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Summary: Cynorkis mammuthus Hermans & P.J.Cribb from Madagascar was formally described in 2017 from an unidentified herbarium specimen and was thought to be extinct until it was recently found flourishing in northern Madagascar. It is illustrated here and a full description, history and conservation assessment are provided. It is compared with similar species from the region, especially Cynorkis elephantina. [ABSTRACT FROM AUTHOR]

Summary: Cynorkis christae Hermans, Andriant. & Sieder, from Madagascar was first described a few years ago; it has the largest flowers in the genus. It is compared with similar species from the region; a full description, history, conservation assessment and detailed illustrations are provided. [ABSTRACT FROM AUTHOR]

Summary: Cynorkis aconitiflora Hermans, Andriant. & Sieder from Madagascar was formally described in 2017. It is illustrated here and a full description, history and conservation assessment are provided. It is compared with similar species from the region. [ABSTRACT FROM AUTHOR]

Summary: Cynorkis elephantina Hermans, Andriant. & Sieder from Madagascar was formally described in 2017. It is illustrated here and a full description, history and conservation assessment are provided. It is compared with similar species from the region, especially Cynorkis mammuthus Hermans & P.J. Cribb. [ABSTRACT FROM AUTHOR]

Summary: Cynorkis kiehnii Hermans, Sieder & Prehsler from Madagascar was first described in 2020. It is illustrated here; a full description and conservation assessment are provided. It is compared with similar species from the region, especially Cynorkis elephantina and C. mammuthus. [ABSTRACT FROM AUTHOR]

Summary: Angraecum longicalcar (Bosser) Senghas is illustrated. Details of its distribution and conservation are given, accompanied by a watercolour painting, line drawing and photographs. [ABSTRACT FROM AUTHOR]

Societal Impact Statement: There is increasing awareness that plants and fungi, as natural solutions, can play an important role in tackling ongoing global environmental challenges. We illustrate how understanding current and projected threats to plants and fungi is necessary to manage and mitigate risks, while building awareness of gaps and bias in current assessment coverage is essential to adequately prioritize conservation efforts. We highlight the state of the art in conservation science and point to current methods of assessment and future studies needed to mitigate species extinction. Summary: Plant and fungal biodiversity underpin life on earth and merit careful stewardship in an increasingly uncertain environment. However, gaps and biases in documented extinction risks to plant and fungal species impede effective management. Formal extinction risk assessments help avoid extinctions, through engagement, financial, or legal mechanisms, but most plant and fungal species lack assessments. Available global assessments cover c. 30% of plant species (ThreatSearch). Red List coverage overrepresents woody perennials and useful plants, but underrepresents single‐country endemics. Fungal assessments overrepresent well‐known species and are too few to infer global status or trends. Proportions of assessed vascular plant species considered threatened vary between global assessment datasets: 37% (ThreatSearch), and 44% (International Union for Conservation of Nature Red List of Threatened Species). Our predictions, correcting for several quantifiable biases, suggest that 39% of all vascular plant species are threatened with extinction. However, other biases remain unquantified, and may affect our estimate. Preliminary trend data show plants moving toward extinction. Quantitative estimates based on plant extinction risk assessments may understate likely biodiversity loss: they do not fully capture the impacts of climate change, slow‐acting threats, or clustering of extinction risk, which could amplify loss of evolutionary potential. The importance of extinction risk estimation to support existing and emerging conservation initiatives is likely to grow as threats to biodiversity intensify. This necessitates urgent and strategic expansion of efforts toward comprehensive and ongoing assessment of plant and fungal extinction risk. [ABSTRACT FROM AUTHOR]

Background: Tropical orchids need more study with respect to their mycorrhizal associations. For researchers in distant countries who aspire to study these orchids augmenting their conservation, the great distances involved, coupled with limited funds, pose formidable challenges. These challenges are sometimes exacerbated by political unrest, delays in securing permits, unexpected hardships, and the risk that the biological samples collected (e.g., roots harboring mycorrhizal fungi) will not survive long-distance transport. Results: We describe a protocol for the collection and transport of root samples from Madagascar orchids to labs in the United Kingdom (Kew) and the United States (Illinois) where Rhizoctonia-like fungi were subsequently isolated. Three separate trips were made spanning 4 years (2012-2015), with emphasis on the collection of roots from epiphytic, lithophytic, and terrestrial orchids inhabiting the Itremo Massif of the Central Highlands. Collectively, the trips to Madagascar resulted in the isolation of all major groups of Rhizoctonia-like fungi ( Ceratobasidium, Tulasnella, Sebacina) from all three orchid growth forms (terrestrials, epiphytes and lithophytes). Sampling of terrestrial and epiphytes during the rainy season (January) yielded best results. Conclusions: Our study demonstrates that peloton-forming fungi in root samples can retain viability up to 3 weeks after collection. [ABSTRACT FROM AUTHOR]

About 90% of Cynorkis species are endemic to the biodiversity hotspot of Madagascar. This terrestrial habitat-specific genus received little study for fungal diversity to support conservation. We evaluated the diversity of culturable fungi of 11 species and soil characteristics from six sites spanning a >40 km radius in and along the region's inselbergs. Peloton-forming fungi were grown in vitro from root/protocorm slices and positively identified using DNA sequencing. The fungal diversity was then correlated with soil pH, NO3-N, P, and K. All species harbored either putative mycorrhizal associates in the Rhizoctonia complex or Hypocreales fungi. Tulasnella Operational Taxonomic Units (OTUs) were most prevalent in all soil types while Serendipita OTUs were found in species inhabiting granite/rock outcrops in moist soil (seepage areas). Most Cynorkis species were present in soil with low NO3-N and P levels with diversity of mycorrhizal fungi inversely correlated to NO3-N levels. Of the different orchid life stages sampled, only one species (Cynorkis fastigiata) yielded putative mycorrhizal fungi from juvenile stages. As diversity of mycorrhizal fungi of Cynorkis spp. was negatively correlated with NO3-N, and majority of the studied taxa were found in soils with low NO3-N and P contents, reintroduction studies must include analysis of N and P in detail. For the first time, we showed that the assemblage of culturable fungi in the roots of habitat-specific species of Cynorkis (Orchidaceae) are intimately tied to specific soil characteristics. [ABSTRACT FROM AUTHOR]

The article focuses on the conservation of palms horticulture in Itremo, Madagascar. It states that there are only three species of local palm flora are recorded in the protected areas of Itremo including the Dypsis ambositrae, Dypsis baronii, and Dypsis decipiens. It mentions that Dypsis decipiens inhabits humid rocky sites throughout the forest margins.

The inselbergs of the Central Highlands of Madagascar are one of many 'micro-hotspots' of biodiversity on the island, particularly for Orchidaceae. In this region are several genera that have a large number of endemic species that are in serious decline or edging towards extinction. Studies relating to diversity of orchids and their fungal partners (both mycorrhizal and non-mycorrhizal root associates) deserve more attention, as climate change and human induced decline in resilience of species in the wild is at an all-time high. Identification of mycorrhizal fungi (MF) via conventional seed baited-protocorms has limitations for large scale studies and its application for time-bound conservation projects. The paper describes the value of understanding fungal diversity in the roots of orchids at different stages of maturity. The first part of the study was a preliminary investigation mainly to identify culturable Rhizoctonia endophytes, and the second part looked at all life forms of available taxa together with associated soil characteristics. We isolated and identified 19 putative MF from 18 of the 50 taxa spread over an area of 250 sq. km, covering three life forms, growth phases of the orchid taxa, and habitat types. In the rest of the taxa, we were unable to detect any putative MF, but had varying numbers of non-mycorrhizal endophytes. We also found that diversity of putative MF was higher in plants from soils with the lowest P levels recorded. Putative mycorrhizal OTUs were predominantly from the Tulasnella lineage, followed by Ceratobasidium and Serendipita. Within a small subset of samples, a difference in colonised endophytes depending on the collection season was observed. In vitro germination studies using 10 OTUs of mycorrhizal fungi in 14 orchid species showed mostly generalist associations. When orchid seed and fungal sources were studied irrespective of habitat, life form, and distance from each other (orchid seed and fungal source), compatibility for symbiotic seed germination was observed in most cases. Issues with the identification of compatible MF and symbiotic system of seed germination are discussed. [ABSTRACT FROM AUTHOR]

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.

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 the most 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.

Background: The need to incorporate genetic data into conservation management decisions is increasingly recognised. However, many published studies represent a 'gold standard' of sampling, techniques, and analyses. Such rigour is often not possible with limited funding and resourcing available for developing plans for the increasing number of threatened species requiring conservation management. Two endemic palm species of the Itremo Massif in central Madagascar, Dypsis ambositrae and D. decipiens , are known to be threatened with extinction and conservation management for these species is a priority for the newly created protected area in the region., Methods: The genetic diversity of these two species was studied using the relatively low-cost and rapid AFLP technique. DNA fragments generated using three primer combinations were analysed for 20 and 50 individuals of the two species, respectively, from across their ranges., Results: Genetic diversity was relatively low for both species. The two sites where the highly restricted D. ambositrae grows were found to be genetically distinct (although overall heterozygosity was low). Despite having a much wider distribution and relatively large population, D. decipiens did not show clear geographical nor genetic groupings and had similarly low genetic heterozygosity to D. ambositrae ., Discussion and Recommendations: With so few individuals remaining in the wild and two genetically distinct subpopulations, it is recommended that both sites of D. ambositrae are conserved and that seed are collected from both for ex situ conservation and potential future reintroduction. It may be less important to focus resources on conserving or collecting ex situ material from all sites where D. decipiens is found, as the genetic diversity represented by each subpopulation is limited and increasing sampling may not protect significantly higher levels of genetic diversity. This study provides data that inform and support conservation decisions taken for both species within this region, and in the management of the newly designated Itremo Massif Protected Area, which covers most of the sites where these two species remain in the wild., Competing Interests: The authors declare there are no competing interests.