Jul 28, · Japan Mountain Leech vs. Giant Earthworm - Real Japan Monsters 日本マウンテンリーチ対ジャイアントミミズ 日本のモンスター - Duration: . Annelids are a phylum including earthworms, leeches, polychaete worms, and some other worm groups(3). Annelids are also called segmented worms because a defining feature they all share is a body most of which is divided into segments, each of which contains parts of the basic body systems (2). Segmented worms (Annelida) are a group of invertebrates that includes about 12, species of earthworms, ragworms, and leeches. Segmented worms live in marine habitats such as the intertidal zone and near hydrothermal vents. Segmented worms also inhabit freshwater aquatic habitats as well as moist.