Life cycle: Citrus peelminer, Marmara gulosa, is a tiny dark moth that mates, deposits eggs on stems and fruit of citrus, the eggs hatch into larvae that molt 4 times and finally pupate in cocoons. For more information on the biology of this insect and the closely related citrus leafminer, see ANR publication 8321 Citrus Leafminer and Citrus Peelminer.
Host plants: Citrus peelminer can attack all varieties of citrus, but some varieties are more susceptible (can sustain more than 5% fruit damage). Susceptible varieties include: grapefruit, pummelos, and smooth-skinned navel orange varieties such as 'Fukumoto', 'Atwood', 'TI', and 'Barnfield'.
Damage: Citrus peelminer larvae attack stems or fruit of citrus (rarely leaves). The damage is on the surface of the fruit, but mining causes downgrading in the packinghouse and so is not tolerated, especially for export markets.
Distribution: Citrus peelminer is found in Mexico, Arizona and California.