PORT PHILLIP BAY


Ragworm 

Perinereis amblyodonta (Schmarda, 1861)

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. Maxillary ring of pharynx with 2-5 conical paragnaths on Area I; II: 11-28; III: 14-36; IV: 18-63 . Area V: 1-3; VI a single bar-shaped paragnath on each side; VII-VIII: 33-50 conical paragnaths. Dorsal notopodial ligule 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 2 times ventral notopodial ligule at chaetiger 10-20. Neuropodial postchaetal lobe present, at least on some anterior chaetigers. Ventral neuropodial ligule on posterior chaetigers similar to 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:
Perinereis
Species:
amblyodonta

General Description

In members of this genus there are bar-shaped paragnaths on the dorsal part of the eversible pharynx (Area VI); elsewhere there are conical paragnaths on most other regions of the pharynx. The dorsal bunch of chaetae are long-bladed spinigers throughout all segments. This species can be distinguished readily by paragnath counts on Area VI of the eversible pharynx. Only 3 species of Perinereis are common in southern Australia: P. amblyodonta has a single bar-shaped paragnath on each side of Area VI; P. variodentata has two bar-shaped paragnaths on each side of Area VI; P. vallata has an arc of 5-14 bar-shaped paragnath on each side of Area VI. Body up to about 8-10 cm long.

Biology

Only 3 species of Perinereis worms are common in southern Australia.

Habitat

Rocky shores on sheltered and (especially) exposed coasts; intertidal, occasionally to depth of about 10 m.

Reefs

Coastal shores

Distribution guide

South-eastern Australia, or south-western Australia, or north-eastern Australia, or north-western Australia.

Species Group

Worms › Ragworms

Depth

Shore (0-1 m)

Water Column

On or near sea floor

Max Size

10 cm

Commercial Species

No

Species Code

MoV 2597

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, Perinereis amblyodonta, in Taxonomic Toolkit for marine life of Port Phillip Bay, Museum Victoria, accessed 01 Dec 2024, http://136.154.202.208:8098/species/7568

Text: creative commons cc by licence