Godiva graces one stamp.

Godiva graces one stamp. Photo: Courtesy Australia Post

Some of Australia's little-known and rarely noticed underwater wonders will grace envelopes from this week when a new series of stamps is launched tomorrow.

The photographs by Perth marine biologist Clay Bryce feature in a new stamp series from Australia Post.

Six images of colourful mollusc-like marine creatures, known as nudibranchs, (pronounced noo-de-branks), shot around the Australian coastline, are being issued on Tuesday in the Underwater World series, in denominations of 60 cents, $1.20 and $1.80.

A slug-like creature captured on film.

A slug-like creature captured on film. Photo: Courtesy Australia Post

Mr Bryce, who works with the Western Australian Museum, has studied marine life for 37 years and said he had a particular interest in searching for and photographing nudibranchs. "They have really interesting shapes, or what we call body plants, and they are very brightly coloured," he said.

Some of his photography has appeared before on Christmas Island and Cocos Keeling Islands stamp issues. Australia Post approached him to see if he had any nudibranch images that might suit the latest underwater series.

He said he particularly liked the unusual colouring of Chromodoris westraliensis, a black-and-purple nudibranch, endemic to WA waters, which featured on one of the 60 cent stamps.

Thorunna Florens.

Thorunna Florens. Photo: Courtesy Australia Post

When diving for marine photographs, he shoots with Nikon cameras fitted with Nikkor lenses inside waterproof camera housings from the Austrian manufacturer Subal. He said he routinely carried three different cameras fitted with lenses to shoot at different focal lengths. He said many photographs used in the series were shot on film rather than digital cameras.

Australia Post has depicted the nudibranchs bobbing independently just under the surface of clear water, whereas nudibranchs are not free swimmers. The original photographs were shot with the nudibranchs clinging to their habitat, with other marine life in the background.

To find nudibranchs to photograph, Mr Bryce said it was important to look for food sources such as corals or sponges. He said nudibranchs lived at all depths.

twitter Follow The Age on Twitter @The Age