The Atlantic connection: coastal habitat favoured long distance dispersal and colonization of Azores and Madeira by Dysdera spiders (Araneae: Dysderidae)

Abstract

The woodlouse hunter Dysdera spiders have colonized all Macaronesian archipelagos. We report here for the first time an evolutionary connection between the Iberian Peninsula, Madeira, and the remote archipelago of Azores. Based on museum specimens from the 1950s, we describe the first endemic Dysdera species from the Azores. Additionally, we report the recent collection of immature individuals related yet probably not conspecific to the new species, rejecting previous suggestions that the endemic lineage had gone extinct. A multi-locus target phylogeny revealed that an undescribed species from Madeira was the closest relative to the Azores lineage, and that both island taxa were in turn sister to an Iberian endemic species, within a mostly Iberian clade. Interestingly, the Madeiran relative was not closely related to the remaining endemic species reported in the archipelago, suggesting an independent colonization. A divergence time estimation analysis unravelled that Dysdera colonized both archipelagos early after their emergence. The colonization pathway remains ambiguous, but the Iberian Peninsula acted as the ultimate source of the ancestral colonizers. Finally, we describe the new species Dysdera cetophonorum Crespo & Arnedo sp. nov. from Pico and Dysdera citauca Crespo & Arnedo, sp. nov. from Ilhéu de Cima (Porto Santo) and redescribe and illustrate the female genitalia for the first time of their poorly known closest relative, Dysdera flavitarsis Simon, 1882 from the north-western Iberian Peninsula.

http://zoobank.org/urn:lsid:zoobank.org:pub:1E75CCEC-1632-4581-93A5-E61721970022

Key words:

• colonization
• divergence time
• endemism
• long distance dispersal
• Macaronesia
• systematics

Acknowledgements

We would like to thank Paulo Borges for arranging the logistic setup of the trip to the Azores to search for D. cetophonorum sp. nov. Our thanks are also due to the IFCN of the Madeira Regional Secretariat of Environment, Natural Resources and Climate Change for coordinating the logistical arrangements, and for providing collection and transport permits, namely to C. Santos and D. Menezes. The museum curators who loaned materials and those who facilitated storage of the type series of the new species are hereby acknowledged: J. Beccaloni (BMNH), B. Caballero (MZB) and Y. Gonçalves (MMF). Original distribution maps from Madeira and Azores were provided under copyright agreement by DROTA and project CLIMAAT, respectively, coordinated by Eduardo Brito de Azevedo. We are in debt with H. D. Cameron for the etymology of the new species from the Azores. Live photo of D. citauca sp. nov. was provided courtesy of Emídio Machado. We thank Ivan Magalhaes and one anonymous reviewer for helpful comments that greatly contributed to improve the manuscript.

Disclosure statement

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

Supplemental material

Supplemental material for this article can be accessed here: https://doi.org/doi/10.1080/10.1080/14772000.2021.1946618.

Associate Editor: Rosa Fernandez

Additional information

Funding

L.C. was funded by an individual PhD grant SFRH/BD/110280/2015 from Foundation for Science and Technology (FCT, Portugal). This work was supported by project CGL2016-80651-P from the Spanish Ministry of Economy and Competitivity (M.A.). Additional funds were provided by the project 2017SGR83 from the Catalan Government (M.A.).