Aeolosoma

Aeolosoma usually reproduce asexually. This is done by paratomy or Fragmentation (reproduction), 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). Only one species, Aeolosoma singulare, is known to reproduce sexually.

Aeolosoma feed on microalgae, microorganisms and detritus. Their mouth acts like a small vacuum cleaner, which helps them suck up their food into their system.

Morphology

Aeolosoma are transparent worms, very thin and of the length of 1.5–2 millimetres, although some can reach up to 5 millimetres. Their bodies are transparent and segmented, usually comprising around 17 segments. Each segment, except for the first, consists of bundles of bristle-like structures known as setae or chaetae, which aid in locomotion.

The Prostomium (head region) is broader than the subsequent segments and is equipped with ventral cilia that facilitate movement and feeding, Notably, Aeolosoma lacks appendages on the head and parapodia (lateral outgrowths) found in some other annelids. The integument contains pigmented epidermal glands filled with coloured oil droplets, which can be red, yellow, green, or occasionally colourless, giving the worms a distinctive hue.

Aeolosoma exhibits a high capacity for regeneration, with some species capable of regrowing both anterior and posterior segments within a week after amputation.