PORT PHILLIP BAY


Hydroid 

Monotheca flexuosa (Bale, 1894)

View scientific description and taxonomy

Scientific Details

Family level detail.
Hydroids branched or unbranched, pinnate, usually with alternate hydrocladia, hydrotheca cup-shaped, one nematotheca in front of hydrotheca and one on each side behind hydrotheca. Gonophores protected by a gonotheca female gonophore producing eggs. The family Plumulariidae encompasses many genera and species world-wide, from shallow to deep water. Species range from very small fast growing colonies to large colonies that may live for many years.

Genus level detail.
Colonies comprising many simple erect segmented stems, each segment (internode) bearing short, alternate hydrocladia (hydrocladia) each hydrocladium on a stem and bearing a single hydrotheca. Gonotheca barrel-shaped. Species level identification requires microscopy.

Species identification.
Colonies comprising many stems. Hydrotheca cup-shaped, nematothecae on stem internodes, median nematotheca behind hydrotheca wineglass-shaped, one of same shape at each side of hydrotheca (twin laterals). One to several gonothecae borne on the lower stem, large, barrel-shaped with an obliquely truncated summit. Colour: colonies white, gonophores often iridescent white to yellow. Up to 1 cm long.

Taxonomy

Phylum:
Cnidaria
Class:
Hydrozoa
Subclass:
Leptothecatae
Order:
Conica
Family:
Plumulariidae
Genus:
Monotheca
Species:
flexuosa

General Description

Colony of individual polyps (hydranths) joined by root-like network of tubular stolons at the base. Colony shape is feather-like (pinnate). Colour: colonies white, gonophores often iridescent white to yellow. Up to 1 cm long.

Biology

Colonies of this species occur throughout most of year. They are fertile late winter to summer.

Habitat

On algae and other invertebrates, common on jetty piles, in sheltered bays and ocean.

Reefs

Distribution guide

New Zealand and Australia.

Species Group

Hydroids

Depth

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

Global Dispersal

Recorded in Australia

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, Monotheca flexuosa, in Taxonomic Toolkit for marine life of Port Phillip Bay, Museum Victoria, accessed 27 Apr 2017, http://portphillipmarinelife.net.au:8098/species/7117

Text: creative commons cc by licence