Male-made abdominal marks as an indicator of female mating status in noctuid species

In certain moth species, scales from ventral surface of the female abdomina l tip may be removed by the male valvae during mating. The occurrence and f requency of these scaleless patches or "abdominal marks" were quantified in an array of noctuid species to determine if these could be used as a non-i ntrusive means of determining the mating status of females. In 20 species, abdominal marks were never found on mated females despite the large sample sizes examined. In another 15 species the percentage of mated females (dete rmined. by the presence of spermatophores) with abdominal marks was suite v ariable, ranging from 1 to 100%. In three species, >95% of mated females bo re abdominal marks: Aporophyla nigra Haworth, Hecatera bicolorata Hufnagel, and Mythimna unipuncta Haworth. In most species the frequency of marking w as related to multiple mating (polyandry). Marks were also observed on some virgin females, i.e., individuals with no spermatophore. It is concluded t hat the presence of these scale-less patches may only provide a reasonable indication of the female mating status for certain species.