Chromalveolate

Chromalveolata is a eukaryote supergroup first proposed by Thomas Cavalier-Smith as a refinement of his kingdom Chromista, which was first proposed in 1981.

Chromalveolates
Clockwise from top-left: a haptophyte, some diatoms, an oomycete, a cryptomonad, and Macrocystis, a phaeophyte
Scientific classification
Domain:	Eukaryota
(unranked):	Bikonta
Kingdom:	Chromalveolate Cavalier-Smith 1998
Phyla
Heterokontophyta Haptophyta Cryptophyta Alveolata (superphylum) Ciliophora Apicomplexa Dinoflagellata

The origin of the Chromalveolata was thought to be a secondary endosymbiosis between a bikont (cell with two flagella) and a red alga.^[1] This union led to plastids containing chlorophyll c. In Cavalier-Smith's classification, the Chromalveolata was one of the six major groups within the eukaryotes.^[2]

The classification has been challenged.^[3][4]