PORT PHILLIP BAY


Phyllodocid worm 

Mysta platycephala (Augener, 1913)

View scientific description and taxonomy

Scientific Details

Family level description.
Phyllodocidae are long-bodied predators in which the dorsal cirri are distinctly leaf-like and form long regular rows along each side of the body. They are often strongly pigmented in green or yellow. There is a short ovoid prostomium with two pairs of short anterior appendages (1 pair of palps; 1 pair of antennae); a single median antenna may also be present. The long eversible pharynx lacks jaws or other hard parts but typically has numerous papillae in various distinctive arrangements. Compound long-bladed chaetae are typical, in ventral positions.

Species level technical description.
Eyes deeply sunken. Prostomium without dorsal posterior incision. Dorsal paired antennae broadest basally. Prostomial protuberance indistinct. Nuchal organs present as ciliated pits. Nuchal organs and cirrophores of first pair of tentacular cirri separate basally. Median antenna present as a papilla. Pharynx not divided into 2 regions. Pharyngeal papillae absent or large, conical to rounded (proboscis may be rugose), papillae on undivided pharynx with a single lateral longitudinal row on each side. Anterior segments all distinct (i.e. one pair or two pairs (dorsal and ventral) of tentacular cirri present on each segment). Segment 1 and 2 not covering posterior part of prostomium, segment 1 with two pairs of tentacular cirri arising from the first visible segment after the prostomium. Segment 2 lacking dorsal tentacular cirri. Ventral tentacular cirri of segment 2 circular in cross-section. Segment 3 lacking dorsal cirri, with ventral cirri. Chaetae first present on segment 2 or 3. Segments 2-4 lacking specialised enlarged chaetae. Parapodia uniramous (notopodial aciculae absent), Notopodial capillary chaetae absent. Neuropodium of median segments with separate dorsal and ventral prechaetal lobes, dorsal part of neuropodial lobe of median segments rounded and similar in shape to ventral lobe. Ventral cirri of median segments horizontally oriented.

Taxonomy

Phylum:
Annelida
Class:
Polychaeta
Order:
Phyllodocida
Family:
Phyllodocidae
Genus:
Mysta
Species:
platycephala

General Description

In members of this genus the tentacular cirri are fewer than in other Phyllodocidae, only 3 pairs in total, and the eversible pharynx has a distinctive row of large flattened papillae on each side. A median antenna is absent. Body up to about 5 cm long.

Biology

This species has generally only been collected on subtidal sandy sediments.

Habitat

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

Soft substrates

Distribution guide

Southern Australia.

Species Group

Worms Phyllodocid worms

Depth

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 1178

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, Phyllodocid worm, Mysta platycephala, in Taxonomic Toolkit for marine life of Port Phillip Bay, Museum Victoria, accessed 21 Sep 2017, http://portphillipmarinelife.net.au:8098/species/7535

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