“At night I experienced an attack of the Benchuca, the great black bug of the Pampas. It is most disgusting to feel soft wingless insects, about an inch long, crawling over one’s body. Before sucking they are quite thin, but afterwards they become round and bloated with blood, and in this state are easily crushed. They are also found in the northern parts of Chile and in Peru. One which I caught at Iquique, was very empty. When placed on the table, and though surrounded by people, if a finger was presented, the bold insect would immediately draw its sucker, make a charge, and if allowed, draw blood. No pain was caused by the wound. It was curious to watch its body during the act of sucking, as it changed in less than ten minutes, from being as flat as a wafer to a globular form.”
– Charles Darwin
This little critter is known to many by different names such as kissing bug, assassin bugs and in Latin America as chinches. They are members of the Triatominae family. They are found throughout the Americas as well as in other continents. They are infamous for several reasons, one for the sucking of blood and the other for spreading Chagas disease. They undergo a five stage instar resulting in a complete metamorphosis. In its first stage a wingless nymph hatches from an egg, and finally, the fifth instar turns it into an adult, acquiring two pairs of wings. During the day the bug hides in the thatched roofs and clay walls and at night comes out in search for blood when the host is asleep. Kissing bugs have an arsenal of ways to locate a host. They can use heat, carbon dioxide emanating from breath, as well as acids from skin, hair, and glands from vertebrate animals. During the night, adults fly to houses, attracted by light.
The bug flies or crawls normally to the mouth area, attracted by the carbon dioxide being exhaled. This is how it gets its name of kissing bug. It gets the assassin name because the bug has an anesthetic that it gives off when it bites you so there is no pain. It is also notorious for spreading Chagas disease. Chagas is named after Carlos Chagas who first documented it in 1909. Trypanosoma cruzi is the parasite that causes the disease and is found on the feces of the kissing bug. Sometimes after bitting a host, the bug will defecate near the bite wound and the parasite enters the body and multiplies. The disease causes swelling in the eye area and sometimes a sore, then it goes dormant for many years, only to reappear and cause cardiac arrest. Considering that Charles Darwin died of heart failure, there is a high chance he was infected by Chagas but this was never proven.
I have seen them in many caves that I visit. I have done my best to stay clear of them over the years and to keep my guests away from them also. In particular, I see them in high numbers in the Rio Frio Cave, a large limestone cave in the Mountain Pine Ridge. Along the pathway you can find a few dead ones. Taking a closer look on the walls, in the tiny crevasses and rock formations, there are many. They are very likely feeding on bat blood but maybe, just maybe, catch a free ride on the many tourists that frequent the cave.