I found this in my usual rip rap spot, which has a maddening mix of formations (from Bois Blanc, Amherstburg, Dundee, and even some Hamilton Gp formations, too - yargh).
My first instinct with this one was Anchiops anchiopsis, but there is something not quite right about this one. It is tough to make out if there is a pygidial spike for one, I cannot make out any incised axial rings, and it does not have the same acute angle of pleural tapering I usually see with this species. There appears to be a border on the lower left of the pygidium, and the pleura seem to stretch out quite widely while the axial part is quite thin (reminiscent of Coronura aspectans).
Is this something else, or just another Anchiops that is simply freakish?
I made a minor attempt to reveal more of it. Trilobites in this matrix do not preserve particularly well.