It is small (wingspan of 0.6”-0.8”), dark brown to grey in colour. The moths are active at night. Female moths lay single eggs on ripening citrus fruits. The young caterpillar mines just beneath the surface, or bores into the pith causing premature ripening of the fruit and fruit drop.
The initial symptom on the fruit is a yellowish round spot with a tiny dark centre where the insect entered the fruit. In a later stage brown patches appear on the skin, usually with a hole in the centre. The young caterpillar is creamy-white with a dark brownish head. With age the body turn pinkish red. The fully-grown caterpillar is 15 to 20 mm in length. When mature the caterpillar leaves the fruit and pupates in the soil or beneath surface debris. Navel oranges seem to be the most heavily attacked. Grapefruit is less susceptible. In lemons and limes larval development is rarely, if ever, completed.
Managing Garden Insects Begins with a Question: Friend or Foe?
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”-0.8”), dark brown to grey in colour. The moths are active at night. Female moths lay single eggs on ripening citrus fruits. The young caterpillar mines just beneath the surface, or bores into the pith causing premature ripening of the fruit and fruit drop. 
ntre where the insect entered the fruit. In a later stage brown patches appear on the skin, usually with a hole in the centre. The young caterpillar is creamy-white with a dark brownish head. With age the body turn pinkish red. The fully-grown caterpillar is 15 to 20 mm in length. When 
mature the caterpillar leaves the fruit and pupates in the soil or beneath surface debris. Navel oranges seem to be the most heavily attacked. Grapefruit is less susceptible. In lemons and limes larval development is rarely, if ever, completed.