PORT PHILLIP BAY


Hydroid 

Thyroscyphus marginatus (Bale, 1884)

View scientific description and taxonomy

Scientific Details

Family level detail.
Colonies, branched or unbranched, monosiphonic, hydrothecae free of stem on a short stalk (pedicel), margin of hydrotheca with three or four cusps, operculum pyramidal, gonothecae ovoid, borne on stem. The family Thyroscyphidae has only a few species the majority being large colonies found in tropical waters. The two temperate water southern Australian species are small and cryptic.

Species identification.
Stems small unbranched, usually with three or four hydrothecae, one on each stem internode. Hydrotheca large, campanulate, on a short pedicel, margin thickened with four equidistant low cusps. Gonotheca unknown. Colour: yellowish pink. Up to 1 cm long.

Taxonomy

Phylum:
Cnidaria
Class:
Hydrozoa
Subclass:
Leptothecatae
Order:
Conica
Family:
Thyroscyphiidae
Genus:
Thyroscyphus
Species:
marginatus

General Description

Colony of individual polyps (hydranths) joined by root-like network of tubular stolons at the base. Colony shape is single stems. Colour: yellowish pink. Up to 1 cm long.

Biology

Colonies of this small species are present most of year but often difficult to see.

Habitat

On algae in intertidal and shallow subtidal areas.

Reefs

Coastal shores

Species Group

Hydroids

Depth

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

Water Column

On or near sea floor

Max Size

1 cm

Diet

Plankton or Particles

Harmful

Generally not harmful but still able to sting bare skin.

Commercial Species

No

Identify

Conservation Status

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

Author

article author Watson, J.

Jan Watson is a consultant with expertise in hydroid taxonomy.

citation

Cite this page as:
Watson, J., 2011, Hydroid, Thyroscyphus marginatus, in Taxonomic Toolkit for marine life of Port Phillip Bay, Museum Victoria, accessed 25 Feb 2025, http://136.154.202.208:8098/species/7108

Text: creative commons cc by licence