carob moth (pomegranate fruit borer)

Symptoms

Small entry hole at the calyx end of the fruit, frass (sawdust-like droppings) visible there, soft-rotting interior with caterpillar present, premature fruit drop.

Easily confused with

• pomegranate black heart rot (Aspergillus niger)

  How to tell them apart: Aspergillus niger black heart rot shows a dry-to-powdery black, sooty fungal mass filling the central fruit cavity and coating the aril clusters, often with no visible external entry hole — the rind may look sound while the inside is uniformly blackened and dusty. Ectomyelois ceratoniae (carob moth) instead leaves a clear larval entry tunnel, usually through the crown/calyx, with brownish frass (sawdust-like droppings), silken webbing, and one or more cream-coloured caterpillars (up to ~15 mm) with a darker head boring through the arils. With the moth, the browning is irregular and follows the feeding galleries rather than spreading as a uniform sooty black; check the calyx end for a frass-plugged hole and webbing, which Aspergillus never produces.

• Mediterranean fruit fly

  How to tell them apart: Ceratitis capitata (Mediterranean fruit fly) damage starts as a tiny pinprick oviposition 'sting' anywhere on the smooth fruit skin, often surrounded by a small soft, water-soaked, browning halo; cut the fruit and you find legless, creamy-white maggots (pointed at the head, blunt at the rear) wriggling in softening, fermenting flesh with little visible webbing. Ectomyelois ceratoniae (carob moth) damage typically enters through the crown/calyx end where the petals meet, and inside you find a pinkish-grey to whitish caterpillar with a distinct dark head capsule and tiny legs, plus copious silk webbing and dry brownish frass (droppings) matting the arils together. So: messy silk + frass + a true caterpillar with a head capsule and legs = carob moth; a clean external sting halo + a legless headless-looking maggot in wet rot = medfly.

• peach fruit fly (Bactrocera zonata)