[Solved] How are the id, the ego, and the superego interrelated? Phylum: A phylum is a classification level in biological taxonomy that is below kingdom and above class, used to group together organisms that share a basic body plan. Rhyniophyta: An extinct group of early vascular plants from the Silurian and Devonian periods. Megafossils: Larger fossilized remains of organisms, such as bones or plant stems, that are easily visible to the naked eye and provide significant evidence of life from the past. Dichotomously Branched: A branching pattern where each branch divides into two parts at a certain point.