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Diospyros L. is a large genus of flowering plants predominantly distributed in the tropics. It comprises over 700 species globally and around 300 are believed to occur in South-East Asia. Many species are economically important and exploited for the production of ebony wood and persimmons, yet taxonomic information on the genus is incomplete and inconsistent due to its morphological and nomenclatural complexity. Revisions of Diospyros in continental and insular South-East Asia were conducted independently by different authors, occasionally with different names used for the same species, or different species being given the same name in different countries. During our ongoing study of the genus Diospyros in Indochina (Cambodia, Laos, Thailand and Vietnam), we identified several such instances. Here, we clarify the most commonly misidentified species, including 1) D. apiculata Hiern, D. strigosa Hemsl. and D. tamiriensis Lecomte; 2) D. bejaudii Lecomte and D. retrofracta Bakh.; 3) D. dictyoneura Hiern and D. hasseltii Zoll.; 4) D. borneensis Hiern and D. fecunda H.R.Fletcher. Lectotypifications are also made for D. brachiata King & Gamble var. lanceolata H.R.Fletcher, D. fecunda, D. similis Craib and D. strigosa.
During a taxonomic study of the species of Croton sect. Adenophylli occurring in Brazil, approximately 140 collections usually identified as Croton echioides, C. rhamnifolius or C. rhamnifolioides caught our attention due to the distinct morphology of vegetative and reproductive organs. After the analysis of these collections, we concluded that they represent a new species, C. sertanejus Sodré & M.J.Silva sp. nov., which was also corroborated by an anatomical study of their leaves. This new species can be differentiated by pseudomonopodial branching, leaves with petioles up to 1.7 cm long, 4–6 subsessile nectary glands and indumentum of sessile trichomes on both surfaces. Detailed descriptions, including details of leaf anatomy, are provided for C. sertanejus sp. nov. and C. echioides, its closely related species. We also formalize the synonymization of C. kalkmannii under C. echioides and re-evaluate the typification of these names, in order to better clarify their taxonomic status.
The Chapada dos Veadeiros National Park is a conservation unit established to preserve the highest savannahs of Central Brazil and their unique biodiversity. Eriocaulaceae are a relevant and conspicuous family in such high savannahs, but its diversity is poorly known, documented solely in general lists or in isolated efforts aimed at small groups. After a structured series of field expeditions and analysis of specimens from the relevant herbaria, we provide nomenclatural novelties, a first identification key, and an illustrated checklist for the species of Paepalanthoideae (Eriocaulaceae) in the area. We recorded 42 species of Paepalanthoideae from the Chapada dos Veadeiros National Park: Actinocephalus (Körn.) Sano (2 spp.), Comanthera L.B.Sm. (1 sp.), Paepalanthus Mart. (24 spp.), and Syngonanthus Ruhland (15 spp.). Actinocephalus brevifolius Trovó & Echtern. sp. nov. and P. irwinii Trovó & Echtern. sp. nov. are newly described species and P. politus Trovó stat. et nom. nov. is a variety of P. elongatus (Bong.) Körn. raised to the species status with a new name. The generic and specific composition shows predominance of Paepalanthus and Syngonanthus, and with a low representation of Actinocephalus and Comanthera, as expected, outside of the Espinhaço Range. More than 50% of the species (22 spp.) are endemic to the area and 25 species are endemic to Central Brazil, the area being the main center of diversity for dimerous-flowered groups. The non-endemic diversity is a combination of widespread species and marginal distribution of species typical from the Amazon and southeastern savannahs. The species are unevenly distributed in the area, with their occurrence correlated to altitude, water availability, and lithology. We reinforce that the savannahs from Central Brazil are a secondary center of diversity for Eriocaulaceae, playing a central role in the conservation of an unique and irreplaceable piece of its diversity and the Cerrado biome as well.
Two new species of Sonerila Roxb. (Melastomataceae), S. erectifolia Phonep., Soulad. & Tagane sp. nov. from southern Laos, and S. souvannii Phonep. & Soulad. sp. nov. from central Laos, are described and illustrated. Comparisons with morphologically similar species are presented, along with ecological information and preliminary conservation status. A key to the species of Sonerila in Laos is also provided.
The current status of exotic freshwater vascular plants in Australia - a systematic description
(2018)
Freshwater systems are considered particularly vulnerable to human impact, through habitat modification, changes to water regimes and quality, invasion by exotic species and climate change. Using various records, we conducted a descriptive analysis of the naturalised freshwater plant species in Australia. There are 63 freshwater plant species belonging to 45 genera and 26 families naturalised in Australia with the dominant families being Cyperaceae, Poaceae and Plantaginaceae. More than 40% of these species are categorised as either invasive or declared weeds, the majority being perennial wetland marginal plants. They originated from all the inhabited continents with most of the species being native to Europe, South America and North America. The greatest number of species are currently found in New South Wales (90%), Queensland (68%) and Victoria (65%); the ornamental aquarium plant trade was identified as the main introduction pathway. Most species are clonal plants with flexible modes of reproduction and multiple dispersal vectors. We conclude that exotic plant species are now an important component of Australia’s freshwater systems and that ongoing monitoring of their status, distribution and impact should be a high priority in light of the increasing influence of anthropogenic factors including climate change.
Since the last comprehensive publication on Burkina Faso’s flora, further species have been documented in publications and online resources. These thirteen species are listed here with notes on ecology, use and distribution. The number of vascular plants known for Burkina Faso has therefore reached 2080 species.
China has shown a rapid economic development in recent decades, and several drivers of this change are known to enhance biological invasions, a major cause of biodiversity loss. Here we review the current state of research on plant invasions in China by analyzing papers referenced in the ISI Web of Knowledge. Since 2001, the number of papers has increased exponentially, indicating that plant invasions in China are an emerging hot topic in invasion science. The analyzed papers cover a broad range of methodological approaches and research topics. While more that 250 invasive plant species with negative impacts have been reported from China, only a few species have been considered in more than a handful of papers (in order of decreasing number of references: Spartina alterniflora, Ageratina adenophora, Mikania micrantha, Alternanthera philoxeroides, Solidago canadensis, Eichhornia crassipes). Yet this selection might rather reflect the location of research teams than the most invasive plant species in China. Considering the previous achievements in China found in our analysis research in plant invasions could be expanded by (1) compiling comprehensive lists of non-native plant species at the provincial and national scales and to include species that are native to one part of China but non-native to others in these lists; (2) strengthening pathways studies (primary introduction to the country, secondary releases within the country) to enhance prevention and management; and (3) assessing impacts of invasive species at different spatial scales (habitats, regions) and in relation to conservation resources.