Fig. 3. Progress of spermatophore melanization in 7^* representative L. vannamei males that were followed throughout 32 weeks, including a male-only period of 9 weeks (weeks 24-32). The light-gray rectangle that covers the histogram in the area between weeks 5-15 represents the period of time in which the females were vitellogenically active. In week 5, one of the seven males was found slightly melanized and then `white' again on week 6. Then, three males developed melanization between weeks 7-10 but all of them recovered and were found `white' between weeks 12-14. All the recoveries occurred strictly during the period in which the females were vitellogenically active (weeks 5-15). ^*Only 6 males remained at week 26 and only 5 at week 29.