It has been applied to microfossils of Devonian age with fungal affinities, though these taxa have since been recognized as an early growth form of Tortotubus.

[2] The form genus Ornatifilum was erected by Burgess and Edwards in 1991 to describe tubular fossils retrieved by acid maceration from the late Silurian.

[1] It was originally intended as a form genus, to facilitate stratigraphy and environmental reconstruction; the fossils do not display enough features to classify them confidently, even at a kingdom level.

[2] The type species of the genus consists of flattened filaments – perhaps an artefact resulting from post-burial pressure.

[4] The filaments are septate, with the septa looking like "pinch points" where the tube is slightly constricted – like a twisted balloon.