Hiding in plain sight: Microhabitat selection by the trunk-dwelling spider Ypypuera crucifera (Araneae, Hersiliidae), with notes on its natural history

Habitat selection provides biological advantages, including benefits for foraging, reproduction, and predator avoidance. Abiotic factors like vegetation and substrate characteristics play a critical role in this process. This study examined the microhabitat selection of the two-tailed trunk-dwelling spider Ypypuera crucifera in semideciduous dry tropical forests. Rough, circular tree trunks were preferred, likely aiding escape behaviors and reducing predation risk, while smooth or concave trunks were avoided. Spider abundance peaked at mid-height positions (100–160 cm), aligning with predator avoidance strategies. Contrary to expectations, lichen coverage did not influence occupancy, despite its potential role in camouflage for Y. crucifera. Observations revealed reproductive behaviors, including guarded, trunk-attached egg sacs. These findings enhance understanding of Y. crucifera's habitat preferences and natural history, highlighting the importance of tree trunk characteristics in shaping its ecology.