This species has been described from decaying wood of Araucaria araucana. It is the only known host, and so would be limited by its very small, and severely fragmented range (<500 km2). Therefore, this species is listed as Endangered, but we recommend further research to confirm host specificity.
The species is characterized by it resupinate, pellicular basidiome, smooth, whitish hymenial surface and rhizomorphic margin with distinct white hyphal strands. Microscopically it is characterized by tubular, thin-walled cystidia with obtuse apex, some widened at the base.
Athelopsis tenuicystidiata is a very rare corticioid fungi recorded in only one locality of Patagonia Argentina growing on decayed wood of the endangered tree species Araucaria araucana. The ongoing decline of its host tree, the fragmentation of it habitat, and it rareness, point out the vulnerability of this species.
VU A4 c this criterion applies because the decline of its host is expected to drive a reduction >30% in the population size in a period of 3 generations (100 years)
EN B1 B2 a b(i, ii, iii) this criteria applies because area of occupancy (estimated on the base of AOO of its host), is less than 500 km2
NT C1 Even though the host is declining, the area were the species was found is a protected area. Therefore, as threats are less severe, a reduction not greater than 10% in the number of mature individuals in the next 100 years is expected.
NT D1 D2. Even though the species is known from only one locality, a conservative estimation of a number of individuals < 2000 and or ≤10 localities is inferred, assuming the species is present in some unexplored areas.
It is known only from one locality in Argentina, (Neuquén, Villa Pehuenia; Pérez Gorjón et al. 2012). The range of the known host is 392.51 km2 (Premoli et al. 2013). The occupied area of this species is estimated as lower since it has been recorded only in the most humid area of the host range. Even though the species has been recorded in only one locality, the potential area of occupancy (AOO) per IUCN guidelines is assessed as <500 km2, and severely fragmented.
The population is assumed to be declining, as although the species is known from only one locality, there has been a decline in its host’s range and a decline in the habitat quality (Premoli et al. 2013).
Population Trend: Decreasing
This species has been found fruiting sparsely on decayed wood of Araucaria araucana in mixed forests of A. araucana and Nothofagus spp.
The main threat to this species is the decline of it host and habitat. Its host, Araucaria araucana, is classified as Endangered due to the decline of its population, the decrease of its AOO, the severe fragmentation and declining habitat quality. The threats impacting A. araucana in particular are from agriculture, cattle farming, logging and increases in fire frequency. All these problems negatively affect this fungal species since A. araucana is its only known host.
Protection of the species’ host and habitat is needed as well as habitat restoration.
Research into the full geographic range needs to be conducted, focusing in particular on all areas occupied by its host, Araucaria araucana. Such studies could also help to estimate the population size and potential rate of decline. Research into host specificity would be useful to confirm whether it only grows on A. araucana.
There is no use/trade of this species.