Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide

Abstract

Latoia (Parasa) lepida (Cramer) Lepidoptera Limacodidae, a coconut pest in Indonesia.

Abstract

Latoia lepida (Cram.) is common in all south-western Asia, especially in Indonesia, attacking many different plants but showing a strong preference for coconut palm. Notes are given on its morphology, biology, parasitism, damage, economic threshold and control. The egg stage lasted 6 days, the larval stage 40 days and the pupal stage 22 days, but these periods varied greatly according to climatic conditions. Adult emergence always coincided with the onset of the rains. Despite the high fertility and gregariousness of the limacodid, its numbers were usually kept under control by an abundant complex of parasites, of which the most efficient were the braconid Apanteles parasae Rohw. and the tachinid Chaetexorista javana Br. & Berg., both of which attacked the older larvae; however, the late commencement of parasitism sometimes permitted severe damage to be caused by the young larvae, including complete defoliation of the palms, which in turn resulted in heavy yield losses for 3 years after infestation. Periodical checks are therefore necessary, with sampling at the rate of 2 trees/ha; the economic threshold was 10 larvae/frond on young and 20-25/frond on mature trees. If the trees were too tall or the attack too severe or too widespread for hand collection of larvae and cocoons, the most effective products for use in sprays were carbaryl at 1.2 kg toxicant/ha or a preparation of Bacillus thuringiensis at 1 kg toxicant/ha for small localised foci and the pyrethroids deltamethrin (Decis) at 10 g/ha, permethrin at 30 g or fenvalerate at 20 g/ha for larger areas. The elimination of preferred wild alternative food-plants such as Metroxylon sp. from round the edges of coconut plantations helped to prevent foci of the pest from becoming established near coconut.