This centric diatom is called Coscinodiscus and lives in marine habitats. In fact, most centric diatoms live in marine waters, that’s probably one of the reason I haven’t encountered one before now! Diatoms are present in almost every salted water environments and are responsible for at least 25% of the oxygen produced on earth! That is totally crazy since we can’t even see them with the naked eye there also many many diatoms living in freshwaters like ponds and lakes.