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1.
Nat Plants ; 8(2): 125-135, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35102275

RESUMO

The rapid Cretaceous diversification of flowering plants remains Darwin's 'abominable mystery' despite numerous fossil flowers discovered in recent years. Wildfires were frequent in the Cretaceous and many such early flower fossils are represented by charcoalified fragments, lacking complete delicate structures and surface textures, making their similarity to living forms difficult to discern. Furthermore, scarcity of information about the ecology of early angiosperms makes it difficult to test hypotheses about the drivers of their diversification, including the role of fire in shaping flowering plant evolution. We report the discovery of two exquisitely preserved fossil flower species, one identical to the inflorescences of the extant crown-eudicot genus Phylica and the other recovered as a sister group to Phylica, both preserved as inclusions together with burned plant remains in Cretaceous amber from northern Myanmar (~99 million years ago). These specialized flower species, named Phylica piloburmensis sp. nov. and Eophylica priscastellata gen. et sp. nov., exhibit traits identical to those of modern taxa in fire-prone ecosystems such as the fynbos of South Africa, and provide evidence of fire adaptation in angiosperms.


Assuntos
Âmbar , Rhamnaceae , Ecossistema , Fósseis , Mianmar
2.
PhytoKeys ; 172: 97-119, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33664610

RESUMO

The popularity of electronic identification keys for species identification has increased with the rapid technological advancements of the 21st century. Although electronic identification keys have several advantages over conventional textual identification keys and work well for charismatic species with large and clear morphological characters, they appear to be less feasible and less effective for species with cryptic morphology (i.e. small, obscure, variable characters and/or complicated structures associated with terminology that is difficult to interpret). This is largely due to the difficulty in presenting and illustrating cryptic morphological characters unambiguously. When taking into account that enigmatic species with cryptic morphology are often taxonomically problematic and therefore likely exacerbate the taxonomic impediment, it is clear that species groups with cryptic morphology (and all the disciplines dependent on their correct identification) could greatly benefit from a user-friendly identification tool, which clearly illustrates cryptic characters. To this end, the aim of this study was to investigate and develop best practices for the unambiguous presentation of cryptic morphological characters using a pilot interactive photographic identification key for the taxonomically difficult plant genus Thesium (Santalaceae), as well as to determine its feasibility. The project consisted of three stages: (1) software platform selection, (2) key construction and (3) key evaluation. The proposed identification key was produced with Xper3 software and can be accessed at http://www.xper3.fr/xper3GeneratedFiles/publish/identification/1330098581747548637/mkey.html. Methodologies relating to amongst others, character selection and delineation, visual and textual descriptions, key construction, character coding and key evaluation are discussed in detail. Seventeen best practices identified during this study are subsequently suggested for future electronic key compilation of species with cryptic morphology. This study indicates that electronic identification keys can be feasible and effective aids for the identification of species with cryptic morphological characters when the suggested best practices are followed.

3.
J Ethnopharmacol ; 256: 112745, 2020 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-32188571

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Many plant species representing the hemi-parasitic genus Thesium play important roles in communities around the globe as evidenced by the numerous ethnobotanical and contemporary uses, and pharmacological activities. However, no attempt has been made to amalgamate and analyze all of the available information. A comprehensive survey is needed to highlight knowledge gaps, as well as to determine the economic importance and commercial potential of the genus. AIMS OF THIS REVIEW: To provide a comprehensive report on the species diversity, geographical distribution, ethnobotany, contemporary uses, chemistry, pharmacology and toxicology of the genus Thesium, as well as to give insights into possible future research opportunities. MATERIALS AND METHODS: Literature on the ethnobotany, contemporary uses, chemistry and pharmacology of Thesium was gathered from standard search engines (Google, Google Scholar, PubMed, SciFinder and Scopus) using the phrase Thesium, as well as generic synonyms. Additional information came from relevant books, theses, patents and label information from herbarium specimens in the National Herbarium in Pretoria, South Africa. Information on geographical distributions was compiled from regional floras, regional revisions, original species descriptions and databases (GBIF, IPNI, Plants of the World online and The Plant List). Scientific names and synonyms were validated through www.plantsoftheworldonline.org. RESULTS: A total of 23 Thesium species, 17 from Africa and six from Asia, were found to have traditional and contemporary uses. Despite the near cosmopolitan distribution of the genus, no uses were recorded for Europe, Australia and North America. Thesium plants are most commonly used as medicines (18 species), functional foods and beverages (seven species), charms (six species) and crafts (three species), but also have several other minor uses. Charm uses were restricted to southern and East Africa, while several contemporary uses such as functional feeds and fodders, growth mediums and fertilizers and veterinary medicine were unique to Asia. Thesium chinense is by far the most utilized and versatile species with a total of 173 uses in nine use categories, followed by T. longifolium with 39 uses in six use categories. No specific trends were observed in the plant parts used. As a medicine Thesium is used to treat 137 ailments, predominantly reproductive and breast (22), respiratory tract (18), degenerative (11), digestive (11) and urinary (10) ailments. Chemical analyses are available for only eight species, with flavonoids, fatty acids and alkaloids as the main compounds. The potential influence of the host plants on the chemistry and pharmacology remains unexplored. The pharmacological activities of two species, T. chinense and T. viride, have been studied, while three other species are reported to be poisonous. Thesium chinense has analgesic, anti-inflammatory, anti-oxidation, chemopreventive, cytotoxic and other general therapeutic properties, and T. viride anti-bacterial activity. CONCLUSION: This study has highlighted the ethnobotanical, contemporary and pharmacological importance of Thesium and informed possible future research opportunities. While ample information is available on the traditional uses of the richly diverse African Thesium species, the few Asian species dominate the literature on contemporary uses and pharmacology, while relevant literature on species in the rest of the world is altogether lacking. In light of the popularity of Asian species as ingredients in contemporary medicines and products, further research is needed into African species and their uses, including potential commercial uses. As an important medicinal hemi-parasite in both Africa and Asia, the identities of ethnobotanically relevant species and their phytochemistry, pharmacology and toxicology remain underexplored and require more research attention.


Assuntos
Preparações de Plantas/química , Preparações de Plantas/farmacologia , Plantas Medicinais/química , Santalaceae/química , África Oriental , Animais , Ásia , Austrália , Etnobotânica/métodos , Etnofarmacologia/métodos , Europa (Continente) , Humanos , Medicina Tradicional/métodos , América do Norte
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