Plants and Fungi

Plants and Fungi

Killer Fungi

insect killing fungi

These past few weeks the rainy season, or lack of it this year, seems to have put in a mini resurgance and we have witnessed some very strong storms. I had thought the rainy season had somewhat failed this year, and had noticed dry leaves and dry stream beds back in early October. But the resurgance returned the forests to their humid best and it was like small gift to play with for a few short weeks. As a result I had quite a few sightings of some impressive humidty lovers, fungi. Entomopathogenic fungi to be exact. Ento... what?

Entomopathogenic fungi are killers, macabre yet sophisiticated killers at that. Some species are indeed referred to as "zombie fungi" because of their mind altering actions on their insect prey.

They usually attach to the external body part of a particular insect in the form of microscopic spores. Under the right wet and humid conditions, these spores will germinate and colonize the insect's outer body, next they will bore through the insects body to get into the body cavity. Then the fungi will proliferate throughout the body of the insect whilst it still lives. Macabre. After some time the insect is killed and the fungi will then attempt to conclude its life cycle by dispersing spores once again, in the hope of infecting another victim. Sophisticated. The fruiting bodies of the different species of entomopathogenic fungi take on different forms and colours and can be very exotic, indeed bizarre, to the eye.


Akanthomyces pistillariae formis 2

One of the most infamous of the entomopathogenic fungi genus are the entomopathogenic Cordyceps. Cordyceps means "club head", referring to the shape of the fruiting bodies when they emerge from their host's body. Their spores are very potent, and this killer fungus can wipe out entire colonies of insects in some cases.

Different species of entomopathogenic Cordyceps (there are approximately 400 described species and many more remain undescribed) attack different and specific insect orders. These orders include moths, crickets, ants, wasps, flies, roaches, spiders and bees to name but a few.

Made infamous by a BBC wildlife production, with David Attenborough, the Ophiocordyceps unilateralis (see picture at top of article) is an entomopathogenic fungus predominantly found in tropical forest ecosystems. Also known as the "zombie fungus", and was first discovered by my most favorite of naturalists, Alfred Russel Wallace, in 1859.

O. unilateralis amazingly manipulates the behavioral patterns of an infected ant, of the Camponotui tribe (Carpenter Ants). The infected ant, under the influence of the fungi will leave its nest and foraging trails, heading for the forest floor in search of an area with a temperature and humidity level suitable for fungal growth. The infected ant will then use its mandibles to affix itself to a major vein on the underside of a leaf and will eventually die, leaving O. unilateralis in the perfect setting to sprought fruit and release its spores.

Most of the time, we like to consider what's beautiful, four legged and usually furry in the natural world. However, sometimes the sheer complexity of evolution and her resulting bio-diversity can only be truly appreciated in the more macabre side of the forest's inhabitants.

Cordyceps tuberculata 1

 

Cordyceps tuberculata 2

 

Hymenostilbe dipterigena 2

 

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onflipflops's Avatar
onflipflops replied the topic: #2512 4 years 1 day ago
Great article!

"Each species is a masterpiece, a creation assembled with extreme care and genius." > Edward O. Wilson

"An understanding of the Natural World and whats in it is a source of not only a great curiosity but great fulfillment." > Sir David Attenborough

“Climb up on some hill at sunrise.  Everybody needs perspective once in a while, and you’ll find it there.” > Robb Sagendorph