[1] It is a freshwater genus; they are often found in soft, boggy or acidic waters.

[2] Radiofilum consists of unbranched filaments of cells, surrounded by a very thin mucilage layer.

[2] The genus Radiofilum as currently circumscribed appears to be a polyphyletic grouping of species.

Some work has been done to transfer species to other genera,[3] including Interfilum[3] and Flintia.

[4] The type species, Radiofilum conjunctivum, belongs to the class Trebouxiophyceae and is phylogenetically close to the genus Microthamnion.