Compsopogon

Compsopogon caeruleus, known as staghorn algae, is a species of red algae that lives in fresh water. It is a common nuisance in freshwater aquaria.^[1] It is the only species in the genus Compsopogon and the only representative of the family Compsopogonaceae. It is found in North America, South America, Europe, Africa,^[2] Asia, Australasia and Oceania. Compsopogon can tolerate a wide range of conditions in freshwater streams and occasionally in brackish lagoons and estuaries.^[3] It propagates by asexual spores.

Compsopogon
Compsopogon sp.
Scientific classification
(unranked):	Archaeplastida
Division:	Rhodophyta
Class:	Compsopogonophyceae
Order:	Compsopogonales
Family:	Compsopogonaceae
Genus:	Compsopogon
Species:	C. caeruleus
Binomial name
Compsopogon caeruleus (Balbis ex C.Agardh) Montagne

Compsopogon presents a thallus of simple cylindrical cells inside large covered cortical cells. In more mature and large thallus interior cells can be disintegrated, leaving only the outer cortex.

The species exhibits a wide phenotypic plasticity in studies such as field observations, with the result that historically many species have been described, when current thought treats it as a single species. There are two main morphologies in Compsopogon, one displaying regular cortical cells (morphology caeruleus), the other having cells with extra rhizoidals (morphology leptoclados).^[4]