This is a fabulous Bumastus ioxus from the Rochester Shale of New York. This distinct trilobite is EXTREMELY 3-dimensional, very prone, and nicely articulated - both free cheeks are even intact. The dark trilobite contrasts beautifully with the grey matrix. The bug is very well showcased on the plate of dense shale that also contains a Bumastux cephalon. And at a full one and a half inches long, it is quite large for a Bumastus from this site. This is a top quality example of this classic Silurian trilobite, Bumastus ioxus.