Developmental biology of the coconut black-headed caterpillar, Opisina arenosella (Walker) (Lepidoptera: Xyloryctidae)

The coconut black-headed caterpillar, Opisina arenosella (Walker) (Lepidoptera: Xyloryctidae) has been one of the most serious defoliators of coconut plants in Vietnam. This study was carried out at the Entomology Laboratory, Faculty of Agronomy, Nong Lam University, Vietnam during 2020-21 to determine some biological characteristics of O. arenosella at a constant temperature of 28oC and a photoperiod of 12L : 12D. It was concluded from this study that the total developmental time from egg to adult emergence of O. arenosella was 57.7 days for female and 52.6 days for male. The eggs hatched in 6.1 days after oviposition. The duration of the larval period was 41.2 days. The pupal development lasted for an average of 3.6 days. The females produced a mean of 278.8 eggs during an average lifespan of 4.9 days. The longevity of the female (4.9 days) was shorter than that of the male (10.7 days). The knowledge of the basic biological characteristics of this caterpillar is of fundamental importance for facilitating improved timing of application of control measures and mass-rearing techniques for O. arenosella to supply insect hosts to mass-rearing of its parasitoids.