Feltiella acarisuga

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Feltiella acarisuga is a pink-brown predatory midge (family Cecidomyidae), its larva preys on mites from the Tetranychidae family.
The adults are small with curled antennae. Life cycle is very shot. F. acarisuga isn’t a predator and feeds mainly on aphid’s honeydew. Sometimes they can be seen sitting on a spider web of herbivorous mites under the crop leaves. The predatory midges are much smaller, paler, and more fragile than the adult sciaridae flies that can also be seen under the leaves. About 60% of the imago are females and each female of F. acarisuga lays up to 25 oblong eggs in a spider mite colony.

Life span

Eggs: The glossy, translucent, oblong eggs are deposited in the spider mite colony.

Larvae: The orange-brown larvae have 4 instars; the total development period is about 1 week. The larvae of the first stage are transparent, difficult to notice. As it grows, the larva becomes a yellow-orange with distinct white internal organs visible along the sides of the translucent body. The last 4th instar is the brightest. Larvae of the 3d and 4th instars feed on all spider mite development stages, leaving their empty chitinous membranes on plants in places of feeding. Having fed up enough, the larva creates a silk cocoon, usually attached to the veins of the leaf.

Pupa: A cocoon with a pupa can be located both on the upper and lower surfaces of the leaves. At first, the cocoon is white, but during the development of the pupa, it becomes darker. Before the escape of the imago, the pupa leaves the cocoon. The pupal instar lasts about 12 days at a temperature of 22 ° C. The empty pupal membrane often looks like a translucent white “finger” that sticks out of the hatched cocoon.

Feeding

The 3rd and 4th larval instars actively feed on spider mites. They consume all pest instars, sucking the contents and leaving their victims empty behind.

Feltiella acarisuga is not suitable for preventive application because it can not survive on the crop in the absence of spider mites. It should be released when the presence of spider mites is well known and can be used for additional control with other bio agents such as Phytoseiulus persimilis and Amblyseius californicus. An adult F. acarisuga can fly and colonize crop areas outside the place of release, but it can’t do this if there is a large spider mite number. Therefore, applications should be carried out all over the greenhouse area, affected by spider mites. An important point – if there are predatory mite eggs in the colonies of a spider mite, then F. acarisuga can also consume them. On a short light day, F. acarisuga reproduces diapausing pupae, that is why the predator isn’t used in winter even in a case of additional lighting. To apply the beneficial insects, place the bottle with cocoons in the glasshouse as soon as it is possible. Make a hole in a disk of a paper filter and leave the bottle in a dark place near pest colonies for several days to allow midges to fly.

Recommended standards for A. Andersoni applying

Package

1 litre – paper bag, contains 250 larvae of predatory midges.

Conditions and duration of storage

Use within 18 hours after receiving. Keep in a cool dark place (10-15 °C) until ready for use in a greenhouse.