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- Population decline in the critically endangered Musschia isambertoi (Campanulaceae) endemic to Desertas Islands (Madeira Archipelago) calls for urgent conservation managementPublication . Sequeira, M. Menezes de; Jardim, R.; Gouveia, M.; Góis-Marques, C. A.; Eddie, W. M. M.Macaronesian islands display a high degree of plant endemicity and correspond to some of the most threatened biodiversity hotspots due to several human driven impacts such as habitat loss, invasive species, overexploitation or climate change. The conservation status of the largest of the two known population of Musschia isambertoi M. Seq., R. Jardim, Magda Silva and L. Carvalho (Campanulaceae) was assessed recently. Field work was done in June 2018 in “Porto das Moças” Deserta Grande (Madeira Archipelago, Portugal), the locus typicus, where in 2006 close to 30 plants were detected with a high variation of age/size between individuals comprising both fully flowering and non-flowering adult plants as well as seedlings, and thus corresponding to a healthy population. This study assesses population size, age and plant size, and genetic, as well as floristic diversity. The total area of the site corresponds to approximately 1500 square meters. Ten individuals were detected, all corresponding to young seedlings not exceeding 15 cm high, and exhibiting approximately the same size and numbers of leaves (4–8). No adult plants or remains of adult plants were seen. Ecological data and direct herbivory evidence suggest that perennial plants are subjected to elimination during the short summer by the feral goat population. Mo lecular data based on ISSR markers show that the nine sampled individuals (out of ten individuals found) are genetically identical, possibly resulting from one parental plant. Results clearly suggest that Musschia isambertoi is very close to extinction. Urgent conservation measures are imperative and should include the immediate fencing of the population followed by the elimination of feral goats from Deserta Grande. The elimination of feral goats was initiated in 1996 (LIFE95 NAT/P/000125, 383,467.00 €) but stopped due to inappropriate conser vation policies of the former Services of the Natural Park of Madeira.
- The Madeiran laurel forest endemic Goodyera macrophylla (Orchidaceae) is related to American orchidsPublication . Thiv, Mike; Gouveia, Manuela; Sequeira, Miguel Menezes deMacaronesian laurel forests harbour many herbs and lauro phyllous trees with Mediterranean/European or Macaronesian affini ties. Traditionally, the origin of these taxa has been explained by the relict hypothesis interpreting these taxa as relics of formerly wide spread laurel forests in the European continent and the Mediterranean. We analysed the phylogenetic relationships of the Madeiran laurel forest endemic Goodyera macrophylla (Orchidaceae) using sequences from the nuclear ribosomal DNA Internal Transcribed Spacers (ITS) and plastid DNA regions. The results were incongruent, either the two Central American G. brachyceras and G. striata (ITS) or the North American G. oblongifolia (plastid DNA) were sister group to G. mac rophylla. Nonetheless, biogeographic analyses indicated an American origin of this nemoral laurel forest plant in the two data sets. Molecu lar clock analyses suggest a colonisation of Madeira in the span of the upper Miocene/lower Pliocene to the Pleistocene. Although the relict hypothesis cannot be ruled out by our data when assuming extinction events on the European and northern African mainland, dispersal from Central or North America to the archipelago of Madeira is a much more likely explanation of the data.
- Contribution to the flora of the Selvagens archipelago (Portugal) (I)Publication . Sequeira, Miguel Pinto da Silva Menezes de; Góis-Marques, Carlos; Gouveia, Manuela; Zino, Francis; Bairos, Célia; Mesquita, Sandra; Capelo, JorgePlant specimens obtained by the authors from several expeditions to the Selvagens Islands (2004-2021), complemented by the study of herbarium specimens, led to the identification of several new species records for the Selvagens archipelago, namely the taxa currently considered as Canary Islands endemics Trisetaria lapalmae and Polycarpaea divaricata. Other new taxa records for the Selvagens Islands include Convolvulus siculus subsp. elongatus and the grasses Bromus rigidus and Phalaris minor. Notes on Misopates salvagense, Asplenium marinum, Spergularia diandra and Rostraria pumila are also included. Comments on taxa include distribution, ecology, taxonomy, nomenclature, conservation, and historical data. Results are discussed in the light of habitat restoration, following Nicotiana glauca near eradication and rodent eradication. These aspects are also discussed considering the historical evolution of knowledge on the Selvagens vascular flora.