Information Delia antiqua


The onion fly larvae are reared on an artificial diet. To stop their development, they are stored at 2-3°C shortly after pupating. Onion fly pupae are available at any time, but we prefer to ship them on Mondays. Pupae will hatch two weeks after their sending date.


Information Aleochara bilineata 

The beetles are reared on onion fly pupae at a temperature of 19-20°C. At this temperature it takes about 4 weeks from inoculation (infection of onion fly pupae with beetle eggs) until emergence of the first beetles. Most beetles emerge around 5½ weeks after inoculation and it takes up to 8 weeks for the last beetles to emerge.

The beetles are generally shipped as infected onion fly pupae, 3 weeks after inoculation. Because success ratio of the parasitation process is not 100%, not all pupae will contain beetles. From the unparasitized pupae flies will hatch 2 weeks after inoculation, which is still one week before the pupae are shipped. Beetles are send in surplus to guarantee that at least the ordered amount of beetles will emerge.

The rearing of beetles is mainly for our own use. Therefore supply at short notice is not always available, but of course it is free to inquire. When ordered 5 weeks in advance supply of up to 2500 beetles is nearly always possible. For bigger amounts it is advised to order even earlier.

For technical questions please contact Maarten de Korte (

To order flies or beetles please contact Dorina van Putten (

© 2013 De Groene Vlieg | Disclaimer | Algemene Voorwaarden | Contact


Voor een volledige werking van deze website wordt gebruik gemaakt van cookies.
Meer informatie over cookies > Accepteren