Nudibranchs of NENSW

ORDER NUDIBRANCHIA (Nudibranchs)

Species: Flabellina rubrolineata (Family FLABELLINIDAE)

Location: "Cod Hole" Julian Rocks Marine Reserve, Byron Bay, New South Wales
Depth: 14-16 metres
Date: 12/6/03
Photo by: Simon L Hartley

Solar powered slugs...

Some Aeolidae and Glaucidae nudibranchs are able to retain and cultivate symbiotic plant cells (zooxanthellea) from corals, hydoids and anemones on which they feed. Long, finger like projections on the backs of these nudibranchs (called cerata) house these plant cells and provide a large surface area for photosynthesis. A nudibranch like Pteraeolida ianthina (above) can live entirely on the energy produced by these plants, effectively running on solar energy.

Other nudibranchs retain the pigments of plant cells on which they feed, within their bodies. Providing very efficient camouflage against predation. Still other retain the stinging cells of cnidarians to use in thir own defence.

Species: Pteraeolida ianthina (Family GLAUCIDAE)

Location: "Hugho's Trench" Julian Rocks Marine Reserve, Byron Bay, New South Wales
Depth: 9-10 metres
Date: 29/11/97
Photo by: Simon L Hartley

Species: Phidiana sp.

Location: "Hugho's Trench" Julian Rocks Marine Reserve, Byron Bay, New South Wales
Depth: 9-10 metres
Date: 29/11/97
Photo by: Simon L Hartley

Species: Marianina rosea

Location: Julian Rocks Marine Reserve, Byron Bay, New South Wales
Depth: ? metres
Date: ?
Photo by: Danny Bucher

Species: Favorinus tsuruganus

Location: "Codhole" Julian Rocks Marine Reserve, Byron Bay, New South Wales
Depth: 18-22 metres
Date: ?
Photo by: Danny Bucher

Glaucilla marginata (pictured to the left) is an interesting nudibranch often found by beach combers following periods of intense onshore winds. These bright blue coloured creatures actively hunt hydroids (like by-the-wind-sailor, Velella velella, and Porpita porpita) and siphonophes (bluebottle or Portuguese man o' war, Physalia physalis) near the surface of the ocean (in the pleuston). They are able to ingest the stinging cells of their prey and use these cells for their own defence. This specimen was collected at Evans Head on the NSW north coast in 2000.

Another nudibranch that has a similar life style is Fiona pinnata. This nudibranch usually feeds on goose barnacles (Lepas pectinata or Lepas australis) but is also known to feed on by-the-wind-sailors and bluebottles. Unlike Glaucilla however, Fiona pinnata is unable to swim and instead must inhabit floating objects (like drift wood) or host prey. The following images were taken under a stereo microscope in the biology laboratory at Southern Cross University. This specimen was collected off Byron Bay on the NSW north coast (All photo's by: Danny Bucher).