Lagis australis: Difference between revisions

Pectinaria australis is a polychaete worm of the family Pectinariidae, endemic to New Zealand where it is the only pectinariid species.

It is found both intertidally on sheltered sandy shores, and at depths of up to 70 metres, buried obliquely head-down in the substrate with only the tip of the cemented sand grain cone visible. The cone is up to 50 mm long.

Pectinaria australis builds its delicate tube out of a thin layer of sand grains cemented by secretions of the worm's body. The tube is built with exquisite care, each sand grain being selected and cemented in place to a thickness of only one sand grain.

Populations tend to be aggregated, and sporadic from year to year, with adults densest just subtidally in shallow harbours. Density may increase around sources of organic pollution and in eelgrass beds, but Pectinaria australis is also found in clean sand where population density is likely to be less than 50 per square metre. The life cycle is short, approximately one to two years.

When handled Pectinaria australis produce a copious clear mucus, perhaps as a defense strategy.

• Annelida.net
• Miller M & Batt G, Reef and Beach Life of New Zealand, William Collins (New Zealand) Ltd, Auckland, New Zealand 1973