Wednesday, May 25, 2016

Kissing Bug or not?

It's time for the Kissing Bug post again: Yes, we have them in the Southwest US.
In the Soutwestern US, they are neither new nor uncommon
They may carry the microbe that causes Chagas desease (Trypanosoma cruzi) in fact, studies showed that  
about 40 % of the Kissing Bugs around Tucson are infected 
 with Trypanosoma cruzi. .But so far they are not known to transmit it to humans here in AZ. Behavioral differences from tropical species may play a role. 
Some possible cases in Texas were reported (there are different species of Kissing Bugs there, the same genus, Triatoma, plus some others.)
Female Triatoma rubida in Tucson, AZ
 Adult Kissing Bugs fly to lights at this time of the year, from the end of May to the beginning of July. They are NIGHT-ACTIVE. But I have found them sitting under our kitchen light in the morning, still there from their nightly visit. They are very flat and can get through narrow openings under doors.
Nymph of T. rubida, stilll flightless
I've found nymphs (flightless) indoors since January. The dogs may bring them in? We have packrat middens too close to the house and should get rid of those.  That's were most Kissing Bugs grow up.

Side view of the elongate head of a Kissing Bug (conenose) At rest, the sucking mouth parts are folded back. They stretch forward when in use. Photo by Eric Eaton (detail)
Taxonomically, Kissing bugs belong to the order Hemiptera
so they are True Bugs, not Beetles. One characteristic of that group are the piercing, sucking mouth parts.

Several other True Bugs are often mistaken for Kissing Bugs
Let's separate the Kissing Bugs, also called Conenoses, from similar True Bugs that are often mixed up with the real thing.
Eastern Boxelder Bugs Photo by Seth Ausubel
Some hints: if you find bugs on flowers, or anywhere in the sunshine, bugs in big aggregations, on leaves or fruit: Those are NOT Kissing Bugs. Several related species of these
Rhopalidae (Scentless Plant Bugs) and similar Lygaeidae (Seed Bugs) are very common in Arizona. They feed on leaves and milky, fresh seeds piercing them with their probosces and sucking the juice.

 Here are the Small and the Large Milkweed Bug. They are plant suckers and not interested in animal blood at all. Both are smaller than our common Kissing Bugs in AZ.

Some of our Leaf-footed Bugsdon't have actual 'leaves' on their legs
A number of Leaf-footed Bugs (Coreidae) is as large or larger than Kissing Bugs and shape and coloring may be similar. If you see flanges (leaves) along the hind legs, the separation is easy, but not all Coreids actually have those.  The large ones feed on fruit and cactus pads, often in aggregations, usually during the day 

Some Assassin Bugs found in Arizona may resemble Kissing Bugs

 Remember that  
Kissing Bugs are Assassin Bugs, but not all Assassin Bugs are Kissing Bugs
Most Assassin Bugs are predators of other arthropods. Many Assassins look similar to Kissing Bugs. They can be of similar size and also share a similar color scheme of red on black. If you look closely, their heads are not cone shaped like those of the Kissing Bugs.  Hint: if a predatory Assassin Bug bites you it hurts very much. 
If a kissing Bug bites you, it's completely painless and usually goes unnoticed.
Itching welts and inflammations may appear later. The strength of the reaction is dependent  on the immune reaction of the victim. Over time, after repeated exposure,  hypersensitivity can be developed and a person becomes allergic. These allergic reactions can be severe.  

Photo by Tony Palmer
 Here is Triatoma rubida, our most common Kissing Bug, feeding on a Mediterranean Gecko. The reptile made no effort to avoid the painless bite.  The bug injects an anesthetic and an anticoagulant.
1 Macrocephalus dorannae; 2 Lophoscutus sp.; 3 Phymata sp.; 4 Pseudozelurus arizonicus; 5 Narvesus carolinensis; 6 Oncocephalus geniculatus; 7 Reduvius sonoraensis; 8 Rhiginia cinctiventris; 9 Triatoma protracta; 10 Triatoma recurva; 11 Triatoma indictiva, 12 Triatoma rubida, 12a Triatoma rubida nymph

We have 3 or 4 species of Kissing Bugs here, all in the genus Triatoma,  In Tucson proper you'll see most likely Triatoma rubida, In Madera Canyon T. protracta is quite common, T recurva I have found at Clear Creek in Yavapai Co. All are night active and come to lights. 

My blog should help you to better identify the bugs you find. To learn more about Chagas disease and the status of vector infection in AZ, I suggest the paper 'Infection of Kissing Bugs with Trypanosoma cruzi, Tucson, Arizona, USA'  by Carolina Reisenman  et al. 


  1. Most don't seem to have much color on them, not surprising I suppose if they hide by day.

    1. For some reason the ones in Texas, which I'm not showing here, are more colorful

  2. Please share comparison photos of a local kissing bug with that of a squash bug... I can't tell the difference... Robert John Hebert, Sierra Vista, AZ

    1. Go to the group of Leaf=footed bugs right under the Milkweed bugs. The one in the middle of the top row is the Squash Bug

  3. Margaret, I've seen two kissing bugs enter my home through the chimney at night. They find their way! Dan

  4. Thank you for taking the time to write this post. We have rural property near Kirkland, AZ where our family (4 kids) spend weeks at a time. I've re-read your article every time I've found a "true bug", and have been relieved each time to match it to one of your non kissing bug pictures. Kissing bugs have been giving me the paranoid heebie-geebies, especially since the assassin and leaf footed bugs I've been finding look so similar. Thanks for the balanced info and assurances and also the comparison pictures!

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  6. In the last couple days there has been a large hatch of bugs that looks similar to kissing bugs (Craycroft & Sunrise are). Any idea on what they might be? Inquiring minds want to know :) Thank you!

  7. I have a history of severe allergic reactions to what doctors thought were from kissing bugs. Just recently i have had severe swollen bites on my arms. The swelling was deforming my forearms. I was confused as to what could be the cause. Just last night i killed 3 kissing bugs that had fallen onto my white car when using the garage door. I immediately realized the severe bites of a few weeks ago correspond with the timing of cleaning out my garage. It was quite wet when i was working in the garage. I worked at night due to the heat and it was very wet due to a broken water heater. I thought these kissing bugs like dry areas. Pack rat dens etc. Finding more concerns me obviously. Any suggestions to deter them. I hate to use poison as i have animals and choose for myself to be chemical free. Im not into killing anything. This was situational. I dont normally have a wet garage filled with household items etc. I am however concerned for my health. Thanks for your blog.

  8. I'm finding kissing bugs in my apartment on golf links. I think they are entering through the AC and cracks . I'm thinking of breaking my lease. I have been getting what I thought was mosquito bites but while looking for the mosquito I found the bug on my foot also flea looking things on the window and a bee or large gnat today . Freaking out and only been in this place 5 days.

  9. To learn more about kissing bug research in Tucson, please visit our website: If you are interested in being apart of our citizan science project, please visit the "Get Involved" tab.