Taxonomy of Atlantic Central African orchids 3. A new species of Bulbophyllum Thouars (Orchidaceae) from the Monts de Cristal, Gabon

Two specimens of an apparently new Bulbophylum species were found in the Monts de Cristal, Gabon. They have a unique leaf shape among the species of this genus in Continental Africa. The flower shares the general morphology of Bulbophyllum saltatorium, one of the most common members of Bulbophyllum in Central Africa. Eight other taxa of the Continental Aafrican Bulbophyllum possess unifoliate pseudobulbs and long hairs on the lip. Comparison with them indicates that the new collections from Gabon represent a distinctive species, not yet known in the genus. we describe it here as Bulbophyllum pauwelsianum. The distinguishing features of the species include its leaves, which are pendant, coriaceous, linear, semiterete and v-shaped in transverse section, and its sepals, which possess relatively long hairs on their margins. A table of the taxonomic treatments of the nine Continental African Bulbophyllum taxa considered here is included. A taxonomic key and a table of the diagnostic characters of these nine taxa are given to facilitate identification. The new species is restricted to lowland forests of the Monts de Cristal in Gabon. A preliminary assessment of the conservation status, using the IuCN red list Categories and Criteria is provided. © 2014 Magnolia Press.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Taxonomy of Atlantic Central African orchids, 6: three new species of Angraecum sect. Afrangraecum (Orchidaceae, Angraecinae) from Gabon and São Tomé

International audienceThree new species of Angraecum sect. Afrangraecum from Central Africa are here described and illustrated. They are morphologically similar to A. affine and A. cribbianum. Two of them, A. gereauanum and A. geerinckianum, are only known from Massif du Chaillu in Gabon and appear to be closely related based on morphological and preliminary molecular evidence. The third species, A. oliveirae, is endemic to São Tomé. A dichotomous key to all fourteen species of A. sect. Afrangraecum and a table with the distinguishing characters of the three new species and closely allied taxa are provided. A preliminary assessment of the conservation status of the new species is also presented, using the IUCN Red List categories and criteria

A single origin of leaflessness in Afro‐Malagasy angraecoids (Orchidaceae, Angraecinae)

International audienceMicrocoelia and the monospecific Taeniorrhiza and Chauliodon are notable among Afrotropical angraecoid orchids for being leafless. However, the affinity among these genera was not addressed in previous molecular phylogenetic studies, thus precluding the understanding of how many times has leaflessness evolved in angraecoids. The discovery of an additional species ascribable to Taeniorrhiza in Gabon, and a revision of all material referrable to this genus in herbarium collections, created the possibility to investigate the phylogenetic position of Taeniorrhiza relative to Microcoelia and Chauliodon. Based on phylogenetic inference using ITS-1 and two plastid regions (matK/trnK, trnL-trnF), and including 20 of the 34 species of Microcoelia recognised prior to our study, we here demonstrate that Taeniorrhiza and Chauliodon are deeply imbedded in Microcoelia, and are thus treated here as synonyms of the last. Accordingly, we describe the novelty from Gabon as a new species of Microcoelia: Microcoelia nguemae sp. nov. The new species is illustrated with colour photographs, and also with line drawings. Its preliminarily IUCN conservation status is provided. The novelty is notable for the dorsiventrally asymmetric distribution of pneumathodes along its roots and for bearing the longest lip spur in this Afro-Malagasy epiphytic genus. The new phylogenetic framework suggests a single origin of leaflessness in Afrotropical angrecoids and reveals the informative value of the rostellum to reconstruct relationships within Microcoelia. This serves as the basis of a newly proposed sectional treatment for Microcoelia, recognising 37 species, one new section, a new status for the defunct genus Encheiridion and the redefinition of Microcoelia sect. Microcoelia and sect. Brachygloss

Peri-urban conservation in the Mondah forest of Libreville, Gabon: Red List assessments of endemic plant species, and avoiding protected area downsizing

Urban development is an increasing threat to the integrity of formerly remote protected areas, in some cases resulting in their downgrading, downsizing or degazetting. One-quarter of previously remote protected areas are now within 17 km of a city and thus face the threat of urbanization. Here we describe a case of avoided downgrading, downsizing and degazetting of a protected area in the Mondah forest of Gabon, north of Libreville. Since its creation in 1934 the Forêt Classée de la Mondah has been downsized regularly, losing 40% of its area over 80 years. During this time the forest surrounding the Forêt Classée was subject to usage for urban and peri-urban needs, including agriculture, sand extraction, collection of medicinal plants, ceremonies, and housing construction. In 2010 the area was threatened with further downsizing. The presence of narrowly endemic plant species in the area was suspected, and mapping and evaluation of these species was proposed in an effort to maintain the protected area boundaries. Botanical field work, including ex situ conservation measures and participant observation in nearby forest communities, was conducted; 24 endemic species, all threatened by urbanization, were evaluated using the criteria for the IUCN Red List of Threatened Species. The borders of the protected area were maintained because of its role in maintaining irreplaceable habitat for threatened species. The area was renamed Raponda Walker Arboretum in 2012

Variability studies of active galactic nuclei from the long-term monitoring program with the Cherenkov Telescope Array

International audienceBlazars are active galactic nuclei (AGN) with a relativistic jet oriented toward the observer. This jet is composed of accelerated particles which can display emission over the entire electromagnetic spectrum. Spectral variability has been observed on short- and long-time scales in AGN, with a power spectral density (PSD) that can show a break at frequencies below the well-known red-noise process. This break frequency in the PSD has been observed in X-rays to scale with the accretion regime and the mass of the central black hole. It is expected that a break could also be seen in the very-high-energy gamma rays, but constraining the shape of the PSD in these wavelengths has not been possible with the current instruments. The Cherenkov Telescope Array (CTA) will be more sensitive by a factor of five to ten depending on energy than the current generation of imaging atmospheric Cherenkov telescopes, therefore it will be possible with CTA to reconstruct the PSD with a high accuracy, bringing new information about AGN variability. In this work, we focus on the AGN long-term monitoring program planned with CTA. The program is proposed to begin with early-start observing campaigns with CTA precursors. This would allow us to probe longer time scales on the AGN PSD

P38. More than twenty years of orchid ex situ conservation in Africa and Madagascar

International audienceOrchid conservation represents a significant challenge inTropical Africa and Madagascar, areas in which habitats are facing increasing pressure from agriculture, mining and logging activities. In these regions, a large part of the epiphyte flora is composed of orchids, most of which, when lacking flowers when encountered in the field, are impossible to identify. However, accurate identification is essential for developing conservation strategies since about 69% of tropical Africanand Malagasy orchids are potentially threatened. To overcome this identification problem, a shadehouse cultivation system was developed in São Tomé in 1997 and has now been extended across Continental Africa and Madagascar, providing a powerful tool for conducting thorough orchid inventories since most epiphytes can easily be brought into cultivation and grown to produce fertile, identifiable material. The network currently counts 12 shadehouses in sixcountries and, to date, 32,013 living orchids collected in the field have been grown, representing about 500 species, from which >23,764 herbarium specimens have been collected, most associated with silicagel-preserved material and photos. This material has been usedto describe 41 previously unknown species and to assess the conservation status of hundreds of species in three key areas (West Africa, Central Africa and Madagascar), while also leading to the publication of 44 articles in taxonomy, phylogeny, floristics and for the general public. Initially designed to facilitate orchid inventory and identification, the shadehouses now contribute to orchid conservation by protecting plants in safe, controlled conditions, producing material for seeds banking. They also offer valuable training opportunities for young botanists, thereby contributing to in-country capacity building. Key factors that explain the success of this shadehouse network and its long-term survival are the support provided by reliable local partners, the involvement of young botanists and students, and the development of new techniques to grow thousands of living orchids successfully and cost-effectivel