PORT PHILLIP BAY


Brittle Star 

Ophiactis resiliens Lyman, 1879

View scientific description and taxonomy

Scientific Details

See below for information.

Taxonomy

Phylum:
Echinodermata
Class:
Ophiuroidea
Order:
Ophiurida
Family:
Ophiactidae
Genus:
Ophiactis
Species:
resiliens

General Description

Medium-sized species, disc covered in scales with some small spines along the margin and ventrally. Arms up to six times disc diameter with 3-4 short arm spines on the side of each segment. One oval tentacle scale. Single tricuspid tooth at the apex of each jaw and two small oval papillae on each side. Disc olive green or dark grey, radial shields a contrasting white, arms often with blotches on green pigment spaced on either side of the dorsal midline. Older animals with faded pigmentation.

Biology

This species reproduces by releasing eggs or sperm in May-June. The resulting larvae are called ophiopleuti, have long calcite spines, can feed on phytoplankton and swim for three months before settlement. Ophiactis resiliens is a suspension feeder; individuals bury their discs in coarse sediments, under rocks, or in rock crevices, with 1-4 arms extending vertically into the current. The arms alter their orientation according to the current flow, and the tube feet are widely spread laterally. Particles of food are caught on the papillate tube feet, less commonly on the arm spines, and are transferred to the mouth in a "collapsing wave" of tube feet. Near the arm base the food is compressed into a bolus that is passed to the mouth. Ingested food consists mainly of diatoms.

Habitat

Reefs, brown algae, sponge and bryozoan beds, under rocks and on holdfasts of kelp.

Reefs

Sponge gardens

Distribution guide

New Zealand and Tasman Sea, including southern and eastern Australia.

Species Group

Seastars and allies Brittle stars

Depth

Shallow (1-30 m)

Water Column

On or near sea floor

Max Size

Diet

Plankton or Particles

Commercial Species

No

Global Dispersal

Recorded in Australia

Species Code

MoV 2538

Identify

Conservation Status

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

Author

article author O'Hara, T.

Dr. Tim O'Hara is a Senior Curator of marine invertebrates at Museum Victoria.

citation

Cite this page as:
O'Hara, T., 2011, Brittle Star, Ophiactis resiliens, in Taxonomic Toolkit for marine life of Port Phillip Bay, Museum Victoria, accessed 19 Oct 2017, http://portphillipmarinelife.net.au:8098/species/6606

Text: creative commons cc by licence