Nephridia in earthworms are useful for performing functions like excretion and osmoregulation. Although the nephridia in earthworms are similar in structure they are classified into different types based on their location. They are classified as:

1. Septal Nephridia: It is located in both sides of the intersegmental septa from the 15^th segment till the end which has about 80-100 septal nephridia on a particular segment. They open into the intestines of the earthworm.

2. Pharyngeal Nephridia: It is located in the 4^th, 5^th and 6^th segment of the earthworm. The 6^th segment nephridia open into the buccal cavity while the 4^th and 5^th nephridia segment opens into the pharynx. The excretory matter is carried into the gut by these ducts.

3. Integumentary Nephridia: It is located in the body wall i.e., the integument of the earthworm. It is present on every segment of the earthworm and it is highly abundant in the clitellar region. These nephridia discharge the excretory products directly outside the body of the earthworm.