Fig. 6. Periodic disappearance of spermatophores in L. vannamei males related to the molt cycle. (A-C) The spermatophore disappearance phenomenon in a representative male shrimp. Above the photographs is a colour-coded diagram; the white circles indicate the presence of spermatophores in the ampoules; the green circle, empty ampoules without spermatophores; and the yellow triangle, the molt event (ecdysis). In all three pictures, the ampoules are marked with broken arrows. (A) Intermolt with intact spermatophores. Solid arrows indicate the genital papillae that house the sexual openings. (B) 12 h before ecdysis in latepremolt; the ampoules are empty but are visible as two lumps underneath the cuticle. (C) 36 h post molt; a new pair of spermatophores can be seen through the cuticle. The lower part of the figure shows three representative individual male time tracks, which are color coded as described above. Each of these time tracks describes five observed molt events that cover four complete molt cycles in which the spermatophore disappearance phenomenon was observed. Two missed observations, for which we did not manage to observe the ampoules before the animal molted, are also indicated. Nevertheless, in both cases the animal molted on the same night.