Aphelinus abdominalis
A 2.5–3 mm parasitoid wasp with a black thorax and yellow abdomen, sold for the large aphids — potato aphid and foxglove (glasshouse potato) aphid. It kills in two ways: the female lays an egg in larger aphids and feeds on smaller ones, and Koppert credits the two about equally. Parasitised aphids turn into slim black mummies. It is slower than Aphidius but works over a wider temperature range, up to 35 °C (95 °F), which makes it the summer partner to the Aphidius wasps.
At a glance
- Mode
- Parasitoid and host-feeder
- Rate
- 0.25–4 /m² per release, repeated
- Ships as
- Mummies — 250 or 1,000 (US); 500 (Koppert)
- Temp
- 15–35 °C (Koppert); 10–32 °C (Biobest)
- Humidity
- 60–80 % RH (Arbico)
- Setting
- Greenhouse and indoor crops
How it works
The female uses her long ovipositor to lay in the larger aphids and feeds on the small ones for the protein she needs to make eggs; Sound Horticulture puts that host-feeding at about two aphids a day, and Koppert says the aphids killed by feeding and by parasitism are roughly equal. She prefers second and third instars. The adults walk far more than they fly, so they stay close to where they are released — a strength in a dense crop, a weakness across a large house.
The larva develops inside the aphid, which turns into a black, elongated mummy — less swollen than the mummy of Aphidius, which makes the two easy to tell apart when both are in use. At 20 °C (68 °F) the larva takes about 7 days inside the living aphid, and the mummy about 14 more before the new wasp emerges (Sound Horticulture). UConn describes it as working more slowly, but for longer, than the Aphidius wasps, and Biobest notes it suffers less from hyperparasitoids, which is why it earns its place in summer.
Is it established?
Count black mummies, not dead aphids. With this wasp, a colony that is shrinking without many mummies may still be working — the host-feeding leaves no mummy behind.
- FIRST DAYSAdults emerge from the carrier; leave the vial open so late emergers can get out
- ABOUT 2 WEEKSFirst black, elongated mummies in the crop near the release points (Koppert)
- ABOUT 4 WEEKSMummies with an exit hole — the next generation is out (about 14 days after the mummy forms, at 20 °C)
- AFTERMummies spreading slowly outward; keep releasing close to colonies, since adults walk rather than fly
Release & handling
Mummies arrive in a vial or bottle of carrier — wood chips in Koppert's pack. Arbico says use them within 18 hours of receipt; Koppert allows one to two days at 8–10 °C in the dark if you must hold them. Spread the carrier on rockwool slabs or in release boxes right beside infested plants, keep it dry, and leave it undisturbed for a few days.
Release the same day
Arbico: within 18 hours. Leave the vial open in the crop so later adults can still get out (Sound Horticulture).
8–10 °C, dark
One to two days at most (Koppert). Arbico says a cool place out of direct sun.
Right beside colonies
The wasps walk rather than fly and do not spread far. Use more release points, closer to the aphids.
Take them down first
Sound Horticulture advises removing yellow sticky cards before release.
Pesticide sensitivity
UC IPM rates pyrethrins, acetamiprid, flupyradifurone and bifenthrin as highly harmful to parasitoids, and neem oil, soil-applied imidacloprid and pymetrozine as moderately harmful. Soap, narrow-range oil, flonicamid and spirotetramat rate low. Check a product →
When to choose something else
Aphelinus is the slow, heat-tolerant wasp for large aphids. Choose something else when:
- The aphid is green peach or melon aphid — Aphidius colemani is sold for those, and in lab tests Aphelinus rarely accepted melon aphid
- You need quick results on potato or foxglove aphid — UConn notes Aphelinus is slower than the Aphidius wasps, so use Aphidius ervi
- Colonies are already established — add the gall midge Aphidoletes aphidimyza; Biobest pairs this wasp with it for curative control, and Koppert says it combines with its Aphidoletes product
- The aphid is oleander aphid on milkweed — in lab tests this wasp stung it readily but could not develop in it; UF/IFAS reports heavy parasitism by the wild wasp Lysiphlebus testaceipes, so conserve that instead
Where to buy
Suppliers listed alphabetically, not ranked. helpfulbugs takes no commission and does not sell insects.
- Arbico Organics250 / 1,000US
- Koppert (Aphilin)500GLOBAL
- Rincon-Vitova250US
- Sound Horticulture250 / 1,000US
Aphelinus abdominalis by target
Rate and timing differ by what you are releasing it against. Each page below is the program for one pest.