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Cyphomyrmex rimosus

Q:  I have found small brown insects in a tree stump in my yard.  Do I need to be concerned about them infesting my house?

A:  The insects you found are actually tiny ants, Cyphomyrmex rimosus.  These insects were so tiny I had to look at them under a stereoscope.  This was the first time I had seen this particular ant – they are quite menacing.  Colonies can be polygamous, which means they have more than one queen.  Workers forage on the surface of the ground, harvesting small insect parts and caterpillar droppings to use as substrate for fungal gardens.  This is a good time to discuss the importance of insects.  All ants are not the invasive fire ant which gives us so many problems.  In fact, very few insects cause problems to humans but unfortunately all the insects take a bad rap for the minute number of trouble makers.  That seems to be true with humans too – sorry I digress.  These insects play an important role by aiding in the decomposition of dead insects.  It is important that we take a “live and let live” attitude so the good guys aren’t killed along with the bad insects.  C. rimosus is the most abundant species in open areas, replaced in abundance by C. salvini in wet forest habitats. Nests are in the soil, under stones, or under dead wood on the ground.  So, to answer your question – you do not need to worry about this insect, in fact we would classify it as a beneficial.