Macrolophus pygmaeus
A slender, bright green predatory bug about 3 mm (1/8 in) long, native to the Mediterranean, and the standard whitefly predator in European greenhouse tomatoes. It also eats Tuta absoluta eggs, spider mites and aphids. It builds up slowly, so it goes in early. It is not sold in the United States. Because mirids also feed on plants, M. pygmaeus has not been brought into the US even for evaluation. American growers use the native Dicyphus hesperus, which does a similar job.
At a glance
- Mode
- Predator; also feeds on the plant
- Rate
- Biobest: 5–10 /m² on hot spots, to 0.5–2 /m² overall; Koppert: 0.25–5 /m² per release
- Ships as
- Adults and late nymphs in a carrier (vermiculite, husks or paper)
- Temp
- Best above 68 °F (20 °C)
- Build-up
- At least two months
- Availability
- Europe and UK; not sold in the US
How it works
Adults and nymphs hunt on foot, fast even on hairy tomato leaves, and suck their prey empty through a piercing beak, leaving an empty shell, sometimes collapsed, with a small hole. Whitefly is the favourite: Biobest puts an adult at 40–50 whitefly eggs a day, and it also takes larvae and pupae of both greenhouse and tobacco whitefly. It feeds on spider mites, aphids, leafminer larvae and moth eggs as well, and Biobest notes that tomato growers using it spray less for caterpillars.
It is slow. Eggs laid into leaf, vein or stalk tissue hatch after 11 days at 77 °F (25 °C), or 37 days at 59 °F (15 °C). The five nymphal stages then take about 19 days at 77 °F, or 58 days at 59 °F, and females live about 40 days at 77 °F. The bug can live on plant sap, but Koppert says it breeds poorly without animal prey, so suppliers sell supplementary foods (Koppert's Entofood and Artefeed, Biobest's Nutrimac and Artemac) to build numbers early. The same plant feeding is the risk: with little prey and very high numbers it can damage flowers and fruit.
Is it established?
Expect to see almost nothing for the first month. Biobest says the bug can hardly be found for 3–4 weeks and needs at least two months to build a working population.
- WEEKS 1–4Hard to find; keep parasitoids going against whitefly meanwhile
- WEEKS 4–8First home-bred nymphs, yellowish green when young, bright green later
- MONTH 2+All stages present; empty, collapsed whitefly scales with a small puncture hole
- WATCHHundreds per plant, or 50 in the head, with little prey — the level at which Biobest warns of crop damage
Release & handling
Biobest ships late nymphs and adults on vermiculite in a tube of 250 or 500; the LS Systems pack is 500 adults on honeycomb paper. Koppert ships adults and nymphs in a 100 ml bottle (wood chips and buckwheat hulls) or on card strips in a tray of 500. Release them promptly: Koppert allows one to two days at 46–50 °F (8–10 °C) in the dark with the bottle lying flat.
Release within a day or two
Short storage only, at 46–50 °F (8–10 °C) in the dark (Koppert, Biobest).
Piles on the hot spots
Release in whitefly hot spots or the warmest part of the house, in piles large enough for a population to build (Biobest). Koppert sprinkles the bottle thinly on rockwool slabs or leaves, 6–10 points per bottle.
Early in the crop
Biobest introduces it four to eight weeks after planting, in two to four releases one to two weeks apart.
Add food if prey is scarce
Scatter the supplier's supplementary food at the release points so the population builds without waiting for whitefly.
Pesticide sensitivity
Biobest warns of crop damage (poor fruit set, flower drop, misshapen trusses, feeding spots on fruit) when numbers are very high and prey is scarce, especially in cherry and small-truss tomatoes. Koppert gives more than 100–150 bugs per plant as the risk level. Check a product →
When to choose something else
Macrolophus is a long-season tool for European tomato and aubergine houses. Choose something else when:
- You grow in the US — it is not available; the native Dicyphus hesperus is sold by Arbico Organics, and mullein banker plants help it build up, though a greenhouse trial (Smith and Krey, 2019) found it helped but was not enough on its own
- Whitefly is already heavy — Macrolophus takes two months to build; use parasitoids such as Encarsia formosa or Eretmocerus eremicus, which Biobest pairs with it
- The crop is a sensitive cherry or small-truss tomato and prey is scarce — the plant-feeding risk is highest there
- The house is cool — development slows sharply below 68 °F (20 °C) and stops below 50 °F (10 °C)
Where to buy
Suppliers of Macrolophus pygmaeus listed alphabetically, not ranked. It is sold in Europe and the UK, not in the US: Koppert's US and Canadian sites do not list it. helpfulbugs takes no commission and does not sell insects.
- Biobest (Macrolophus-System)250 / 500EU / UK
- Koppert (Mirical)500EU / UK
- LS Systems (Biobest)500 adultsUK