Members of the Class Oligochaeta include earthworms and many freshwater
forms
Oligochaetes are the simplest annelids. They do not have parapods as
happens in polichaetes, and have few setae (spine-like appendages; oligo="few",
chaeta="setae"). The setae are the spine-like hairs extending
from the body. Members of this class also possess a reproductive structure
called the clitellum (a reproductive structure)
The most common example of an oligochaete worm
is the earthworm, Lumbricus terrestris.
These small animals perform an important function
in ecosystem since they keep soils aerated, and their castings fertilize
the soil.
){kind=link}