OFFICIAL STATE FOSSIL - PHACOPS RANA Act of Dec. 5, 1988, P.L. 1113, No. 138 Cl. 71 AN ACT Designating the Phacops rana, a trilobite, as the official State fossil of the Commonwealth of Pennsylvania. The General Assembly of the Commonwealth of Pennsylvania hereby enacts as follows: Section 1. 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. Section 2. Effective date. This act shall take effect immediately.