Florideae


Florideophyceae, demoted to subclass Florideae in some classification systems, is a class of red algae, estimated to make up about 95% of all known red algae species. It is sometimes merged with the Bangiophyceae into the Rhodophyceae, leaving the subclass Florideae in use.
They were once thought to be the only algae to bear pit connections, but these have since been found in the filamentous stage of the Bangiaceae.
"Florideophyceae" is still used by some authorities.
Once thought only to exhibit apical growth, some genera grow by intercalary growth.
Most, but not all, genera have three phases to the life cycle.

Classification

There are various classification schemes; see red algae. One option is to use the following:

Subclass [Hildenbrandiophycidae]

The subclass Corallinophycidae was introduced in 2007.

Subclass [Ahnfeltiophycidae]

According to molecular clock analysis, Florideophyceae diverged from other red algae about 943 million years ago. It split into Hildenbrandiophycidae ca. 781 mya, Nemaliophycidae ca. 661 mya and Corallinophycidae ca. 579 mya, and ca. 508 mya the split between Ahnfeltiophycidae and Rhodymeniophycidae occurred.