Nudibranchs are marine molluscs renowned for their flamboyant colour patterns. They have evolved to the point where they no longer need the passive defence of a shell, instead opting for special chemical secreting glands or recycled stinging cells to keep their soft bodies intact.
Nudibranchs have bright, colourful bodies that not only advertise their toxicity and distastefulness to would-be predators, but also provide near perfect camoufl age to hide their delicate bodies. They also have an amazing array of body parts, including a rasp-like “tongue”, called a radula used to scrape their food, finger-like cerata protruding from the back and sides, which are extensions of the gut and some even have extended mantles for swimming.
They have a set of exposed frilly gills and, most strange indeed, two “nose-stalks” termed rhinophores. The rhinophores are perched on top of the animal’s head allowing it to smell the water for food and possible mates.
Nudibranchs can be found in all habitats from the deepest ocean to the shorelines of every continent. They come in many sizes, are beautiful to behold and have developed survival strategies, which defy the imagination.
Title: Underwater World – Australia
Date of Issue: 8 May 2012
Denominations: 3 x 60c, 2 x $1.20, 1 x $1.80