Feltiella acarisuga is a gall midge, just like the aphid predator Aphidoletes. The adult Feltiella acarisuga lays yellow-coloured eggs of about 0.25 mm amongst red spider mite colonies. After about two days, a creamy brownish yellow larva hatches, which devours red spider mites.

After about one week, the larvae pupate. The fully-grown larvae are 1,7 to 1,9 mm long and have a diameter of 0,4 mm. The pupae of Feltiella acarisuga look just like white fluff and are usually found near the veins of the leaf. They are from 1 to 1,5 mm long. The total life cycle varies with temperature, but generally takes about 2 to 4 weeks.

Feltiella acarisuga is also found in nature, and can be often seen in crops towards the end of the summer.

Feltiella acarisuga has already proved its use in extensive practical experiments in cucumbers and tomatoes. In particular for tomatoes, where the biological control of red spider mite has so far been very difficult, Feltiella acarisuga is a welcome improvement.

Feltiella acarisuga will become an important component of the biological control of red spider mite, particularly on account of the following advantages:

	In contrast to the predatory mite Phytoseiulus, Feltiella acarisuga proves to be able to control effectively red spider mites in tomatoes. In case of heavy infestations of red spider mite, Feltiella acarisuga can be used in combination with the special tomato-Phytoseiulus (Phytoseiulus-T-System).
	Feltiella acarisuga also controls overwintered red spider mite, which may be important in spring and autumn.
	The "toxic" carmine spider mite (Tetranychus cinnabarinus), which can do great damage in crops, like carnations and tomatoes, can be effectively controlled with Feltiella acarisuga.
	The adult Feltiella acarisuga are capable, while flying, of tracking colonies of red spider mite. The great detective capacity of Feltiella acarisuga is an important advantage in comparison with Phytoseiulus, which can only spread while walking. Especially, in ornamentals, where it is a very laborious business to scout for colonies, this means an important step ahead.
	Because of its excellent flying capacity, putting out Feltiella acarisuga requires very little work.
	Feltiella acarisuga larvae eat both eggs, nymphs and adults of red spider mites. Feltiella acarisuga eats at least 5 times as many red spider mites per day as Phytoseiulus.
	Field tests show that Feltiella acarisuga is also active in cold and dark weather in spring and autumn. This is another important advantage in strawberries and soft fruits.
	Feltiella acarisuga can be found back in the crop easily. Both its larvae and its pupae are easily visible.

Experiments have shown that Thiovit (sulphur), Rubigan and Rovral are safe to use. Torque can influence the population build-up of Feltiella because the red spider mite is killed. For more information, check the side-effects list.

Feltiella acarisuga is supplied as pupae on paper pieces in pots of 1 litre. One pot contains 250 pupae. These pots are very user-friendly. By piercing the paper disc in the cover, the adult gall midges can escape after hatching. The pots are simply placed in the shadow on the ground in the crop at the beginning of a row.

Biobest can also deliver this beneficial gall midge in a reduced package. Feltiella-System LV (Low Volume) contains 250 pupae on paper pieces, packed in a small plastic dish. By opening the dish in the crop, adult gall midges can easily escape and search for spider mite hot spots.

	In spring, when the red spider mites come out of their hibernation, introduce 2-3 pots per hectare weekly. It is best to place the pots in the vicinity of commencing red spider mite colonies.
	Heavy infestations across the entire greenhouse in spring are best controlled by putting out 10 pots (250 pupae per pot) per hectare weekly, during 6 successive weeks. The purpose is to build up a Feltiella acarisuga population across the entire crop as soon as possible.
	In summer, the number of introductions can be limited to 4, because the life cycle of Feltiella acarisuga becomes shorter at increasing temperatures.

We recommend to apply Feltiella acarisuga during the building-up period in combination with Phytoseiulus or Tomato-Phytoseiulus. In the beginning, Feltiella acarisuga will be found back in particular in larger colonies of red spider mite. As the Feltiella acarisuga population increases, Feltiella acarisuga will also be found back in smaller colonies of red spider mite.

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