Trilobites
Order Ptychopariida Suborder Ptychopariina, Superfamily
Ptychopariacea,
Family Alokistocaridae
Geologic Age: Middle Cambrian
Trilobite is 38 mm long
Spence Shale, Wellsville Mountain, Utah
Comment: Ogygopsis is an index fossil for the Middle Cambrian that is
found throughout Utah and Nevada.
