[1] It was unambiguously identified in Acaryochloris marina in the 1990s.
[2] It is present in cyanobacteria which use energy captured from sunlight for photosynthesis.
[3] Chl d absorbs far-red light, at 710 nm wavelength, just outside the optical range.
[4] An organism that contains Chl d is adapted to an environment such as moderately deep water, where it can use far red light for photosynthesis,[5] although there is not a lot of visible light.
[6] Chl d is produced from chlorophyllide d by chlorophyll synthase.