PORT PHILLIP BAY


Ragworm 

Platynereis antipoda Hartman, 1954

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.
Paragnaths are generally present in most areas of the eversible pharynx and they form distinctive comb-like rows (sometimes quite faint). Notochaetae are spinigers only anteriorly, but long-bladed chaetae with distinctive articulation ("homogomph") in the dorsal bundle of chaetae occur after about segment 15. Simple chaetae with fused articulation are absent.

Taxonomy

Phylum:
Annelida
Class:
Polychaeta
Order:
Phyllodocida
Family:
Nereididae
Genus:
Platynereis
Species:
antipoda

General Description

In members of this genus the pharynx has very fine paragnaths in distnictive comb-like rows. Although a compound microscope is required, there are also long-bladed chaetae with a distinctive ball-and-socket articulation and a terminal tendon present in the dorsal bundle of chaetae on most segments starting at about segment 15-20 (these are referred to as "homogomph falcigers" in technical diagnoses). This species can be distinguished in southern waters by knowing that Platynereis antipoda is the only known species. It is quickly recognised from other Nereididae species that may be in the same samples by the distinctly short and stubby appearance of the first 4 pairs of parapodia (feet); this is especially evident when viewed ventrally. The tentacular cirri also tend to be much longer than in other local Nereididae. Body up to about 6-8 cm long.

Biology

This is one of the most common polychaete species in shallow reef areas in southern Australia. It seems able to adopt the colour of the substrate it lives on: when living among green algae it is frequently green in pigment while specimens collected from red algae will usually be red.

Habitat

Rock and seagrass areas, wherever algae are present; intertidal to depth of about 20 m.

Reefs

Seagrass meadows

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)
Shallow (1-30 m)

Water Column

On or near sea floor

Max Size

8 cm

Commercial Species

No

Species Code

MoV 4234

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, Platynereis antipoda, in Taxonomic Toolkit for marine life of Port Phillip Bay, Museum Victoria, accessed 29 May 2017, http://portphillipmarinelife.net.au:8098/species/7584

Text: creative commons cc by licence