Phasianotrochus irisodontes, common name maireener, rainbow kelp shell, or green necklace shell, is a species of sea snail, a marine gastropod mollusk in the family Trochidae, the top snails.

[2][3] Found off the coast of Tasmania, the shells have been used to make necklaces by Aboriginal Tasmanian women in a cultural practice going back thousands of years.

The effects of climate change and human recreational activities have reduced the populations of the snails in recent years.

It is polished, yellowish, pink, or olive-green, with reddish or olive longitudinal lines in pairs, sometimes separate on the body whorl, and usually with numerous narrow, rather obscure spiral pink or yellowish lines.

[citation needed] Numbers have been observed to have been decreasing in recent years, with the causes put down to recreational activities reducing the amount of kelp habitat, predatory fish attracted by excess feed escaping from abalone farms, and storms eroding the seabed.