PORT PHILLIP BAY


Eunicid worm 

Eunice australis Quatrefages, 1865

View scientific description and taxonomy

Scientific Details

Family level description.
Eunicidae are common, widespread and diverse polychaetes characterised by having complex jaws of multiple pairs of maxillae and a pair of ventral mandibles; the anterior end has paired cushion-like structures (actually dorsal lips) and beaded prostomial appendages (antennae + palps) which may be 1, 3 or 5 in total number. Some have prominent comb-like gills on mid-body chaetigers. Dorsal chaetal bundles are absent; ventral bundles have capillaries, acicular hooks, compound hooks, and combs. These are robust, muscular, active, long-lived carnivores or scavengers found in a variety of habitats.

Species level technical description.
Prostomium bilobed, slightly to deeply notched, distinctly shorter than peristomium, about as wide as peristomium, at least as deep as 1/2 of peristomium. Prostomial lobes frontally rounded, dorsally flattened, median sulcus deep. Eyes present. Maxillary formula: I = 1, + 1. II = 6, + 6. III= 6, + 0 (Mx III long; located behind left Mx II). IV = 1, + 1. Number of prostomial appendages 5 - one median antenna and a pair of lateral antennae, plus a pair of palps (in lateral-most position). Prostomial appendages dissimilar in length. Median antenna longer than lateral antennae. Palps shorter than lateral antennae. Peristomial (tentacular) cirri present, reach middle or anterior end of peristomium, digitiform, articulated. Branchiae present, pectinate, distinctly longer than notopodial cirri, not reduced in mid-body region. Maximum number of branchial filaments 8, first reached in chaetiger number 10, 0 anterior chaetigers with single branchial filaments, 2 posterior chaetigers with single branchial filaments, stems erect. Branchiae from chaetiger 7, last present chaetiger 33. Pectinate chaetae present, on anterior segments distally flat, distally flaring, pectinate chaetae on median and posterior segments distally flat, distally flaring. Compound (composite) falcigers present, Appendages of compound falcigers distally bidentate, Hoods of compound falcigers distally without mucros (rounded). Pseudocompound falcigers absent. Compound spinigers absent. Aciculae light yellow or translucent, acicular cores and sheaths indistinctly separated, rounded in cross-section, distally pointed (sharp or blunt). Subacicular hooks present, light yellow or translucent, cores and sheaths indistinctly separated, tridentate, with teeth in a crest, first present from chaetiger 31, present in all chaetigers thereafter, always single (except for replacements).

Taxonomy

Phylum:
Annelida
Class:
Polychaeta
Order:
Eunicida
Family:
Eunicidae
Genus:
Eunice
Species:
australis

General Description

In members of this genus there are 5 prostomial appendages (antennae + palps) and one pair of tentacular cirri on the peristomial segment. Branchiae commence on chaetigers 3, 4 or 5, continue to about chaetiger 30 and have a maximum of 8 filaments each. Maxilla II has 6 teeth. Body up to about 5 cm long.

Biology

Common and widespread in shallow waters of southern Australia.

Habitat

Estuaries, embayments, continental shelf, sand, mud and weed beds, to depth of 80 m.

Seagrass meadows

Soft substrates

Reefs

Distribution guide

Southern Australia

Species Group

Worms Eunicid worms

Depth

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

Water Column

On or near sea floor

Max Size

5 cm

Diet

Carnivore

Commercial Species

No

Global Dispersal

Native to Australia

Species Code

MoV 4384

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, Eunicid worm, Eunice australis, in Taxonomic Toolkit for marine life of Port Phillip Bay, Museum Victoria, accessed 25 Mar 2017, http://portphillipmarinelife.net.au:8098/species/7462

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