The type specimen was collected by the author from Grande Anel Rodoviário [pt] (São Paulo) at an elevation of 670 m (2,200 ft).

The apothecial disc is initially flat but becomes slightly convex, ranging in colour from beige to dark brown.

[1] The excipulum of Malmidea rhodopisoides is of the piperis-type, hyaline (translucent) at the periphery, with the inner part containing hydrophobic granules of norsolorinic acid.

These spores are broadly ellipsoid to fusiform, lack septa (internal partitions), with a uniformly thickened wall and a halo approximately 1 μm thick.

In contrast to M. isidiifera, which lacks norsolorinic acid in the inner layer of its structural excipulum and features a thallus covered with elongated, non-granular outgrowths (isidia), Malmidea rhodopisoides has traits that are intermediate between these two species.