Marine Worm

Scientific nameSketch of the marine worm. Illustration by Pat Hutchings, Australian Museum.

Hadrachaeta aspeta

Status in NSW

Presumed extinct.


Hadrachaeta aspeta is a species of tube-dwelling bristle worm. It is the only species in its genus and is endemic to eastern Australia.

It has numerous thick, grooved tentacles and three pairs of gills on segments 2 - 4 of the body. It has a compact protomium (first body segment) with thickened, out-folded lips and no eye spots.


Hadrachaeta aspeta is a small species growing to a maximum length of approximately 25 mm.


The only published records of Hadrachaeta aspeta are from Patonga Creek (lower Hawkesbury River) and Yamba in New South Wales, and from Serpentine Creek (Brisbane) in Queensland. There have been no records in NSW for over 30 years despite targeted surveys, and the species is now considered extinct in NSW.


It lives in soft muddy sediments in the inter-tidal zone of enclosed bays and estuaries on the seaward side of mangroves.

Why did Hadrachaeta aspeta become extinct?

The cause of extinction of Hadrachaeta aspeta is not definitively known, however a range of factors are thought to have contributed including:

  • Pollution caused by antifouling paints in enclosed waters.
  • Accumulation of toxins in sediments in enclosed waters.
  • Habitat degradation through changes in environmental conditions over the last century.

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