The reproductive strategy of the gregarious endo-parasitoid Asecodes hispinarum (Hymenoptera: Eulophidae)

The Asecodes hispinarum (Hymenoptera: Eulophidae) is gregarious endo-parasitoid of Brontispa longissima(Gestro) (Coleoptera: Hispidae) which feeds on young leaflets of coconut palm and other palms. This parasitoid is pro-ovigenic and adults given only water survived for only 1-2 days. To elucidate the reproductive strategy of this parasitoid, we examined the host stage acceptance, host stage preference, host stage suitability including development time, survival, size of emerging adults. Although A. hispinarum females given only a host larva of different instars or pupa of different ages accepted all instars of larvae and 0-d to 3-d-old pupae, the percentages of acceptance for second to fourth instar larvae were significantly higher than that for the first instar or pupal stages. In multiple choice among first to fourth instars, most of females oviposited in only one or two hosts and preferred to oviposit in second to fourth instars. That a significant liner relationship between host size and the number of eggs per host suggests that the parasitoids roughly adjust the number of eggs based on the host size. Considering the facts that A. hispinarum has short adult longevity with a narrow range of hosts that are concealed in palm buds, this parasitoid would be time-limited, and may have developed a reproductive strategy to use a wide range of host stages efficiently in limited time.