Cone-nosed Bug (Triatoma spp.)

The true bug Family Reduviidae has more than 6,000 species, which are generally called "Assassin Bugs" by virtue of their rabidly predatory nature -- they are also nocturnal, seeking mainly other arthropods as prey, but some species of them are infamous for their attacks on humans (typically while the latter are sleeping). These are also called "Kissing Bugs" (based on their tendency to prefer exposed portions of the human face, and softer portions of that such as the lips or ears), and "Cone-nosed Bugs", the basis for which is obvious from the image above. This name is widely used in Arizona.

Note in the image above our local version of the bug (taken from an exposed packrat nest on May 14, 2008) may be seen in a dorsal view (Click on the images to enlarge). This specimen is about 2 cm long, not counting antennae. The red edge to the abdominal banding shows clearly here, a characteristic feature of our version. Below, the red edge also shows in this ventral view, as do the powerful forelegs, but the antennae are not in focus.

This image below shows the antennae better, and also the powerful prey-grasping forelegs.

Most Cone-nosed Bugs have short, slightly curved stabbing beaks, which pierce the cuticle (or skin) of their prey, and as sight-oriented predators they have well-developed eyes (noteworthy in the enlargement at the top, indeed in all images). Their forelegs are hyper-strong for grasping prey. The sub-family Triatominae, which includes our own species of human-attacking Cone-nosed Bugs prey specifically upon the blood of (mostly warm-blooded) vertebrates, and are the ones responsible for the trypanosomiasis which can infect humans, called "Chagas' Disease", a chronic and debilitating protozoan infection which is widespread in the New World tropics and now reaches as far as south Texas and Southern California. We may wonder how long it will take to reach southern Arizona.

In our area, Cone-nosed bugs typically occupy nests of our White-throated Woodrats (Packrats), where they find convenient shelter and mammalian blood-hosts, and from whence they emerge in April and May before the rains and when nighttime temperatures are warm. When their mouthparts bite into their prey, they inject their own saliva into their host while they suck the victim's blood. This exchange causes the victim's body to react: in humans, "Symptoms of the bite range from mild itching, severe joint pain, nausea, chills and dizziness to anaphylactic shock" (Resh & Carde, cited on main Arthropod page, p. 959). Anaphylactic shock is the severest form of allergic reaction, which may drop blood pressure to the point of death, so the bite of a Cone-nosed Bug is no joke. The wound may also become severely infected.

Cone-noses are attracted to lights during the nighttime, and so their presence can be readily determined seasonally. The Triatoma species deposit their barrel-shaped eggs in their Packrat nests, and their wingless nymphs hatch after some weeks, developing through a series of incomplete metamorphoses as they "mask" their bodies with debris. Nymphal developments extend over seasons, adults emerging after 3 years.


Note: the image at right comes from a photo by B.M. Drees, from Drees, B.M. and John Jackman, 1999, Field Guide to Texas Insects, Houston, Texas: Gulf Publishing Company. As you can see above, our Arizona species are somewhat different, but this very good image nicely shows the major diagnostic features including edge-banding on the abdomen.

But this type lacks the red-edging of our Cone-nose.