Conservation of genetic diversity in Mediterranean endemic species: Arenaria balearica (Caryophyllaceae)

Abstract

Background – Biodiversity loss is a problem that needs to be urgently addressed, particularly with the uncertainties of climate change. Current conservation policies principally focus on endangered species but they often give little consideration to the evolutionary processes, genetic diversity, or the rarity of nonendangered species. Endemic species occurring in rocky habitats that are undergoing exceptional habitat loss appear to be one of the most important candidates for conservation. The aim is to establish in situ and ex situ conservation recommendations for the Mediterranean endemic species Arenaria balearica. Material and methods – Arenaria balearica is a species endemic to the Mediterranean with a disjunct distribution range throughout Majorca, Corsica, Sardinia, and other small Tyrrhenian islands. A combination of molecular techniques (AFLPs and plastid DNA) was employed to determine genetic diversity and rarity across populations and to calculate the Relevant Genetic Units for Conservation (RGUCs). Moreover, Species Distribution Models (SDMs) were developed to assess the potential current distribution and the expected situation under future climatic scenarios. Key results – To preserve the genetic diversity and rarity of the species, in situ conservation is proposed for six populations as RGUCs. Moreover, as the RGUCs can only account for a part of the phylogeographic signal, ex situ conservation is also suggested for some additional populations. According to the results, the habitat suitability in the 2050 scenario is limited and suitable areas for A. balearica could have disappeared by 2070. Therefore, the persistence of the species could be in danger in a short period of time and conservation planning becomes necessary.