eficiente.Na busca por novos fármacos, os produtos naturais destacam-se pela diversidade estrutural e, assim, as plantas são candidatas importantes para screening de novos compostos bioativos. Ao considerar as informações botânicas e quimio-taxonômicas, a eleição das plantas a serem investigadas torna-se mais selecionada. Considerando esse conjunto de fatores, a família Amaryllidaceae, particularmente, desponta como uma fonte promissora de novas substâncias bioativas, justificando a avaliação dos gêneros presentes no Brasil.O alcalóide galantamina foi, inicialmente, isolado de Galanthus woronowii, mas atualmente é obtido a partir de Narcissus sp. e Leucojum aestivum, assim como sinteticamente. A partir da descoberta deste alcalóide enquanto potente inibidor da enzima AChE, sua aprovação pelo FDA (Food and Drug Administration) em 2001 para comercialização e, conseqüentemente, importante utilização na DA, o interesse no estudo químico e farmacológico da família Amaryllidaceae vem aumentando exponencialmente. 4,5 Um screening do extrato bruto e das frações enriquecidas em alcalóides obtidas durante a extração ácido-base auxilia no direcionamento das investigações de isolamento e elucidação estrutural dessas substâncias, bem como contribui para a triagem de gêneros e espécies promissoras...

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.

Nine Brazilian Amaryllidaceae species were studied for their alkaloid composition and acetylcholinesterase (AChE) inhibitory activity via GC-MS and a modified Ellman assay, respectively. A total of thirty-six alkaloids were identified in these plants, of which Hippeastrum papilio and H. glaucescens exhibited the highest galanthamine content and the best IC 50 values against AChE. Furthermore, Hippeastrum vittatum and Rhodophiala bifida also showed notable AChE inhibitory effects. X-ray crystallographic data for four galanthamine-type compounds revealed significant differences in the orientation of the N-methyl group, which are shown to be related to AChE inhibition.