Cyanidiophyceae
Cyanidiophyceae is a class of unicellular red algae within subdivision Cyanidiophytina, and contain a single plastid, one to three mitochondria, a nucleus, a vacuole, and floridean starch.They originated in extreme environments with high temperatures and low pH, which allowed them to occupy ecological niches without any competition.[3] While still found in extreme environments, they have also adapted to live along streams, in fissures in rock walls and in soil, but usually prefer relatively high temperatures.Except for Galdieria partita, which can reproduce sexually,[5] reproduction is asexual by binary fission or formation of endospores.[6] The group, consisting of a single order (Cyanidiales), split off from the other red algae more than a billion years ago.