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How to identify it
- The adult is a small, glossy, hairy fly, blue-black overall and about 3.5 to 4.5 millimeters long, with all-black legs and wings that extend past the tip of the abdomen when folded.[2]
- Its brick-red eyes are characteristic; related lance flies that also breed in figs have brown eyes.[2]
- Infested figs often show a purple discoloration on the side or around the opening at the tip (the ostiole), though green-ripening varieties may not change color. Cut open, they show brown, irregular feeding tunnels with frass.[2]
- Fully grown larvae chew their way out to pupate, leaving an exit hole, usually low on the side of the fig.[1][2]
Look-alikes
| Look-alike | How to tell them apart |
|---|---|
| Neosilba lance flies | Related lance flies that also develop in figs have brown eyes, and some lay eggs in the exit holes left by black fig fly larvae rather than in the ostiole.[2] |
Where it lives
Its range covers much of the Mediterranean region of Europe, southwestern Asia and North Africa, and it has spread to South Africa, Mexico and the United States. In California it was first detected by state agriculture staff in seven southern California counties at once; UC IPM lists Los Angeles, Orange, Riverside, Santa Barbara, San Bernardino, San Diego and Ventura counties. It has not been reported from the main fig-growing areas of the Central Valley.[2][1]
Biology and life cycle
It feeds only on the common fig (Ficus carica) and prefers small, unripe fruit, though ripe figs are occasionally attacked, mainly after harvest when young fruit is scarce.[1][2]
The female inserts her ovipositor (egg-laying tube) through the ostiole and leaves eggs in small clusters under its scales, usually 1 to 8 per fig. Eggs hatch in 3 to 8 days, and the larvae feed first around the ostiole and then through the rest of the fruit.[2][1]
Mature larvae leave the fig, drop to the ground and pupate in the soil, though pupae are sometimes found inside fruit. In Mexico the larval stage lasted 13 to 15 days and the pupal stage 11 days.[1][3]
Egg to adult takes roughly 18 to 25 days in warm conditions and 40 to 50 days when it is cooler. The fly spends the winter as a pupa in the soil and emerges in spring.[2][1]
There are 4 to 6 generations a year, more in warmer areas and fewer in cooler ones.[1][2]
Damage and signs
Health risk
UC IPM and the research literature treat it only as a pest of figs; they describe no risk to people.[1][2]
Control
Prevention
Do not move figs out of infested counties, since carrying fruit can spread the fly to new areas.[1]
Sanitation
Pick up and destroy infested figs, both fallen fruit and fruit still on the tree. UC IPM calls sanitation critical, and the 2026 review suggests destroying infested figs by burying them about 40 centimeters (16 inches) deep or sealing them in black plastic bags in the sun so no adults emerge.[1][2]
Traps and physical control
Check figs for feeding damage and exit holes, especially unripe fruit that has just fallen. McPhail-type traps baited with torula yeast can monitor adults, though how well they work is still being evaluated.[1]
Biological control
Biological control appears limited; no parasitoids have been found attacking it in Mexico or South Africa.[1][2]
Pesticides
No insecticides are registered specifically for this pest on California figs. Larvae inside the fruit are protected from sprays and there are no effective soil drenches for the pupae; insecticidal baits may help against adults. Consult a licensed pest control adviser and the county agricultural commissioner before using any chemical control.[1]
When to call a professional
If you find infested figs in an orchard or yard where the fly is not known, report it to your local UC Cooperative Extension farm advisor, the county agricultural commissioner or the CDFA Pest Hotline (1-800-491-1899).[1]
Common questions
- Why are my young figs turning purple and falling off?
- Black fig fly maggots feeding inside young figs often cause a purple discoloration and make the fruit drop early. Cut a few fallen figs open and look for maggots, brown feeding tunnels or exit holes.[2][1]
- Can I spray to stop black fig fly?
- Sprays do little because the larvae are protected inside the fruit, and nothing is registered specifically for it on California figs. Removing and destroying infested fruit is the key step.[1][2]
Sources
- University of California Statewide IPM Program, “Pest Alert: Black Fig Fly, Invasive Fig Pest Recently Discovered in Southern California (H. Wilson et al., rev. 2021).” ipm.ucanr.edu/legacy_assets/pdf/pestalert/pestalert_blackfigfly.pdf (accessed 2026-11-09)
- Insects (MDPI), via PubMed Central, “The Black Fig Fly, Silba adipata (Diptera: Lonchaeidae): Current Knowledge and Future Research Needs (R. Lasa et al.; Insects 17(3):247, 2026).” pmc.ncbi.nlm.nih.gov/articles/PMC13027197/ (accessed 2026-11-09)
- Insects (MDPI), via NCBI PubMed, “Bioecological Parameters of the Black Fig Fly, Silba adipata, Collected from Fig Crops in Mexico (E. Paniagua-Jasso et al.; Insects 15(11):883, 2024; abstract).” pubmed.ncbi.nlm.nih.gov/39590482/ (accessed 2026-11-09)
- iNaturalist, “Silba adipata taxon page (order and family).” www.inaturalist.org/taxa/689737 (accessed 2026-11-09)