Ophiocordyceps is a genus (closely related group) of fungi that grow on insects and other small arthropods . There are over 100 species of Ophiocordyceps. One noted species is the parasitic Ophiocordyceps unilateralis, sometimes called the “zombie-ant” fungus. Another species, Ophiocordyceps sinensis, is used in traditional Chinese and Tibetan medicine. These species and others were once thought to be part of another genus of fungi, Cordyceps. However, genetic studies revealed that some Cordyceps species were not closely related to the rest of the genus. These species were placed in a new genus, Ophiocordyceps.
O. unilateralis grows inside the bodies of carpenter ants in tropical forests. The fungus enters the ant as a spore and multiplies inside the body undetected. Eventually, the fungus appears to take control of the infected ant, dramatically altering its behavior. The ant will involuntarily climb to a height where conditions of temperature and humidity are ideal for the fungus to thrive. The ant will then permanently lock its mandibles (jaws) to a leaf or twig, holding the body in place as the ant dies and the fungus continues to grow. Eventually, a spike will emerge from the base of the dead ant’s head. This spike, called a fruiting body, releases spores, spreading the fungus to new ants.
O. sinensis grows on caterpillars of the ghost moth. Eventually, the caterpillar dies, and the fruiting body emerges as a spike from its head. The fungus and the caterpillar are taken together in traditional Chinese and Tibetan medicine. Some people take them as a dietary supplement , often under the name “caterpillar fungus” or cordyceps. The supplement is said to relieve muscle fatigue; improve kidney, liver, and immune system function; and fight the effects of aging. These claims have not been proven.
