Partial Shield of Anoria tontoensis (IMAGE) Utah State University Caption Trilobite fossil from Grand Canyon's Bright Angel Formation. Partial shield of Anoria tontoensis Walcott, 1916b [DMNH 42917] from the Glossopleura walcotti Biozone, lower Flour Sack Member, Bright Angel Formation, Diamond Bar Ranch Arizona from FHPR loc. 006-5. Credit Frederick Sundberg, UNM Usage Restrictions Credit author License Original content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.