1. The eon following the Hadean time and preceding the Phanerozoic eon; from about 3,800 million years ago until 544 million years ago
   - Precambrian, Precambrian eon, Precambrian period

Type of: aeon, eon

• genus Punica
• genus Pycnanthemum
• genus Pygopus
• genus Pygoscelis
• genus Pylodictus
• genus Pyracantha
• genus Pyralis
• genus Pyrausta
• genus Pyrethrum
• genus Pyrocephalus
• genus Pyrola
• genus Pyrophorus
• genus Pyrrhula
• genus Pyrrhuloxia
• genus Pyrrosia
• genus Pyrularia
• genus Pyrus
• genus Pythium
• genus Python
• genus Pyxidanthera
• genus Quamassia
• genus Quassia
• genus Quercus
• genus Quiscalus
• genus Rachycentron