There are three main classifications of earthworms:
1. Epigeic earthworms: These are the surface-dwelling earthworms that live in leaf litter and other organic matter. They are usually smaller in size and have lighter pigmentation than other types of earthworms.
2. Endogeic earthworms: These are the earthworms that live in the soil and are commonly found in agricultural fields and other disturbed soils. They make horizontal burrows in the soil and feed on organic matter that is mixed with the soil.
3. Anecic earthworms: These are the largest earthworms that live in vertical burrows and can be found deep in the soil. They feed on surface plant material that is brought into their burrows and can be important for soil aeration and drainage.