Conservation status of three endemic plants of the Selvagens Islands (Northern Atlantic Ocean): Argyranthemum thalassophilum, Asparagus nesiotes subsp. nesiotes and Euphorbia anachoreta

Abstract

Argyranthemum thalassophilum, Asparagus nesiotes subsp. nesiotes and Euphorbia anachoreta are three threatened taxa that are endemic to the Selvagens Islands, a very isolated archipelago of small islands in the Atlantic Ocean. As a part of a conservation project for the three taxa, we conducted fieldwork that included detailed censuses and identification of threatening factors, which ultimately allowed the assessment of their IUCN Red List status. The three species should be categorized as Endangered under the criterion D, as for all the cases there are fewer than 250 mature individuals (79, 119, and 58 for Argyranthemum thalassophilum, Asparagus nesiotes subsp. nesiotes and Euphorbia anachoreta, respectively). In spite of the fact that A. thalassophilum does not show the lowest census size, this taxon should be regarded as the most threatened because it is the only one showing no regeneration (i.e. a total lack of seedings and/or juveniles).

Keywords:

• Argyranthemum thalassophilum
• Asparagus nesiotes subsp. nesiotes
• conservation
• endangered
• Euphorbia anachoreta
• Selvagens Islands

Acknowledgements

We thank the wardens José Isamberto Gomes da Silva and Manuel Lourenço Gomes Alves (Serviço do Parque Natural da Madeira) for their cooperation, logistical support during our stay in Selvagem Pequena, the wardens Paulo Moniz and Carlos Santos (Serviço do Parque Natural da Madeira) for making the census of Euphorbia anachoreta, and Carolina Jardim Santos (Jardim Botânico da Madeira) for her help in obtaining permission to work on the Selvagens Islands. We also thank the Portuguese Navy (Comando da Zona Maritima da Madeira) for transporting us to the islands. RV and JL-P are in the “Plant Biodiversity and Biosystematics” group of Generalitat de Catalunya (Ajuts a Grups de Recerca Consolidats 2014-SGR514-GREB and 2017-SGR1116).

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by project no. 10251651 granted by The Mohammed bin Zayed Species Conservation Fund.