The species recalls T. aestuans (Fr.) Gillet of Europe and North America because of the underlying yellow colors with some black fibrils. Also, it has a mild odor, an acrid taste and a positive macrochemical reaction (bright pinkish violet) with PDAB. However, T. palustre has broader spores, lacks pleurocystidia, and T. aestuans is a conifer associated fungus. Known from collections in the Talamancas where it appears to be associated with Comarostaphylis arbutoides (a member of the Ericaceae) at elevations above 3000 m.

In Costa Rica, T. portentosum can be similarly colored but lacks the PDAB reaction, has a farinaceous odor and taste, and has a white stipe.