Monotypic algae orders

REDIRECT Oedogoniaceae

REDIRECT Trentepohliaceae

REDIRECT Coleochaetaceae

REDIRECT Stylonemataceae

Hildenbrandiales is an order of crustose forms red alga which bear conceptacles and produce secondary pit-connections. They reproduce by vegetative gemmae as well as tetrasporangia, which are produced inside the conceptacles. The way in which the tetraspores are produced is unusual enough to justify the formation of this distinct order. Some members of the order are known from freshwater rivers as well.

Chaetosphaeridiales is an order of green algae.

Pseudoscourfieldiales is an order of green algae in the class Pseudoscourfieldiophyceae.

REDIRECT Thoreaceae

REDIRECT Glaucophyte

REDIRECT Microthamniaceae

REDIRECT Mesostigma

REDIRECT Oltmannsiellopsidaceae

REDIRECT Compsopogonophyceae