Thelepus cincinnatus is a species of polychaete annelids in the family Terebellidae (spaghetti worms), which can be found inhabiting a tube of secrete on rocks and shells.

The worm is widely distributed, and can be found in almost any region of the oceans at depths ranging from 10 to 4000 meters.

[1] Anteriorly, T. cincinnatus has several long feeding tentacles and two pairs of filiform branchia.

The number of body segments is not predetermined but can exceed 100 while the total length of the animal can reach 200 mm.

[2] Thelepus cincinnatus inhabits many kinds of benthic environments ranging from mud to rocks, where it constructs a tube made by secretions, which it attaches to a substrate.