Leg ornamentation and the efficacy of courtship display in four species ofwolf spider (Araneae : Lycosidae)

This study used both correlative and experimental video playback methods to test the hypothesis that the secondary sexual traits of male wolf spiders act to increase the efficacy of visual courtship displays. Direct observati ons of courtship of several lycosid genera and a review of the literature r evealed a significant association between ornamentation and visual courtshi p displays. This suggests that the ornamentation may be playing the role of amplifier for a visual display. To test this hypothesis, male courtship be haviors of four Schizocosa species were experimentally manipulated using vi deo-imaging techniques. Females of species with non-visually displaying, no n-ornamented males (Schizocosa duplex and S. uetzi) did not increase in fre quency of receptivity when tufts were added to conspecific males. In a spec ies with a visual display and foreleg pigmentation (S. stridulans), the add ition of foreleg tufts increased female receptivity. In a tufted species (S . crassipes), females tended to decrease their receptivity when male orname ntation was completely removed. In visually displaying species, ornamentati on acts to increase female receptivity, supporting its role as an amplifier of a visual display.