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We review the conservation status and threats to the endemic vascular flora of the Cape Verde islands, mostly based on the past two decades of collecting, literature review and herbarium specimens. The application of IUCN Red List criteria and categories using RAMAS software reveals that 78% of the endemic plants are threatened (29.3% Critically Endangered, 41.3% Endangered, 7.6% Vulnerable). Most of these endemics have a limited geographical range, and half of them have Areas of Occupancy and Extents of Occurrence of < 20 and 200 km 2 , respectively. Our data show that, over the last two decades, the Cape Verde vascular plants have become more threatened and their conservation status has declined, mostly as a consequence of the increase in exotic species, habitat degradation and human disturbance. This paper presents the first comprehensive IUCN Red List data review for the plants endemic to Cape Verde, thus providing an important step towards the recognition and conservation of its threatened endemic flora at the national and global level. It also fills a knowledge gap, as it represents the first thorough assessment of the conservation status of the entire endemic flora of a Macaronesian archipelago.

With climate change, drought is expected to increase, and its negative impacts will be particularly important in developing countries, usually with rainfall-dependent agriculture. The Cabo Verde archipelago is characterized by limited resources, remoteness, vulnerability to natural disasters, and a fragile environment. In this study, we provide the first report of the current status and trends of agriculture in Cabo Verde. We present data on the current performance of agricultural production areas in these islands and discuss them in terms of their most important natural constraint, water. Also, we assess the impact of institutional strategies on crop production and evaluate recent mechanisms that have been engaged towards agrarian development in this archipelago. Our results show that, among the ten Cabo Verde Islands, Santiago has the largest area used for agriculture (52.5%), followed by Santo Antão (16%) and Fogo (15.8%), and that rainfed farming dominates in all of them. The staple crops, such as maize and beans, are produced through rainfed subsistence farming, whereas irrigated crops (i.e., sugarcane, tomatoes) are mostly grown for commercial purposes. The prolonged drought periods, exposure, erosion and soil degradation, which led to increasing desertification over the last decades, have been identified as the main constraints to agrarian development across the ten islands of the archipelago. The strategies of Cabo Verde government to mitigate water scarcity through small-scale irrigation based mainly on small dams and drip irrigation technology have a marked effect on agricultural production in the predominantly arid and semi-arid areas of this archipelago.

The flora and vegetation of the archipelago of Cabo Verde is dominated by Macaronesian, Mediterranean, and particularly by African tropical elements, resulting from its southernmost location, when compared to the other islands of the Macaronesia (i.e., Azores, Madeira, Selvagens, and Canary Islands). Very likely, such a geographical position entailed higher susceptibility to extreme climatic fluctuations, namely those associated with the West African Monsoon oscillations. These fluctuations led to a continuous aridification, which is a clear trend shown by most recent studies based on continental shelf cores. Promoting important environmental shifts, such climatic fluctuations are accepted as determinant to explain the current spatial distribution patterns of taxa, as well as the composition of the plant communities. In this paper, we present a comprehensive characterization of the main plant communities in Cabo Verde, and we discuss the role of the climatic and topoclimatic diversity in shaping the vegetation composition and distribution of this archipelago. Our study reveals a strong variation in the diversity of plant communities across elevation gradients and distinct patterns of richness among plant communities. Moreover, we present an overview of the biogeographical relationships of the Cabo Verde flora and vegetation with the other Macaronesian Islands and northwestern Africa. We discuss how the distribution of plant communities and genetic patterns found among most of the endemic lineages can be related to Africa’s ongoing aridification, exploring the impacts of a process that marks northern Africa from the Late Miocene until the present.

Cabo Verde’s biodiversity is threatened by activities that meet human needs. To counteract this, an integration of scientific and indigenous knowledge is required, but no comprehensive list of the useful local plants is available. Thus, in this work, we assess (1) their diversity and phytogeography; (2) the role of geophysical, historical, and socio-economic factors on species distribution and uses; and (3) potentially relevant species for sustainable development. Data were obtained from flora, scientific publications, historical documents, herbarium specimens and field work. Many species were introduced since the 15th century to support settlement and commercial interests. We identified 518 useful taxa, of which 145 are native, 38 endemic and 44 endangered. The number of useful taxa is correlated with altitude and agricultural area, as well as with rural population indicators, but not with total population or socio-economic indicators such as gross domestic product. Native taxa are mostly used for fuelwood, forage and utilitarian purposes. Agrobiodiversity and traditional practices seem crucial to cope with recurrent droughts and ensure food security. Most of the introduced species do not present conservation problems, contrasting with the overuse of some native taxa. The safeguarding of native populations will ensure the sustainable exploitation of these resources and benefit the local economy.

The genus Sideroxylon is revised for the Canary, Cape Verde and Madeira archipelagoes. Three species are recognized: S. mirmulans which is endemic to Madeira and adjacent islets and which is the valid name for the species usually known as S. marmulano; S. canariense spec. nov. from the Canary Islands is described as new to science; S. marginata from the Cape Verde Islands has formerly been regarded as synonym or as a variety of S. marmulano and is now recognized as a separate species. A key for identification, descriptions, illustrations, distribution maps and data on the ecology of the species are given.

Tornabenea is a small Apiaceae genus that is endemic to the Cape Verde Islands. Its species differentiation is based just on a few macromorphological characters: leaf shape, number and shape of umbel bracts and mericarp ribs. These characters vary within each species and show high plasticity. Thus, in recent taxonomic data of the genus, there are different viewpoints as to the number of species. Here, in order to improve the taxonomy of the genus, microcharacters of the vegetative and reproductive structures of three taxa-T. insularis, T. annua and T. tenuissima-have been examined. The shape and arrangement of hairs on the surface of the mericarps, and the presence and structure of starch grains are the only different microcharacters noted in T. insularis and T. annua. Chromosome number of the latter two species is 2n ¼ 18. Our preliminary results disagree with the existing classifications of the genus Tornabenea. In fact, they do not lead to a clear separation between T. insularis and T. annua. By contrast, it is easy to distinguish between these species and T. tenuissima, which possesses more peculiar microcharacters.

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