Scolecids are mostly unselective deposit feeders on marine detritus.

The head has no appendages or palps and is usually conical, though in the Scalibregmatidae, it has a T-shaped tip, and in Paraonidae, there is a single, central antenna.

The oesophagus is evertable forming a sac-like proboscis which may have several finger-like lobes.

The notopodia and neuropodia consist of unbranched capillary chaetae, sometimes with hooks.

They are now included in infraclass Scolecida along with Cossuridae, Orbiniidae, Opheliidae, Paraonidae and Scalibregmatidae.