metarhizium anisopliae or why your ants maybe dying.

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TheAntVoyeur
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metarhizium anisopliae or why your ants maybe dying.

Post: # 74003Post TheAntVoyeur
Thu Sep 24, 2020 11:46 pm

I'd like to talk a little about the pathogenic fungus Metarhizium anisopliae.

This fungus is found in soil all over the world and causes disease in insects by acting as a parasitoid.
It is also known as green mascardine disease due to its green spores. It is easily transmitted from insect to insect particularly affecting those that live in close proximity with one another.
When the spores, referred to as conidia, come into contact with a host they germinate, a hypae penetrates the cuticle and the fungus begins to grow, killing the insect within a few days.
As it grows it releases insecticidal cyclic peptides that break down its internal organs for consumption.
Once the insect is dead it will turn red and with enough humidity the cadaver will develop a white mould that turns green as spores develop.

Insects, however, have defenses.
Ants protect against it by cleaning themselves and their nest mates with their antibacterial/fungicidal saliva or by spraying formic acid. In the cases where infection is too severe, workers will leave the nest to die somewhere away from the colony. They may even be dismembered by their kin.
In the case of infected pupae, the workers will open the cocoon, bite the ant inside and spray formic acid into the wounds, which kills both fungus and pupae.

I currently have two Myrmica Rubra colonies under attack from this pathogen. One is on the brink of being wiped out.
I have been using lemon slices but to no avail.

I examined 5 dead ants beneath a microscope and was able to observe on all of them patches of green or grey.
Each worker has followed the same pattern of twitching and spasming for two to three days before finally expiring. One of the colonies is dismembering workers and the two doing the job sit outside until their own spasms begin.
I was unsure about what was causing this until I spotted a worker with a red larvae doing its mourning laps around the outworld.

I have spent 3 weeks observing this, sifting through scientific papers and articles trying to work out what is happening. I am sure this is not the only pathogen that effects our ants, but this is the one I'm facing at the moment and wanted to share my findings and hopefully get a bit of discussion going on the matter.

Here are some links to some of the articles I have read.

Metarhizium anisopliae on wikipedia:
https://en.m.wikipedia.org/wiki/Metarhizium_anisopliae

Metarhizium anisopliae in relation to ants.
https://www.sciencedaily.com/releases/2018/01/180109113231.htm
2x Myrmica Rubra - r.i.p
3x Lasius Niger

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antnest8
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Re: metarhizium anisopliae or why your ants maybe dying.

Post: # 74023Post antnest8
Fri Sep 25, 2020 10:01 am

Scary, Thank you for sharing!
Some of My Informative Sheets
https://forum.AntsCanada.com/viewtopic.php?f=37&t=19099
Includes :
  • Ant Care Sheets
    Queen Hunting
    How To Identify Ants
Goal is to become #2 poster on the forum

TheAntVoyeur
Posts: 11
Joined: Mon Aug 31, 2020 10:24 pm
Location: In bed

Re: metarhizium anisopliae or why your ants maybe dying.

Post: # 74036Post TheAntVoyeur
Sun Sep 27, 2020 8:15 pm

No prob Bob!

I noticed few posts here and there about colonies dying out for no apparent reason. The main response seems to be "it just happens", or "there are many reasons why it could happen".

Rather than posting "bruh, muh antz r dyin' please halp!", I wanted to do some leg work so I can shed some light on the matter.

So far the best treatment seems to be to remove and euthanise any worker that begins exhibiting symptoms.
2x Myrmica Rubra - r.i.p
3x Lasius Niger

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