False Chinch (or Cinch) Bugs

False chinch bugs, also sometimes known as "false cinch bugs" are little insects that will sometimes appear in swarms in Tucson. After a wet, warm winter the juvenile "false chinch bugs" can appear. The swarms are usually described as a weird brown mass that keeps changing shape and moving.

The "false chinch bugs" will migrate in huge clouds and settle in shady areas. These insect swarms are not harmful but if you step on these insects they will emit a stinkbug aroma. These insects do not bite or spread disease. The masses of these insects will be around for two to three weeks. You do not need to spray these insects. They will not harm humans, pets or yard plants.

To control these insects around your home:

  • Close your doors and windows.
  • Vacuum insects that get inside your house.
  • Swarms outdoors can be sprayed with a hose.

For more about false chinch bugs, including photos, see University of California Statewide Integrated Pest Management Program False Chinch Bug, opens a new window and Maricopa County Cooperative Extension False Chinch Bugs in the Low Desert, opens a new window.


“Clouds of odd bugs invade.” Arizona Daily Star. May 10, 2005. Page B1.

Werner, Floyd G.  Insects of the Southwest: how to identify helpful, harmful, and venomous insects. Tucson, AZ: Fisher Books. c1994. Page 108.

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