Mosquito worm 

Exogoninae sp. MoV 597

View scientific description and taxonomy

Scientific Details

Family level description.
Syllidae are extremely common and diverse marine worms which have no common name but might easily be termed "mosquito worms" since their primary adaptation is to have mouthparts comprising a single piercing tooth (trepan) and a muscular gizzard (proventriculus) which are used to pierce and suck out the contents of hydroids, bryozoans and other encrusting prey organisms. The proventriculus has regular transverse bands and is often visible through the body wall and serves to immediately recognise members of the family. The prostomium has a pair of palps and a pair of antennae, sometimes with an additional median antenna. Chaetae often include short-bladed compound forms with a distinctly bidentate tip.

Species level technical description.
Adult size small, Usually less than 10mm in length. Reproduction method epigamous reproduction. Palps fused for at least half their lengths, but not completely or palps completely fused (or at most with terminal cleft or dorsal crease), longer than prostomium. Antennae present, slender and cirriform or pyriform (broad bulbous base and tapered tip, pear- or flask-shaped) or globular, smooth, or at most, wrinkled. Tentacular cirri present or absent, one pair or two pairs. Eversible pharynx straight or folded, unarmed or with tooth/teeth, with single large mid-dorsal tooth; Anterior margin of smooth (sometimes with soft papillae). Nuchal organs as small projecting lobes, or inconspicuous. Occipital flap absent. Segmental ciliary bands absent. Dorsal cirri present on all chaetigers or present on all chaetigers except chaetiger 2. Ventral cirri present. Bayonet-shaped simple chaetae absent.



General Description

In members of this subfamily the palps are fused and a single pair of tentacular cirri is present. Body up to about 1 cm long.


There are at least 100 species of Syllidae known from Australia and taxonomists are currently describing more species. Most species will require observation of chaetal structures at high magnifications before their identity can be confirmed. The subfamily Exogoninae comprise many very species and although found in many environments, they are especially prevalent in soft sediments.


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

Soft substrates

Distribution guide

Southern Australia.

Species Group

Worms Mosquito worms


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

Water Column

On or near sea floor

Max Size

1 cm



Commercial Species


Global Dispersal

Native to Australia

Species Code

sp. MoV 597


Conservation Status

  • DSE Advisory List : Not listed
  • EPBC Act 1999 : Not listed
  • IUCN Red List : Not listed


article author Wilson, R.

Robin Wilson is a Senior Curator of marine invertebrates at Museum Victoria.


Cite this page as:
Wilson, R., 2011, Mosquito worm, Exogoninae , in Taxonomic Toolkit for marine life of Port Phillip Bay, Museum Victoria, accessed 15 Apr 2024,

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