Lycosid Spiders on Artificial Foliage: Straum Choice, Orientation Prefrences, and Prey-Wrapping

The majority of lycosid spiders neither spin webs for prey capture nor hunt actively, but spend most of their time waiting for prey at a resting site (Cragg, 1961; Edgar, 1969). In this regard, those lycosids that inhabit the herbaceous stratum resemble the aerial web-weaving spiders. As does a web, the foliage substratum provides a waiting site, a medium for transmission of vibratory stimuli produced by prey, and a surface on which capture is performed (Rovner and Knost, 1974). In the present study we used artificial foliage to examine stratum choice in Lycosa punctulata Hentz and L. rabida Walckenaer, which usually are found in the herbaceous stratum of fields, and in Schizocosa saltatrix (Hentz) and S. crassipes (Walckenaer), which typically are found on the leaf litter of forest floors. We also studied body orientation preferences shown by individuals of the first three species when they rested at an elevated site on the artificial foliage. The significance of a preference for vertical orientation was hypothesized with regards to equalizing proprioceptive input, minimizing energy expenditure, facilitating prey detection, and improving concealment from predators. Finally, we observed post-immobilization prey-wrapping to determine if this behavior is an adaptation for retention of captured prey by spiders dwelling in the herbaceous stratum, as hypothesized by Rovner and Knost (1974).