#dictyonema

Dictyonema glabratum - A lichen species that is actually hundreds of species

Also known as Cora pavonia, Dictyonema glabratum (Hygrophoraceae) is a tropical, cyanobacterial basidiolichen; it, means that is formed by the symbiosis between cyanobacteria and basidiomycete fungi (unlike most lichen which are formed by the symbiosis of a green algae and an ascomycete fungi).

Thallus of this lichen is large, up to 50 cm or more in diameter, with lobes of 2–10 cm wide, and the upper surface distinctly zonate, pale bluish to greenish gray. Dictyonema glabratum is distributed in the United States (Florida, Hawaii), southern to north-central Mexico, Central America, the Caribbean, South America, and Africa (Mauritius Island, E of Madagascar).

Dictyonema glabratum is an important component of threatened paramo ecosystems, where it acts as a biological fertilizer due to its ability to fix atmospheric nitrogen. But most surprising of this lichen is that a research recently published (21014) has demonstrated that D. glabratum, which was long believed to represent a single species, is actually at least 126 phylogenetically and morphologically distinct species, with statistical analysis predicting more than 400.

References: [1] - [2] - [3]

Liquen / Lichen | ©Jorge Restrepo

Unidentified species of lichen. Cocorna, Antioquia, Colombia.

Does anyone know the species?

Thanks to paisleytaxonomy, who has suggested an identification of this lichen as Dictyonema glabratum. Reviewing the literature it certainly seems that species (although the genus contains about 22 species).

The interesting thing is that Dictyonema is a symbiosis between a basidiomycete fungi and a scytonematoid cyanobacteria, making it both a basidiolichen and a cyanolichen, which is a very rare combination [1].