The effects of differential eye occlusion on prey and mate recognition in the brush-legged wolf spider Schizocosa ocreata (Hentz, 1844)

We examined the role of lycosid eye rows and the pairs of eyes within each row in prey detection and mate recognition by Schizocosa ocreata (Hentz, 1844) using two approaches: (1) occluding anterior or posterior eye rows; and (2) occluding all but a single eye pair. In response to live prey, females took longer to orient and approach crickets when the posterior eye row was occluded; responses were intermediate when the anterior eye row was occluded. With six of eight eyes occluded, spiders that could see with posterior lateral eyes (PLE-only) detected the cricket as quickly as the fully sighted spiders (controls), while spiders limited to seeing from other eye pairs took longer to orient towards prey. Orientation distance varied significantly as well, with Control, ALE-only, PME-only and PLE-only spiders responding at greater distances than AME-only spiders. To analyze the functions of the eye rows involved in mate preference in S. ocreata, we conducted an additional study with presentation of video playback of a courting male to females with different eye rows occluded. Females with their posterior eyes occluded took longer to orient and respond compared to controls and anterior eye row occlusion. The sum of female receptivity displays was also significantly reduced when posterior eyes were occluded, suggesting the posterior eyes may be involved in mate recognition. Taken together, these data suggest that the posterior (secondary) eyes may have an important role in detection and identification of both prey and courting males.