A sand-dwelling anemone with a disc to about 40 cm (16 in), its tentacles in two sizes - longer simple ones and shorter branched ones - and the whole column buried so that the crown sits flush with the bottom. Colour is muted, brown through grey-green with paler tips, which makes it easy to swim past on open sand.
It catches passing animals with stinging cells and supplements the diet through symbiotic algae, which is why it occupies sunlit sand rather than shade. The species was named for Wilhelm Hemprich, who died at 29 collecting in this region on the Prussian expedition of the 1820s - a survey that named a long list of animals here and cost both its naturalists their lives. Recently moved out of the genus Thalassianthus, so older field guides list it under a different name.
- tentacles of two lengths, the short ones branched at the tip
- brown to grey-green with paler tentacle tips
- column buried, only the disc at sand level
- disc up to 40 cm across
