Tiny Bugs in Montana might be Dirt Colored Seed Bugs or False Chinch Bugs

Subject: Tiny beetles (?) in Montana
Location: Near Gardiner Montana
November 12, 2012 2:46 pm
On August 5, 2005 I came upon this ground swarm of tiny bugs, about the size of sesame seeds or a little larger. They were racing across the ground like swarming ants; some were grouped together in clumps. They did not fly.
This is an area of foothills at an elevation of about 5500 feet near Gardiner Montana at the north entrance to Yellowstone Park. Vegetation was grass and greasewood and scattered prickly pear cactus. I’ll include two photos of the bugs, plus one photo showing the area where they were. I have a video of them racing across the ground but it doesn’t look like I can post a video.
Signature: Randy

True Bugs

Hi Randy,
We will work on this ID as soon as we finish planting onions and sugar snap peas before the sun goes down.  These are not beetles.  They are True Bugs.  They resemble Chinch Bugs.

Gardiner Montana a mile high

Ed. Note:  A short while later.
We really love that you have shown a photo of the habitat.  That might turn out to be especially significant.

Numerous Small Bugs

We are wondering if these might be some species of Dirt Colored Seed Bug in the family Rhyparochromidae.

Eric Eaton agrees.
They are all nymphs, so I don’t know that they can be easily placed…..Dirt-colored seed bugs would be my first thought as well, but I just can’t be totally positive.

Randy Responds
I don’t see a way to respond to your answer on the website.  But I did some googling after reading your response.  It’s pretty clear these are False Chinch Bugs.  Do a google image search for False Chinch Bugs and you’ll see these.  Apparently mine are in the nymph stage.  One website explains they often feed on plant seeds in the mustard family… one of my pics coincidentally shows a dried seedstalk (laying horizontally) of a pepper grass plant — in the mustard family.  Very cool.  THANK YOU!!  -Randy

Ed. Note:  November 14, 2012
Despite Randy’s confidence that these little nymphs are False Chinch Bugs, we side with Eric because nymphs can be so difficult to identify.  It can be extremely difficult to identify Hemipteran nymphs with any accuracy from a photograph, especially when there are no adults present.  The remote location of this sighting might mean this is a native species with a very localized distribution. 

Update:  October 7, 2013
We are wondering if these might be immature
Rhyparochromus vulgaris, a recent introduction to the Pacific Northwest.

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