Phaonia trimaculata
| Phaonia trimaculata | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
Phaonia trimaculata |
||||||||||||
| Systematics | ||||||||||||
|
||||||||||||
| Scientific name | ||||||||||||
| Phaonia trimaculata | ||||||||||||
| ( Bouché , 1834) |
Phaonia trimaculata is a fly from the subfamily Phaoniinae .
Appearance
Adult flies are between 0.5 and 0.7 mm long and steel-blue in color with brown-black markings. They resemble the common housefly . The larvae are up to 1.2 cm long and yellow-white in color.
biology
The larva of Phaonia trimaculata lives predatorily ( predator ) on larvae of the great rapeseed weevil ( Ceutorhynchus napi ) and the spotted cabbage weevil ( Ceutorhynchus pallidactylus ) in winter and summer oilseed rape , as well as in turnip rape . It is also reported that it can also be regarded as a predator of the larvae of the cabbage fly ( Delia radicum ) on cabbage and swede .
The adult flies lay their eggs in stems of oilseed rape plants, which have been torn open or burst open by the infestation of the rape stem weevil. Late frosts can also encourage the stems to burst. It is not possible to lay eggs in intact rapeseed stalks. From the end of April to the end of May, the larvae of Phaonia trimaculata are found in the rapeseed stems, where they feed on the larvae of the stem pests. Sometimes only the indigestible head capsules of the larvae of the stem pests remain in the plant pulp. The pupation of the fly larvae takes place in the rapeseed stem from mid-May. After about 18 days, the adult flies hatch and leave the rape plants through the broken stems.
credentials
- ↑ R. Fritzsche (1955): Phaonia trimaculata Bouché as a parasite of the large rapeseed weevil Ceutorrhynchus napi Gyll. and the spotted cabbage weevil Ceutorrhynchus quadridens Panz. News bulletin of the German Plant Protection Service 9, 35–36
- ↑ K. Smith (1927): A study of Hylemyia (Chortophila) brassicae Bouché, the cabbage root fly and its parasites. Ann. Appl. Biol. 14, 312-330
- ^ F. Keilin (1917): Recherches sur les Anthomyides à larves carnivores. Parasitology 9, 125.
literature
- J. Wadsworth (1915): Note on an Anthomyid fly. Phaonia trimaculata Bouché, new to the British list. Entomol. monthly likes. 51, 142-143.
- David V. Alford: Biocontrol of Oilseed Rape Pests. Blackwell Publishing, Oxford 2003, ISBN 0-632-05427-1