There are species of nudibranch that are very bright and colourful. This is often a sign in nature that conveys the message: "don't mess with me!". Brightly coloured animals in the sea can be toxic to other sea life or at the least distasteful.
In the case of Hallaxa translucens it is rarely seen. The reason for this is that it hides under rocks and also matches its sponge food source perfectly. The stout body is translucent with an opaque cream netting that resembles the pores of the sponge. In the photo above you can compare the sponge food source with the nudibranch's body. Nice match!
This species has bulbous gills that resemble a "goblet" in shape. There is a raised area of mantle being depressed in the centre that almost surrounds the gills.
When at rest the animal takes on a roundish shape. The only things that differentiates it from the background surface are the two little dark rhinophores retracted into their pockets.
Details: Photo and text by Gary Cobb, Nudi Ledge, Currimundi Reef, Sunshine Coast, Queensland, Australia
When we decided to put up on our website a taxonomic list of the opisthobranchs we have found in the Sunshine Coast region we wanted to include helpful descriptions of the orders and families. We found that this information is not readily available anywhere. We therefore set about the laborious task of collating it from many many sources (including our own observations) bringing it together and writing from scratch a coherent paragraph for each family and order based upon external features and behaviour that would be easily discernible by the fieldworker and/or from photographs.
We believe all this information should be freely available and easily accessible by all those interested in these amazing creatures. It is available on our Species List/Family Descriptions page for all to access, read and make use of.
To find that several of these have been lifted off our page verbatim and used in a scientific report without acknowledgement is most disappointing and an unconscionable act.The authors should be ashamed. If they had bothered to contact us we would have willingly given of our time and resources to assist them to get their information up to date and coherent. Read Glaucidae for a family description they attempted to write themselves.
Here is a comparison of just three out of the many for you to make your own judgement. Click thumbnail for larger image.
Our Latest Find
Tylodina corticalis (Tate, 1889)
35 mm, gills peaking out from under the shell,
Nudi Retreat, Caloundra, Sunshine Coast, QLD, Australia
Our Nudibranch website
We embarked upon this adventure of ours while diving here on the Sunshine Coast, Queensland, Australia. Upon realizing the amazing variety of nudibranchs we were seeing, we developed an appetite for not only finding as many different species as possible but identifying and learning all we could about these most amazing creatures of the sea. nudibranch.com.au was born when a friend of Gary’s suggested we share our knowledge with the world. The site commenced in March 2003 when we set out on our quest to find, identify and record all of the nudibranchs here in our area. The ever changing sea and seasons give up new surprises every visit whether they are subtidal or intertidal.
We describe our searching and identifying component of the quest as The Treasure Hunt, and the recording thereof upon the web site as The Never Ending Story.
We welcome for inclusion on the site the findings of other workers in this area that we may not have yet recorded.
From this website a Nudibranch Identification book called Undersea Jewels - A Colour Guide to Nudibranchs was published in 2006. The book is a 'Colour Guide'. After all that is the first thing anyone remembers about first seeing a Nudibranch.
LOCATE, RECORD, IDENTIFY and POST every species of OPISTHOBRANCH to be found on the Sunshine Coast Queensland, Australia. Learn more>
To LOCATE through scuba diving and intertidal searching.
To RECORD by underwater and studio/taxonomic photography (including microscopy photography) of the specimens.
To IDENTIFY these speciesthrough invaluable support fromqualified authorities in this field and developing reference resources.
To POST upon our web site not only images of the species and their natural history behaviour but also information concerning size abundance and localities. Additionally to disseminate to other sites information considered unusual (see Useful Resources).
Towards achieving these aims we will continue to acquire and develop the necessary equipment, resources and knowledge.
Have fun, learn and enjoy the Earth's greatest creatures!