The ampharetids resemble the terebellids in many structures and were included among the terebellids until Malmgren's 1866 revision. Ampharetids can retract or withdraw their buccal tentacles completely within their mouth (retraction is done as a whole unit, not by individual tentacular retraction), whereas, terebellids and trichobranchids cannot. Additionally, ampharetids usually have a few pairs of simple branchiae, never the masses of aborescent branchiae or numerous sessile filaments in the terebellids. Also the uncini are flattened plates in the ampharetids, not nearly always crested as in the terebellids.

For the coding of the world genera in the interactive key we have followed Fauchald (1977) plus Holthe (1986b) for the more recent genera, but it is generally recognised that a world generic revision is urgently needed. It may subsequently be found that not all the 76 genera are valid. 45 genera in the world are monotypic, many of which apppear to be known only from the original record and often representing a single individual, as well as being from very deep waters in many cases. Many of these monotypic genera are incompletely described and poorly illustrated in the original description, and as they have not been recorded since, this database has only coded and illustrated as best we can.

This interactive key includes all the 75 genera in the world, divided into 2 subfamilies - Ampharetinae with 66 genera, and Melinninae with 9 genera. Australian waters have 12 genera recorded, as well as 1 new undescribed genus (Hutchings & Peart, in prep). All known Australian species included in this database (7 species, representing 6 genera) are based on published descriptions. The principal areas surveyed are Bass Strait and Port Phillip Bay (material held in Museum Victoria, Melbourne) and Jervis and Botany Bays (material held in Australian Museum, Sydney). Many taxa undoubtedly remain to be described from Australian waters, especially beyond the soft sediment communities of southeastern Australia which have generated much of the material covered here. Little sampling on the Australian continental shelf and beyond has occurred, and it is suspected that a rich and diverse ampharetid fauna remains to be described.