Blue Green Chiton

Chiton glaucus are oval in shape, with a slightly elevated yet definite ridge running down the back of the organism. This results in a bilateral symmetry. The size of the organism is commonly 30–35 mm long.

Taxonomists primarily use characteristics of the valves and the girdle to tell the difference between species, and this is the case for Chiton glaucus. The shell consists of eight overlapping valves. It is fairly large, up to 55 mm in length, with 6 intermediate valves between 2 terminal valves at either end of the organism. These valves are surrounded by a girdle, which helps with adhesion to surfaces and in the case of Chiton glaucus it is covered in large scales.

Within New Zealand, Chiton glaucus is found on the North, South and Stewart Islands, as well as the Chatham Islands. It is also present in Tasmania, becoming very common in estuaries. It is thought to have been introduced to the area through shipping activity between Australia and New Zealand.

Chiton glaucus show clear daily patterns of activity; they remain hidden during the day to escape visual predators and then during the night they travel to the tops of the rock to feed on the algae that has grown there since the previous night.

According to research done by Robert Creese who analysed the contents in the gut of C. glaucus it was found that the main component of its diet is that of coralline algae. Other research suggests a broader range of organisms within its diet including encrusting organisms (sponges, bryozoans etc.) and on diatoms and algae in a grazing type method.

Little is known about the habits of chiton in general, but observations have been made to further understand the processes relating to spawning amongst other processes. Research conducted in Queensland on the Great Barrier Reef saw that a common chiton of this area seemed to consistently choose to spawn on the night of a full moon. This also seemed to correlate with conditions at the time as if they were not favourable, for example a rough tide, spawning would not occur and was delayed until the next full moon. This was the case even if in between full moons there was a time period where the weather and tide were favourable. Generally, the spawning of chitons are usually synchronous but not necessarily correlated with any particular stage of the lunar or solar cycle.