TEMPORAL ASPECTS OF SPERM TRANSFER AND SPERMATOPHORE CONDITION IN MEXICAN RICE BORERS (LEPIDOPTERA, PYRALIDAE)

Sperm transfer and spermatophore disintegration in females and duplex refilling in males of the Mexican rice borer, Eoreuma loftini (Dyar), were examined by freezing moths at time intervals after mating. Eupyre ne sperm location and spermatophore condition in female moths changed with time after mating. Sperm transferred from the spermatophore to th e spermatheca between 6 and 8 h after mating. Spermatophores passed th rough several stages of disintegration and were completely disintegrat ed after 72 to 96 h. Stages of spermatophore disintegration are descri bed and can be used to estimate time since females have mated. Numbers of sperm bundles in male duplexes increased with increasing time afte r mating but were too variable to be of practical use in assessing mat ing status. The best indicator of male mating status was duplex condit ion (color). Duplex condition can be used to determine mating status f or almost-equal-to 6 h after mating, although estimates using this cri terion will be slight underestimates of actual mating activity.