Fairy Ring?

Well in the worst case scenario, we'd only have to wait a couple of months to observe the mushroom from many angles! :)

That's it! Completely overlooked the one on the far left from this spotting's thumbnail, but here's the culprit. Any chance you could visit this site again when the mushrooms fruit?

here is an cousin of the other spotting, and i suspect these are all the same species: just young and old. For a fairy ring: has 1 species of mushroom stand in a ring,!! it should not count if it were 2 different species as half-circle-against each other,again 1 complet ring forming. But after seeing this picture: i will suggest: 3 genas ---> Agrocybe, Agaricus or least-likely psathyrella !! For the species, please try a local fungi site with those genas. good luck