Aeolosoma is a genus of minute annelid worms, variously attributed either to oligochaetes or polychaetes.

[2] Unlike most polychaetes, they reside in freshwater environments in various parts of the world.

[4] This is done by paratomy (fragmentation), when the posterior segments are separated from the parent worm.

It starts when the worm reaches a certain number of millimeters (depending on the species).

[7] Their mouth acts like a small vacuum cleaner, which helps them suck up their food into their system.