PORT PHILLIP BAY


Nephtyid worm 

Nephtys inornata Rainer & Hutchings, 1977

View scientific description and taxonomy

Scientific Details

Family level description.
Nephtyidae are active predators with very muscular body that is distinctly rectangular in cross-section with corners formed by parapodial lobes and often long chaetae. The prostomium has the form of a short truncate triangle with 4 small terminal appendages (1 pair of antennae, 1 pair of palps). The pharynx is eversible and typically has long papillae in rows and in a terminal ring; it lacks jaws or hard parts. A curved interramal cirrus occupies the space between dorsal and ventral lobes of the parapodia (feet).

Species level technical description.
Prostomium with antennae and palps; Not strongly produced anteriorly; lacking eyespots. Eyespots absent from anterior chaetigers, or present between chaetigers 2 and 3 (may be faint or apparently absent). Pharynx with bifid terminal papillae present, 18 papillae; Subterminal papillae present; Enlarged median subdistal dorsal papilla absent. Pharynx with 20 rows of subdistal papillae, each row made up of 4-7 papillae. Verrucae absent. Dorsal cirri present from chaetiger 1. Present on first chaetiger as short digitate papilla about 1/2 length of antenna. Dorsal interramal cirri absent, from chaetiger 5, cirriform, roughly circular in cross-section (ciliated), curve outward initially. Dorsal interramal cirrus without basal digitiform process. Ventral interramal cirri absent. Specialised dentate chaetae absent from notopodium of chaetiger 1. Barred chaetae present in preacicular fascicles. Lyrate chaetae absent. Spinose post-acicular chaetae absent. Spinulose post-acicular chaetae present. Capillary chaetae present.

Taxonomy

Phylum:
Annelida
Class:
Polychaeta
Order:
Phyllodocida
Family:
Nephtyidae
Genus:
Nephtys
Species:
inornata

General Description

In members of this genus the interramal cirri curve outward initially; lyrate chaetae are absent. Other species, and genera, of Nephtyidae occur in our region, but the two commonest species in Port Phillip Bay are Nephtys australiensis (with 20 terminal papillae on the pharynx and one enlarged midian papilla, interramal cirri from chaetiger 5) and Nephtys inornata (with 18 terminal papillae on the pharynx, no enlarged midian papilla, interramal cirri from chaetiger 4). Absence of spinose chaetae also distinguish this from most other species of Nephtys. Body up to about 5 cm long.

Biology

Other species, and genera, of Nephtyidae occur in our region, but the two commonest species in Port Phillip Bay are Nephtys australiensis and Nephtys inornata. Both species are active predators which live in soft sandy sediments; they do not form permanent burrows.

Habitat

Port Phillip Bay and other similar coastal habitats, inshore and continental shelf.

Soft substrates

Distribution guide

South-eastern Australia.

Species Group

Worms Nephtyid worms

Depth

Shore (0-1 m)
Shallow (1-30 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 399

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, Nephtyid worm, Nephtys inornata, in Taxonomic Toolkit for marine life of Port Phillip Bay, Museum Victoria, accessed 19 Oct 2017, http://portphillipmarinelife.net.au:8098/species/7544

Text: creative commons cc by licence