A colourful world with a dark future: Unregulated trade as an emerging threat for woodlice (Isopoda: Oniscidea) of Spain

1. Woodlice (Isopoda: Oniscidea) constitute a diverse and ecologically significant group inhabiting a great variety of ecosystems with a crucial role for ecosystem functioning, but strongly overlooked in conservation efforts and threats to species and populations are hardly studied. 2. In this study, we evaluate for the first time the potential impact of an emerging unregulated trade on the woodlice of Spain. 3. We conducted a search for all Spanish species nationally and internationally traded via online shops and studied various aspects of the nature of this market and its tendency. 4. We found 56 species currently traded in international stores, and an additional 30 species through transactions on social media. Furthermore, the amount and number of species are increasing and far from stabilising, with higher prices paid for endemic than non-endemic species. 5. This situation puts pressure on local populations, potentially inducing local extinctions, affecting ecosystem functioning. 6. Other potential future threats such as genetic contamination of native populations and the introduction of alien species cannot be ruled out. 7. The conservation of woodlice faces significant challenges due to a lack of assessments of species conservation status and conservation action plans for the most affected species. 8. We propose preventive measures, such as the creation of whitelists or blacklists, essential to protect (endemic) species and mitigate the threat of invasive species.

We want to thank Adrià Miralles, Alejandro Pérez-Ferrer, Faluke, Sergio Monteagud, Pedro Lázaro Molinero and Petra Peuker for granting permits to use their photos of woodlice, anto Jorge Rodríguez-Pérez for his help with the composition and edition of Figure 1. We want to express our gratitude to Irene Matarredona for carrying out the illustration of the Graphical Abstract. Finally, we want to thank Pedro Cardoso and an anonymous reviewer for their constructive comments and suggestions. JR and ROR were supported by the University Teacher Training (FPU) program (FPU19/06456 and FPU21/02585, respectively) funded by the Ministry of Universities (Spain). We acknowledge support of the publication fee by the CSIC Open Access Publication Support Initiative through its Unit of Information Resources for Research (URICI).

Peer reviewed