Pennsylvania Statutes Title 71 P.S. State Government § 1010.3. Official state fossil

Phacops rana is a specific type of trilobite, a small sea creature. Trilobites were rulers of the sea during the Cambrian Period, 515 to 600 million years ago. Trilobites are so named because their bodies are divided lengthwise into three parts or “lobes.” Phacops rana means “frog eyes” because of the large holes for eyes on the fossil. Fossils of Phacops rana are found in many parts of Pennsylvania, and, therefore, the Phacops rana is selected, designated and adopted as the official State fossil of the Commonwealth of Pennsylvania.