Research Grade species #1190
Odorous house ant Tapinoma sessile
This little spring Tapinoma sessile worker shared the side stoop with me as I sat on a warm early spring day. Her colony's primary food source, the honeydew from aphids and planthoppers, is in short supply. Fortunately this North American species has done quite well with the spread of sugar-addicted humans and will come indoors to enjoy sweet crumbs and sticky spills. When someone crushes this ant, there is an odor of (depending on who is reporting) cocoanut, bleu cheese, or kerosene, earning it the regrettable common name "odorous house ant." This species is subordinate to other house-dwelling ants, like the immigrant pavement ant (Tetramorium immigrans) in the east, or the Argentine ant (Linepithema humile) in the west, and lets these aggressive invaders eat first.
Argentine ant Linepithema humile
Immigrant pavement ant Tetramorium immigrans