M. lyrata M. majuscula M. malaccitula M. megalateralis Macroconstrictolumina is a genus of lichen-forming fungi in the family Trypetheliaceae.

[3] The excipulum, which is the outer tissue layer of the ascomata, is made up of tightly interwoven cells, appearing brownish to colourless beneath the surface.

The hamathecium, which is the tissue filling the cavity of the ascomata, consists of very thin, hyaline (transparent), branched, and interconnecting filaments called pseudoparaphyses, all set in a gel-like substance.

[3] The asci, or spore-bearing cells, are club-shaped, short-stalked, and open via a fissitunicate mechanism, meaning they have a double wall that splits to release spores.

[3] Macroconstrictolumina consists of lichen-forming fungi that predominantly inhabit terrestrial, lowland to lower montane tropical regions, often growing on bark.