Potential role of foreleg trichobothria in the reception of air particle movement during wolf spider courtship

Spiders use information received from trichobothria for capturing prey or escaping predators. However, we have no extensive information on if or how trichobothria might be used in conspecific communication. This study tests the hypothesis that female wolf spiders Schizocosa retrorsa, (Banks, 1911) use their foreleg trichobothria to detect and assess courting males. Prior studies have shown that male S. retrorsa can mate successfully in signaling environments where females cannot detect visual or vibratory signals. Despite this, higher rates of male leg waving still predicted successful mating. In addition to their visual conspicuousness, these rapid leg waves can generate air particle movement that may be detectable by a female's trichobothria. If females use trichobothria to detect and assess male leg waving, then we might predict the following. When female trichobothria are compromised, we expect (i) lower overall mating success and (ii) no relationship between male mating success and leg waving rate. To test these predictions, we ran mating trials in environments unconducive to visual or vibratory signals and compared the mating success and mating predictors of female/ male S. retrorsa pairs across two female treatments groups: (a) foreleg trichobothria unablated and (b) ablated. We found no significant difference between the mating success of the two groups. However, mating success was higher for males that waved their legs at a faster rate in the unablated, but not the ablated treatment groups. Our results indicate that the ablation of female trichobothria interferes with the detection and assessment of male leg waving, supporting a role of trichobothria in receiving air particle movement signals.