Grass survey of the Itremo Massif records endemic central highland grasses

Despite the substantial area covered by grasslands in Madagascar (65%), the taxonomy of the grasses (Poaceae), which represent the main plant component of these vegetation types, is still understudied. Inventories and detailed specimen identification work from 1 2 localities in the Itremo Massif Protected Area allowed us to compile a list of grasses present in the area. In total, members of eight subfamilies, 56 genera, and 99 species have been recorded from the Itremo Massif. Grasslands cover 75% of the Itremo Massif Protected Area and are dominated by Panicoideae (65%) and by C4 plants. The genera Eragrostis and Panicum, with nine and eight species respectively, are the best represented genera in Itremo. Eragrostis betsileensis and Tristachya betsileensis are the two species known to be local endemics. Twenty species are endemic to the central highlands, and a further 1 4 species are restricted to Madagascar. Five ecological groups of grasses were identified in the Itremo Massif: shade species in gallery forests, open wet area species, fire grasses, anthropogenic disturbance associated grasses and rock-dwelling grasses. Grasslands of the Itremo Massif are likely to be at least partly natural as shown by their richness in terms of endemic and native grass species. Conservation of such grasslands is thus an important issue, not only for grasses but for all species that inhabit these open canopy habitats

Grasses of the Isalo National Park, Madagascar – checklist, origins, and significance

Grasses are one of the best documented plant families worldwide in terms of taxonomy, but they are still poorly known in Madagascar. Our understanding of their diversity remains incomplete since grasses and grasslands are assumed by many tobe weeds and degraded wastelands. This project aimed to list thegrasses in Isalo National Park (NP) in order to understand theirdiversity and endemicity, as well as the history of Isalo’s grasslands. Examination of herbarium specimens and new field inventories allowed us to confirm 589 records of grass occurrences in ourstudy area. They were assigned to 112 species, of which 38 species are new records for Isalo NP. The Isalo grass flora includes seven of the eleven Poaceae subfamilies present in Madagascar and is particularly rich in Panicoideae, which make up 65% of the species. Nearly 22% of the grass species of Isalo are endemic to Madagascar, of which three species and one variety are restricted to Isalo massif, including two unusual ground cover species Tristachya humbertii A.Camus and Tristachya [Isalus isalensis]. Open grasslands harbour the highest diversity of grass species, followed closely by riparian forests. The history of the management of Isalo NP by the Bara people, as well as the endemism and the native origin of its grasses and  other species are consistent with an ancient origin of Isalo’s ecosystems. We urge that the conservation of Isalo’s grassy ecosystems, as well as that  of the plants and animals that inhabit them be prioritized.Les graminées sont parmi les familles de plantes les mieux documentées au niveau mondial en termes de taxonomie, mais sont encore mal  connues à Madagascar. Notre compréhension de leur diversité reste incomplète, vu que les graminées et les savanes sont considérées par beaucoup comme des mauvaises herbes et des friches dégradées. Ce projet visait à établir une liste des graminées connues du Parc National (PN) de l’Isalo, afin de comprendre leur diversité et leur endémicité, ainsi que l’histoire des écosystèmes herbeux de l’Isalo. L’examen des spécimens d'herbiers et les nouveaux inventaires sur terrains nous ont permis de générer 589 occurrences de graminées de notre site d’étude. Elles ont été  attribuées à 112 espèces de Poaceae, dont 38 sont de nouvelles collectes pour le massif de l’Isalo. La flore herbacée du massif de l'Isalo comprend  sept des onze sous-familles de Poaceae présentes à Madagascar et est particulièrement riche en Panicoideae qui représentent 65% des espèces.  Près de 22% des espèces de graminées de l’Isalo sont endémiques de Madagascar, dont trois espèces et une variété sont restreintes à Isalo, y  compris les deux espèces de plantes couvre-sols inhabituelles Tristachya humbertii A.Camus et Tristachya [Isalus isalensis]. Les prairies ouvertes  abritent la plus grande diversité d'espèces de graminées, suivies de près par les forêts ripicoles. L’histoire de la gestion du PN de l’Isalo par les  habitants de la région du groupe Bara, ainsi que l’endémisme et l’origine autochtone de ses graminées et autres espèces sont cohérents avec une  origine ancienne des écosystèmes de l’Isalo. Nous préconisons instamment que la conservation de ces prairies et savanes de l'Isalo, ainsi que les plantes et les animaux qui les habitent soit priorisée

Madagascar’s extraordinary biodiversity: Threats and opportunities

Madagascar's unique biota is heavily affected by human activity and is under intense threat. Here, we review the current state of knowledge on the conservation status of Madagascar's terrestrial and freshwater biodiversity by presenting data and analyses on documented and predicted species-level conservation statuses, the most prevalent and relevant threats, ex situ collections and programs, and the coverage and comprehensiveness of protected areas. The existing terrestrial protected area network in Madagascar covers 10.4% of its land area and includes at least part of the range of the majority of described native species of vertebrates with known distributions (97.1% of freshwater fishes, amphibians, reptiles, birds, and mammals combined) and plants (67.7%). The overall figures are higher for threatened species (97.7% of threatened vertebrates and 79.6% of threatened plants occurring within at least one protected area). International Union for Conservation of Nature (IUCN) Red List assessments and Bayesian neural network analyses for plants identify overexploitation of biological resources and unsustainable agriculture as themost prominent threats to biodiversity. We highlight five opportunities for action at multiple levels to ensure that conservation and ecological restoration objectives, programs, and activities take account of complex underlying and interacting factors and produce tangible benefits for the biodiversity and people of Madagascar

Madagascar’s extraordinary biodiversity: Evolution, distribution, and use

Madagascar's biota is hyperdiverse and includes exceptional levels of endemicity. We review the current state of knowledge on Madagascar's past and current terrestrial and freshwater biodiversity by compiling and presenting comprehensive data on species diversity, endemism, and rates of species description and human uses, in addition to presenting an updated and simplified map of vegetation types. We report a substantial increase of records and species new to science in recent years; however, the diversity and evolution of many groups remain practically unknown (e.g., fungi and most invertebrates). Digitization efforts are increasing the resolution of species richness patterns and we highlight the crucial role of field- and collections-based research for advancing biodiversity knowledge and identifying gaps in our understanding, particularly as species richness corresponds closely to collection effort. Phylogenetic diversity patterns mirror that of species richness and endemism in most of the analyzed groups. We highlight humid forests as centers of diversity and endemism because of their role as refugia and centers of recent and rapid radiations. However, the distinct endemism of other areas, such as the grassland-woodland mosaic of the Central Highlands and the spiny forest of the southwest, is also biologically important despite lower species richness. The documented uses of Malagasy biodiversity are manifold, with much potential for the uncovering of new useful traits for food, medicine, and climate mitigation. The data presented here showcase Madagascar as a unique living laboratory for our understanding of evolution and the complex interactions between people and nature. The gathering and analysis of biodiversity data must continue and accelerate if we are to fully understand and safeguard this unique subset of Earth's biodiversity

958. Euphorbia geroldii.

Euphorbia geroldii Rauh (Euphorbiaceae), one of the endemic Euphorbs in Madagascar is illustrated and described. In the wild it occurs in the dry forests of northern Madagascar, but with its red bright inflorescences the species is also cultivated as an ornamental

Taxonomic revision of Phyllanthus (Phyllanthaceae) in Madagascar and the Comoro Islands IV: subgenus Anisonemoides section Pseudogomphidium and incertae sedis

This paper is the fourth part of the taxonomic revision of the genus Phyllanthus in Madagascar and the Comoro Islands. Here we treat Pseudogomphidium Ralim. & Cable sect. nov. consisting of nine species that we misplaced in the subgenus Gomphidium (Baill.) G.L.Webster in our previous paper. Two species are new to science: Phyllanthus razakamalalae Ralim. & Cable, sp. nov. and P. ankirindrensis Ralim. & Cable, sp. nov. We also treat three unplaced species: P. analamerae Leandri, P. coluteoides Müll.Arg. and P. vergens Baill. An identification key, descriptions, distribution maps and IUCN Red List assessments are provided

Madagascar: A Biodiversity hotspot still revealing its botanical treasures.

The status of Madagascar's plant diversity is briefly reviewed, together with a consideration of the key threats and approaches used in conserving this unique flora. The role of the Kew Madagascar Conservation Centre is reviewed in relation to species discovery and conservation

A monograph of the African and Madagascan species of Cyperus sect. Incurvi (Cyperaceae)

Cyperus sect. Incurvi (Cyperaceae) contains 31 species worldwide, with important continental radiations in Australasia, Tropical Africa and Madagascar, and the Neotropics. Here, a monograph of the African and Madagascan species of Cyperus sect. Incurvi is presented, including descriptions, illustrations, synonymy, notes on habitat and ecology, geographic distribution ranges and conservation assessments. Our results identify eight species of Cyperus sect. Incurvi endemic to Madagascar, and a further three species native to Tropical Africa. Seven species of Cyperus sect. Incurvi have been typified herein. Six rare Madagascan endemics are assessed as threatened with extinction