A parasitic fungus is turning Ontario creepy crawlies into suicidal zombies

A terrifying species of parasitic fungus found in Ontario can control the minds of millipedes, turning them into suicidal zombies solely focused on aiding the spread of this fearsome organism.

Arthrophaga myriapodina is a killer fungus unique to the North American northeast, with a range that covers much of Southern Ontario and parts of Quebec, from spring to late fall, typically within 24 hours of rainfall.

The species targets three species of millipedes, including the Apheloria virginiensis corrugata, or flat-backed millipede, which is native to Ontario. 

Apheloria virginiensis is reported to wield a defensive secretion containing cyanide compounds that are toxic to humans and animals. 

However, these defences do little to ward off Arthrophaga myriapodina, which parasitizes the millipedes and controls their brains, creating many-legged zombies that climb to elevated spots before dying and allowing the parasite to spread.

You can find dead and dying millipedes hanging from branches, fence posts, and in other elevated positions in Ontario wooded areas, easily identified by the white to light brown pustules (I am sorry) that are "forcibly discharged" (okay, now I'm really sorry) from between the bugs' segments.

The relatively new species and genus of entomophthoralean fungus, first documented in the late 1800s, remains the only documented millipede pathogen from the order Entomophthorales, an order known as pathogens that attack a wide diversity of insects as hosts and cause behavioural changes within them.

As with its relatives in the order Entomophthorales, Arthrophaga myriapodina infect their hosts via direct penetration through the cuticle. From there, the infection spreads and the begins to manipulate the host's functions, driving it to climb to the highest elevation possible.

This phenomenon called "summit disease" is an evolutionary weapon common to many parasitic fungal species, encouraging hosts to climb upwards to their death to provide the fungus' spores with a better chance for dispersal and survival.

In the case of Arthrophaga myriapodina-infected millipedes, masses of pear-shaped conidia (spores) finally break through the critters, which are then dispersed by the wind to repeat the process in the next unlucky host.