A species living in an increasingly threatened habitat

To date, the species Dysdera curvisetae has only been identified in three very distant localities on the island of Tenerife but, according to researcher Sara Guirao, “its distribution may be more extensive”. Guirao, from the UB’s Department of Genetics, Microbiology and Statistics, explains that this species “belongs to the genus Dysdera, which is the genus of spiders with the highest species richness in the Canary Islands archipelago. It is a genus that has diversified greatly in the islands and more than fifty endemic species are known, that is, those that are exclusive to this archipelago”.

This species is found in the intertidal zone — a rare habitat for this genus of spiders — and has had to develop specific adaptations to survive in this coastal ecosystem. For years, this has been one of the most threatened habitats in the archipelago (urban development, pollution, overexploitation of the coastal area, etc.).

“For this reason, it would be important to assess the state of conservation and the threats suffered by the species that inhabit this increasingly reduced natural ecosystem”, Guirao points out.

Despite the importance and diversity of spiders in natural ecosystems, “little importance has been given to their conservation. In the Canary Islands there is no spider species included in the Canary Islands Catalogue of Protected Species and no species has yet been catalogued according to the criteria of the International Union for Conservation of Nature (IUCN)”, says Nuria Macías, from the ULL’s Department of Animal Biology, Soil and Geology. Recently, a project has been granted by the International Union for Conservation of Nature (IUCN) within the framework of the Atlantic Islands Invertebrate Specialist Group (AIIS) — in which researchers Nuria Macías and Carlos Zaragoza from the ULL participate — to evaluate thirty-six species of spiders from the Canary Islands, including the species Dysdera curvisetae.

A model for studying evolution in archipelagos

For years, the genus Dysdera has been the subject of study by research teams from the UB and the ULL, which have promoted several lines of genomic studies to understand the processes of colonization, diversification and speciation in the Canary Islands. With the ERGA-EBP project, which joins previous initiatives of the team to study various species of the genus Dysdera, it will be possible to generate the reference genome of the species D. curvisetae, “which allows us to study the genomic bases of adaptive convergence, an evolutionary process that explains how phylogenetically unrelated species can develop similar characteristics, due to adaptation to similar ecological niches”, explain Guirao and Macías.

The experts explain that they will be able to study this evolutionary process “in a new habitat uncommon among spiders of this genus and learn how these organisms adapt to an environment that is particularly vulnerable to anthropogenic effects and climate change”. “In parallel, the project will also help to understand the genomic consequences of island colonization”, they add.

The sequencing of the genome of Dysdera curvisetae will generate a new genomic resource that will be crucial to predict how factors such as coastal degradation and climate change may affect these organisms and to assess their adaptive potential to cope with all these changes. Julio Rozas, UB professor and member of the Bioinformatics Barcelona (BIB) platform, points out that “this resource allows us to develop effective strategies to improve the conservation of this species”. He adds: “This project will give visibility to this species and its entire ecosystem, and will also allow Dysdera curvisetae to act as an umbrella species for the conservation of the rest of the species that inhabit this coastal ecosystem”.

Goal: to protect Europe’s biodiversity

This initiative is one of the projects within the global action ERGA-BGE Enhancing Biodiversity Genomics Applications for Ongoing Case Studies, which aims to enhance collaboration between institutions to promote the production of reference genomes and expand the use of genomic data to protect biodiversity in the European framework.

In the ERGA-BGE project set, scientific teams from 33 countries will join forces to generate high-quality genomes that are benchmarks for biodiversity conservation or to determine how selected species contribute to the global improvement of the natural environment, health or the bioeconomy.