3 replies to this topic

[AntBooper600]

I have been raising several Lasius queens, but there is something really bad. There are fly cocoons in the test tubes, and the queen ants are dying. I have been checking on the queens every day, and I just see more and more fly cocoons. The queen ants die shortly after the cocoons appear. There are no signs of fly eggs, maggots, or adult flies. Could these be parasites? There is also an unknown object in one of the test tubes that looks like it could possibly be a badly damaged fly cocoon.

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[AsdinAnts]

The queens had eggs laid inside of them, the culprit is usually some type of parasitic fly. Try looking into the genus Phoridae.

 

There’s nothing you can really do for the queens that have been infected, but you can try to separate all of the queens you have in multi-queen setups.

 

What happened?

This happens during nuptial flights, phorid flies (along with others) lay their eggs inside of queens ants either while they are flying, or looking for a place to make a founding chamber. During the time the queen is in her founding chamber, the fly egg will hatch and then the fly larvae will eat the queen from the inside. Once the larvae is ready to hatch, it will eject (either eat or get laid) itself out of the queen, and cocoon itself.

 

Whatever you do, DO NOT release those cocoons or queens, either crush and feed the larvae to an already exisiting colony, or crush it and throw it in the trash. As for the queens, keep them separate and wait for something else to happen, if no more fly larvae/cocoons come out of the queen, then I think she is fine. 

Edited by AsdinAnts, June 14 2024 - 11:03 AM.

[Locness]

Isolate and incinerate the infected. For the emperor.

[Ernteameise]

This is a totally normal parasite of Lasius ants, that goes by the name Strongygaster globula. It is a fly.

I even feature it in my ant health talk next week at the vet conference, because in my youth, most Lasius queens I collected, had these parasites hatching out of them. Fascinating to watch, but a bummer, because no colony will develop and the affected queen will die.

It infects new queens, lays eggs on them and the larvae develop in the gaster.

When they pupate and crawl our of the host gaster, the queen, who will not be able to lay eggs (her insides are eaten), will care for the fly. When the fly emerges from the cocoon, it will fly off, to infect NEWLY formed queens (which will have their nuptial flights now).

Totally normal parasite life cycle and part of nature. Parasites are part of an ecosystem and part of our environment and play an important role- they are NOT yuck and NOT "evil".

(if you want to see evil, I dare you to visit any industrial slaughterhouse)

I am a veterinary parasitologist, by the way.

 

Anyways, bottom line is-

The infected queens will die and you can remove them

The uninfected queens are fine

The flies that hatch will go on to infect new queens (if you release them), but they will not go after your old ones (no use, they have used up all the nutrients that the flies need for development and that are usually used to produce the first eggs and start a colony).

So your old, unaffacted queens are fine either way.

 

As for releasing the flies-

as we said with the release of captive colonies- if you collected the queens with flies locally, you can release them again, since they are part of an ecosystem.

If you caught them in a different area, please do not release but do kill them.

You do NOT want to release foreign parasites to an environment. That causes all kinds of trouble.

 

My 2 cents as a veterinary parasitologist.

Edited by Ernteameise, June 14 2024 - 9:38 PM.