Definition: Antiperitites are ancient, fossilized plant remains found in Antarctica. They are believed to have originated from the earth hundreds of millions of years ago when rainwater collected on a glacier during a time of great ice melt. Definition: Antiperitites are fossils that are found in the Earth's crust or on the surface of Mars and other asteroids. They contain evidence of life billions of years old, including traces of plants and animals. Antiperitites have been found in various locations around the world, ranging from Antarctica to the Moon.