Environmental variables and distribution data support the preliminary conservation status of a trapdoor spider in a transformed coastal ecosystem

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Mediterranean coastal ecosystems are major tourist destinations that support intensive real estate business developments. However, these areas are also important as biodiversity hotspots. Coastal spiders have been poorly studied as indicators of habitat disturbance, especially those that depend on certain environmental variables. Plesiolena bonneti is a trapdoor spider that exclusively inhabits the coastal areas of central Chile (i. e., the Coquimbo region, 29°57′S, 71°20′W), intensely affected by habitat loss due to urbanization associated with tourist destinations. The main aim of this work was to establish, preliminary, the conservation status of P. bonneti supported by different environmental variables that define the activity period and occurrence of P. bonneti males and its distribution area. Trapdoor spiders are rare and difficult to observe in the field. and therefore, we used datasets obtained from citizen science to establish the period of activity, and environmental variables (maximum temperature, relative humidity, and month of observation) as predictors of its occurrence. Moreover, since it lives in an area perturbed by urbanization, we propose a preliminary conservation status using the IUCN Red List. We found that the species is observed significantly more in the austral autumn and that its occurrence (65 % of variability through Akaike weight) depends on maximum temperatures of 17 °C and relative humidity above 90 %. Its current distribution is mainly coastal, between the Atacama and Coquimbo regions. We propose that this species should be considered a vulnerable species. The increased observation of male P. bonneti post-rains may be driven by a physiological response to avoid water loss, which would coincide with the reproductive period. As the largest number of records are observed in coastal urban areas, we propose two simple management measures: the creation of nature reserves within the city, and an educational program for this spider.