👉 Annelids are a class of invertebrate animals that include a wide range of creatures, including worms, slugs, snails, and insects. They have a single, hard exoskeleton made up of a tough outer layer called the exostium or shell and a soft inner layer called the mantle. The annelid family includes many different species of animal, with some being known for their complex digestive systems and ability to feed on organic matter.
Annelids are important in the
annelida