AN ANALYSIS OF DISPLAY IN LYCOSID SPIDER LYCOSA RABIDA WALCKENAER

1. 1. Laboratory studies of visual and chemical communication involved in the pre-copulatory behaviour of Lycosa rabida were conducted during the summer and fall of 1963, 1964, and 1965. 2. 2. The male's courtship pattern consisted of an alternation of courtship sequences and intersequence intervals. During each courtship sequence the male performed a variable number of palpal rotations and a foreleg extension movement. There was a rapid alternation of the palps within each sequence and an alternation of the forelegs used in successive sequences. 3. 3. The regulation of the pattern of foreleg extensions was influenced by proprioceptive feedback. 4. 4. Responsiveness of females to palpless males indicated that the palpal rotation movements were not an essential component of courtship display. 5. 5. Receptive females performed leg waving displays during the inter-sequence intervals. The occurrence of the female's response during the male's motionless period probably increased the likelihood that the male would perceive the signals. 6. 6. In response to movements by the female, the frequency of courtship movements by the male increased. Pre-copulatory behaviour in this species involved reciprocal display. 7. 7. When the male was close enough to touch the female, he performed restricted foreleg extensions and thereby avoided contact. 8. 8. Males courted other males. However, once courtship was initiated by one male, the other male did not court, but performed a threat display. Apparently, males could recognize the sex of other males on the basis of courtship movements or sounds but not on the basis of form or colour alone. 9. 9. Synchronous leg spine erection was shown by males during contact with other males and apparently served as a defensive mechanism. 10. 10. Sex pheromone which released courtship display in males was produced by adult females. Pheromone release began about 2 weeks after the final moult and continued for at least one month thereafter. 11. 11. Courtship behaviour was not shown by penultimate males. Onset of the courtship tendency occurred about 4 to 5 days after the final moult. Males up to 4 months post-moult in age displayed courtship. 12. 12. 'Vacuum activity' shown by males seemed to be a response to sub-normal visual stimuli. © 1968.