Sphaerocoryphe cf. arachniformis

This is a Sphaerocoryphe cf. arachniformis from the Galena Formation of Southeast Minnesota. The "cf." in this case means that it is similar to but may be different. This trilobite has not been officially described out of the Galena Formation, but it is similar in age and appearance to S. arachniformis which is described out of the Kimmswick Formation of Missouri. In the upper left of the photo is a Porocrinus sp.