Basidiocarp resupinate, effuse, thin, lilaceous pink when fresh, yellow-ochre when dried. Microscopically is distinguished by its big (17-25 x 7-9 µm), cylindrical to suballantoid spores.

Tulasnella robusta is a very rare tulasnelloid fungi recorded only once in Tierra del Fuego (Argentina). This single record was in 1975 and no further records have been reported, eventhough the extensive surveys conducted between from 1995 to 1999 in the island. This seems to indicate a decline in the population of the species. On this base the species should be assessed as near threatened (NT) or vulnerable (VU) under the criteria A4 (a), D.

Recorded in only one locality in Tierra de Fuego island: Ushuaia, El Martial glacier valley.

Population size unknown. The species is known from one location.
Population Trend: Presumably decreasing

Growing on rotten wood of Nothofagus betuloides.

Presumably very small population.

The species is poorly known since it has been recorded only once. It is important to survey intensively the locality where it was found in order to confirm it presence and assess population size.
Molecular phylogenetic studies are also needed.