Habitat use and ecological traits of the orb-weaving spider Argiope lobata (Pallas, 1772) (Araneae: Araneidae) in Iberian dehesas

Spiders are dominant terrestrial predators that shape arthropod communities. Among them, orb-weavers are especially informative because their orb webs act both as prey-capture devices and as sensory interfaces with the environment, allowing behaviour to be inferred from web architecture. Despite extensive work on Argiope spp. Audouin, 1827, the ecology of Argiope lobata (Pallas, 1772) remains poorly documented, especially in mainland Iberian Peninsula. We studied the web and foraging ecology of A. lobata in an Iberian dehesa across two contrasting seasons (2019–2020). We quantified web traits, substrate use and prey composition from 317 occupied webs. We found that several traits differed between years, indicating context-dependent responses. Web architecture reflected the space provided by available supports, consistent with flexible placement across vegetation types. Web orientation was non-random (overall north-east) and shifted subtly between years. Stabilimenta were frequent (∼76%), typically simple, and their occurrence increased with web size and height. Hymenoptera dominated prey in both years, and dietary niche breadth was moderately narrow and similar between years. Together, these results provide the first mainland data for A. lobata ecology in the Iberian Peninsula and document context-dependent variation in web building.