Debus emarginatus is a species of weevil widely distributed throughout the Old World tropics.
Distribution It is native to China, India, Sri Lanka, Indonesia, Japan, Laos, Malaysia, Myanmar, Philippines, South Korea, Thailand, Vietnam, Australia, Papua New Guinea and Solomon Islands.
Description The average length of the species is about 3.3 to 3.6 mm. The postero-lateral extensions of elytra are short, and less than the width of apical emargination. The declivity is shallowly excavated. Elytral declivity clearly, confusedly punctate.
Host plants A polyphagous pest, it is found from many host plants.
Abies fabri Azfelia palembanica Castanea argentea Castanopsis Cinchona Cyrtophyllum giganteum Dipterocarpus baudii Durio zibethinus Falcataria moluccana Ficus Koompassia excelsa Mangifera foetida Neobalanocarpus heimii Palaquium Pinus tabulaeformis Pinus yunnanensis Populus Quercus Rubroshorea leprosula Sarcocephalus cordatus Symplocos Terminalia
Control It is a high-risk quarantine pest where they show inbreeding, with the males generally mating with their sisters within the parental gallery system before dispersal. Adult beetle does not actually feed on the plant material but uses it as a medium for growing the fungus which is the larval food. They are mostly found in felled timber. Attacked plants show signs of wilting, branch die-back, shoot breakage, chronic debilitation, sun-scorch or a general decline in vigour.
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