Unrelated, but I have seen 3 or 4 morphologically distinct species of Tapinoma (in size, behaviour) distinguishable from the queens here in Ontario
To my knowledge there is only one Tapinoma endemic to your area, T. sessile, and to date only 3 confirmed and recognized species of Tapinoma to the continental US and Canada: T. sessile, T. schreiberi, and T. litorale. There is I will note though that most likely within the next 6 months a published work will come out describing new parasitic Tapinoma species found in the Eastern US (this from private communication with ant expert at Harvard).
Quite a bit of morphological variation within T. sessile often leads to false reads regarding novel species claims. The only way I feel at the current moment and as my own research is indicating is to get proper measurements: Head Length, Head Width, Scape etc and run the numbers, or to do a genetic test. My examination of only CO1 sequences from Canadian samples, a vast number being from Ontaria indicates that the Canadian population of Tapinoma sessile all fall within the "Mountain" clade, most likely a cold/elevation adaptive subpopulation, as per this published paper's analysis: https://journals.plo...al.pone.0009194.
If you want to collect samples and send them to me of what you feel are possibly new ants please feel free. You may contact me via private chat.