How do oligochaetes differ from polychaetes?

Small bristle worms (representative – earthworm) belong to oligochaetes, and polychaetes (representatives – aphrodite, nereid) belong to polychaetes.
Differences:
– the number of species. There are about 3 thousand species of small-bristled worms, and about 10 thousand of polychaete worms;
– exist in different habitats. Small bristle worms live mainly in the ground, and most polychaete worms live in salty and warm water bodies;
– the size. Oligochaetes are larger than polychaetes;
– the way of breathing. Polychaetal worms breathe with the help of pseudogill – bristles, and polychaete worms absorb oxygen from the entire surface of the skin;
– breeding method. Oligochaetes are hermaphrodites, emerge from the egg and are similar to their parents, polychaetes are dioecious, go through the larval stage;
– The presence of outgrowths – parapodia – is the main difference. Parapodia are characteristic of polychaete worms.