PORT PHILLIP BAY


Ragworm 

Neanthes bassi Wilson, 1984

View scientific description and taxonomy

Scientific Details

Family level description.
Nereididae are polychaetes with many uniform segments, without strongly differentiated body regions. The prostomium (head) has one pair of antennae, one pair of articulated palps, and two pairs of eyes. Four pairs of unjointed cirri emerge from the next segment behind the prostomium. Mouthparts comprise an eversible pharynx with one pair of terminal jaws, although these are usually only visible by dissection.

Species level technical description.
Prostomium with entire anterior margin. Longest tentacular cirri extend back to chaetiger 4-9. Area I conical paragnaths present 0-1; II: 6-27; III: 1-14 paragnaths; IV: 1-18 conical paragnaths plus 2-7 bars. Area V conical paragnaths 0-1 paragnaths; VI: 2-16 conical paragnaths; VII-VIII: 5-30; VII-VIII paragnaths differentiated into an anterior band of paragnaths similar in size to elsewhere on the proboscis, and a separate band of minute paragnaths (second row of small paragnaths posterior to row of large cones). Dorsal notopodial ligule not markedly elongate on posterior chaetigers. Not markedly broader on posterior chaetigers. Dorsal notopodial ligule not markedly reduced on posterior chaetigers. Prechaetal notopodial lobe absent. Dorsal cirrus not terminally attached to dorsal notopodial ligule on posterior chaetigers. Dorsal cirrus length about 1 times ventral notopodial ligule at chaetiger 10-20. Neuropodial postchaetal lobe present, at least on some anterior chaetigers. Ventral neuropodial ligule on posterior chaetigers reduced, up to half length of acicular neuropodial ligule. Ventral cirri single. Notopodial homogomph spinigers present. Notopodial homogomph falcigers absent. Neuropodial dorsal fascicle fused falcigers absent.

Taxonomy

Phylum:
Annelida
Class:
Polychaeta
Order:
Phyllodocida
Family:
Nereididae
Genus:
Neanthes
Species:
bassi

General Description

In members of this genus paragnaths are generally present in most areas of the eversible pharynx; Area VI has cones only (no bars, as are present in Perinereis spp). Notochaetae are only spinigers (short-bladed chaetae are absent from the dorsal bundle of chaetae, and simple chaetae with fused articulation are absent ventrally). This species can be distinguished by Area VII-VIII paragnaths 5-30 and generally comprise a mixture of large and small paragnaths; paragnaths on Area IV include a conspicuous triangle of bars; a prechaetal notopodial lobe is present. Body up to about 3 cm long.

Habitat

Coastal bays and continental shelf areas, to depth of about 50 m.

Seagrass meadows

Soft substrates

Distribution guide

South-eastern Australia, or south-western Australia.

Species Group

Worms Ragworms

Depth

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

Water Column

On or near sea floor

Max Size

3 cm

Commercial Species

No

Species Code

MoV 1065

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, Ragworm, Neanthes bassi, in Taxonomic Toolkit for marine life of Port Phillip Bay, Museum Victoria, accessed 26 Jul 2017, http://portphillipmarinelife.net.au:8098/species/7537

Text: creative commons cc by licence