Husker

She watched as the figure shambled slowly across the shifting dunes. It seemed to have no purpose, but Fasa knew that the husk was searching for one thing: water. The lifeblood of the desert, essential for all life. Even a parasite as wretched as the husker needed it to survive.

Huskers are a type of desert-dwelling parasite which infest the digestive systems of their hosts and eventually gain control of the host's nervous system. It is not uncommon to see the shambling corpses, known as husks, wandering across the desert after having been taken over by this deadly parasite.

Habitat

Huskers live in arid, warm climates. They are typically found in deserts but can also survive in grasslands and other similar areas. They rely on still or slow-moving pools of water to reproduce and lay eggs in and for larvae to survive the initial stages of their early lives. Husker larvae feed on zooplankton and phytoplankton, but eventually require a living host to obtain the resources they need to grow and thrive.

Morphology

In the larval stages, the husker resembles a small maggot, but it is microscopic and impossible to see with the naked eye. They possess no eyes, but have a formidable set of sharp mandibles, used for catching food or gnawing through matter. Researchers have found that these larvae have clear bodies and one can see food and nutrients passing through the digestive system along with a vast network of blood vessels.

At a certain point in the life cycle of a husker, the larvae go through a pupal stage. They secrete a special mucus which hardens into a casing around the larva, keeping them safe while they go through metamorphosis and become adults.

Adult huskers grow rapidly once they exit their pupae. At this point, they have grown six legs equipped with tiny claws for gripping, and their bodies are covered in a hard, sand-brown exoskeleton, resembling termites in shape. Females lay thousands of microscopic eggs.

A Deadly Parasite

Huskers spent the early days of their life cycle in bodies of water, commonly oases. When a larger organism swallows water containing these larvae, the infestation of the new host begins.

Upon entering the host's digestive system, larvae burrow through the lining of the stomach and intestinal tracts. Because they are so small, the host may experience only a slight sensation of pain or nausea as the tiny creatures make their way into the rest of the body, headed upward to the chest and neck area. Here, they pupate for several weeks until the adults are ready to emerge. This is when the true infestation begins. The adults are larger, and burrow through the host to reach the spinal cord and blood vessels by chewing through the host's flesh with their sharp mandibles. At this point, the host experiences increasing pain as the parasites grow and feed inside them.

When the huskers reach a blood vessel, they bite into it and begin to drain blood from the host, gorging themselves until they nearly burst. Meanwhile, the huskers located near the spinal cord or other important components of the nervous system begin to hijack the host. Huskers can emit small electrical charges which can send nerve impulses racing along the host's nervous system. This essentially allows the parasites to take some kind of control over the host's body.

After a short time, the host succumbs to the loss of blood and eventually dies. Their body, however, is so effectively dried out that it is essentially mummified, allowing the huskers to remain sequestered inside and out of the elements. Huskers retain rudimentary control over the corpse's limbs, enough to move them about and keep the host mobile. This strange and frightening scene led to the bodies of these late hosts becoming referred to as "husks" by onlookers as they shamble across the desert mindlessly.

At this late stage in the parasites' lives, they have one goal: find water to reproduce. To do so, they keep the husk moving across the desert until it comes in contact with any body of water. The parasites rely on magnetic fields to stay oriented, but have no idea where a suitable water source may be. This often leads to the husks shambling into rivers, streams, or the ocean, none of which are suitable places to reproduce. However, the parasites do not know this and exit the body, where they either mate and lay eggs if in fresh water, or die from exposure to salt water if the husk happens to enter the ocean. The eggs are swept downstream with the adults until they reach a place where the current slows enough for the eggs to settle in the riverbed. Otherwise, they end up in the ocean and are destroyed.