[4] While this synonymisation has been debated, recent molecular phylogenetics studies support a broader circumscription of Megalaria that includes Catillochroma, pending further research with expanded taxon sampling.

Instead, the edge of the apothecium is made up of the true exciple, which is a layer of hyphae (fungal filaments) arranged in a vertical or anticlinal manner.

The hymenium (the spore-producing tissue) of the apothecia is generally colourless to pale brown, while the upper layer, called the epithecium, contains pigments that turn from greenish to dark purple when treated with potassium hydroxide solution (K+).

These asci are of the Lecanora-, Bacidia-, or Biatora-type, which means they feature a broad, non-reactive (non-amyloid) apical cushion and a distinct ocular chamber.

[6] The spores produced by Megalaria are generally ellipsoidal in shape, divided by one internal septum (1-septate), colourless, and smooth with thick walls.