Annelid Worms

A polychaete fanworm

Marine annelid worms vary a great deal from the garden varieties with which we are familiar. They belong to the phylum Annelida, a Latin word meaning 'little ring.' Annelids also belong to the Class Polychaeta, from the Greek word meaning 'many long hairs.'

They are characterised by:

• A worm shape
• Segmented body
• A distinct head, bearing eyes and tentacles - which is reduced in tube-dwelling forms
• Most segments have appendanges, bearing bundles of bristles

Worms play an important role in the breakdown of corals. In a research program conducted at Heron Island, a dead coral colony weighing over three kilograms was broken open, and the animals inside analysed. More than two thirds of the organisms collected were worms - 1441 individual worms representing 103 different species.