Ampyxina bellatula By Matt Young April 17, 2017 11:00 MST Photograph by James Kocher. Photography Contest, Honorable Mention. Ampyxina bellatula (Ullrich, 1922) – trilobite, ~475 Ma, Maquoketa Shale, Late Ordovician. Gailey Branch Creek, McCune Twp., Pike County, Missouri.