Initially described as part of the genus Grimmia, it was reclassified into Coscinodon by Polish bryologist Ryszard Ochyra in 2004, owing to similarities with several South American species.

C. lawianus is likely a remnant of the Neogene flora of Antarctica which survived the rampant glaciation and cooling of the continent on remote rocky outcrops.

Ochyra cited the moss's similarities to South American coscinodons C. pseudocribrosus and C. bolivianus as supporting the reclassification.

[5] All populations of C. lawianus are sterile, reproducing solely through asexual reproduction, spreading through filamentous gemmae.

These are characteristically biplicate and generally pointed, with a sharp central fold along the middle on the distal portion; their undersides are smooth and concave.

[10] The southernmost known colonies have been found at the Tottan Hills of Queen Maud Land, at a latitude of 75 degrees south.

This ecosystem was destroyed by rampant cooling and glaciation on the continent during the Neogene, leaving the moss isolated on the rocky outcrops and nunataks.

It prefers high-altitude soils with low levels of nutrients, avoiding areas directly adjacent to the coast with significant sea bird presence.

[13] The microscopic filamentous fungi Cladosporium, Epicoccum nigrum, Phoma herbarum, and Thelebolus microsporus have been observed growing within samples of C.