PORT PHILLIP BAY


Tube Worm 

Hydroides brachyacanthus Rioja, 1941

View scientific description and taxonomy

Scientific Details

Family level description.
Serpulidae are tube-dwelling polychaetes which build and live within calcareous tubes. Apart from one genus of tropical Sabellidae, these are the only polychaete family to construct calcareous tubes, which may be solitary, or in dense aggregations. In almost all serpulids there are 7 thoracic segments bearing chaetae, plus a variable number of abdominal segments. A radiolar crown of feeding tentacles is present, and nearly all serpulids have one tentacle modified to form a variably ornamented operculum which closes the tube when the worm retracts within.

Species level technical description.
Tube: white and brittle; keels not always conspicuous; tube usually completely attached to substrate. Pseudoperculum or rudimentary operculum present. Operculum present, carried on a modified non-pinnulate stalk, circular, sub-triangular or oval in cross-section, smooth. Operculum funnel-shaped, two-tiered funnel, dentate margin (radii distally pointed), 24-31 radii on margin. Ornamentation of operculum present (with protuberances projecting from top of operculum), smooth spines, 7-11 spines, spines curve inwards; internal spinules absent; 1 or more spine(s) larger than others. 12 pairs of branchial radioles. Pinnule-free tips of the branchial radioles present. Branchial interradiolar membrane absent. Branchial crown radioles arranged in 2 (semi)circles. Long pinnule-free tip. Collar chaetae present, capillary or with dentate boss or processes sub-terminally (bayonet-shaped); bayonet-shaped chaetae with 2 conical processes at base. 7 thoracic chaetigers. Thoracic membrane present, not connected dorsally. Thoracic sickle notochaetae absent. Abdominal chaetae trumpet-shaped, with flat or only slightly rounded distal margin; flat trumpet-shaped chaetae. Thoracic uncini with few teeth, 5-7 teeth. Thoracic uncini with 1 vertical row of teeth. Anterior abdominal uncini with 1 vertical row of teeth.

Taxonomy

Phylum:
Annelida
Class:
Polychaeta
Order:
Sabellida
Family:
Serpulidae
Subfamily:
Serpulinae
Genus:
Hydroides
Species:
brachyacanthus

General Description

In members of this genus the tube may have longitudinal ridges. The operculum has two tiers, a basal funnel of rused radii and a distal crown of chitinized spines. Interradiolar membrane generally absent. In this species the spines on the operculum are smooth.

Biology

This is one of several Hydroides species commonly found on ship hulls and has probably thus been transported around the world.

Habitat

Hard substrates such as intertidal rocks, to depth of 5 m.

Reefs

Coastal shores

Distribution guide

Eastern Australia.

Species Group

Worms Tube worms

Depth

Shore (0-1 m)
Shallow (1-30 m)

Water Column

On or near sea floor

Max Size

Diet

Organic matter

Commercial Species

No

Global Dispersal

Recorded in Australia

Species Code

MoV 3347

Identify

Conservation Status

  • DSE Advisory List : Not listed
  • EPBC Act 1999 : Not listed
  • IUCN Red List : Not listed

Author

article author Wilson, R.

Robin Wilson is a Senior Curator of marine invertebrates at Museum Victoria.

citation

Cite this page as:
Wilson, R., 2011, Tube Worm, Hydroides brachyacanthus, in Taxonomic Toolkit for marine life of Port Phillip Bay, Museum Victoria, accessed 29 May 2017, http://portphillipmarinelife.net.au:8098/species/11176

Text: creative commons cc by licence