Alfonso Pita

A new multiplexed microsatellite tool for metapopulation studies in the overexploited endemic limpet Patella aspera (Röding, 1798)

Patellid limpets are ecologically important keystone grazers having a long history of overexploitation in the Macaronesian Archipelagos (NE Atlantic islands), where some species, such as Patella aspera, are under serious risk.[1, 2] Patella aspera is a protandric sequential hermaphrodite species with external fertilization, in which individuals start off as males but may undergo a sex reversal with age.[3] Hence, exploitation tends to focus on the larger females in the population as larger limpets (predominantly females) are selectively removed. Despite conservation legislation in Canaries, Madeira and Azores, limpets are under severe pressure and few individuals survive long enough to become females, a phenomenon that severely restricts the effective population size.[4] New conservation actions for the protection and sustainable use of limpets in Macaronesian Archipelagos are urgently needed and should be based on a multidisciplinary framework based on knowledge of the population dynamics and connectivity of this species.

Disentangling the genetic and morphological structure of Patella candei complex in Macaronesia (NE Atlantic)

Abstract The uptake of natural living resources for human consumption has triggered serious changes in the balance of ecosystems. In the archipelagos of Macaronesia (NE Atlantic), limpets have been extensively exploited probably since islands were first colonized. This has led to profound consequences in the dynamics of rocky shore communities. The Patella candei complex includes various subspecies of limpets that are ascribed to a particular archipelago and has been the focus of several taxonomic surveys without much agreement. Under a conservational perspective, we apply morphometric and genetic analyses to test subspecies boundaries in P. candei and to evaluate its current population connectivity throughout Macaronesia (Azores, Madeira, and Canaries). A highly significant genetic break between archipelagos following isolation by distance was detected (F ST = 0.369, p < .001). Contrastingly, significant genetic differentiation among islands (i.e., Azores) was absent possibly indicating ongoing gene flow via larval exchange between populations. Significant shell‐shape differences among archipelagos were also detected using both distance‐based and geometric morphometric analyses. Adaptive processes associated with niche differentiation and strong barriers to gene flow among archipelagos may be the mechanisms underlying P. candei diversification in Macaronesia. Under the very probable assumption that populations of P. candei from each archipelago are geographically and/or ecologically isolated populations, the various subspecies within the P. candei complex may be best thought of as true species using the denomination: P. candei in Selvagens, Patella gomesii in Azores, Patella ordinaria in Madeira, and Patella crenata for Canaries. This would be in agreement with stock delimitation and units of conservation of P. candei sensu latu along Macaronesia.