• Proposed
  • Under Assessment
  • Preliminary Assessed
  • Assessed
  • VUPublished

Tripospora venezuelensis E. Müll.

Search for another species...

Scientific name
Tripospora venezuelensis
Author
E. Müll.
Common names
 
IUCN Specialist Group
Cup-fungi, Truffles and Allies
Kingdom
Fungi
Phylum
Ascomycota
Class
Eurotiomycetes
Order
Coryneliales
Family
Coryneliaceae
Assessment status
Published
Assessment date
2017-01-27
IUCN Red List Category
VU
IUCN Red List Criteria
D2
Assessors
Minter, D.
Reviewers
Mardones, M., Minter, D. & Vasco-Palacios, A.M.

Assessment Notes

The content on this page is fetched from The IUCN Red List of Threatened Species: https://www.iucnredlist.org/species/74847931/109976379

Justification

This fungus is an obligate symbiont of the conifer Retrophyllum rospigliosii (Podocarpaceae) (itself assessed as Vulnerable on The IUCN Red List; Gardner and Thomas 2013). It is known from only one location in Venezuela, and has been observed only once, in 1963 (Müller and Dennis 1965). If the conifers where the fungus occurs were to be logged (this is the main threat to the conifer) then the fungus could become Critically Endangered or Extinct in a very short time. Therefore, it is listed as Vulnerable under criterion D2.

Geographic range

The distribution of this species was assessed using, as a minimum, the information sources recommended by Minter (2014). This fungus is known from only a single collection made in La Carbonera, Mérida, Venezuela, in March 1963. The altitude of its only known station is 2,200 m above sea level in cloud forest. The altitude range of the only plant with which it is known to occur is 1,500-3,750 m above sea level. In the absence of any other information, and for the purposes of the current assessment, this fungus is assumed to occur only at the known site.

Population and Trends

There is no information available on population size or trend but it is assumed to be declining given the loss of the host tree.

Population Trend: decreasing


Habitat and Ecology

Like other members of the genus Tripospora, and most other members of the family Coryneliaceae to which it belongs, Tripospora venezuelensis appears to be a specialized and obligate parasite inhabiting only a single plant genus and perhaps only a single species within that genus. It is known only from dead portions of current year's growth living twigs and leaves of the conifer Retrophyllum rospigliosii (Pilg.) C.N.Page (synonym Podocarpus rospigliosii). The life-cycle and biology have not been investigated, but co-evolution of this fungus and its associated plant seems likely as colonisation by the fungus and subsequent production of carpophores cause minimum damage to host tissues: discoloration of colonised leaves, for example, is very localised, and there is no evidence of premature leaf fall. There are no reports of the fungus causing economic damage to the plant. The possibility that the fungus may have some beneficial effect on the tree has not been considered. An asexual state is produced before the sexual state appears. The function of the conidia (asexual state spores) is not clear. Dispersal, by ascospores (the sexual state spores), possibly involving wind during humid weather, occurs when the fertile extension of the fungus carpophore expands and opens, revealing its upper chamber where dry masses of ascospores have accumulated. The ascospores bear a strong resemblance to the tetraradiate conidia of aquatic hyphomycetes, but the possibility that they too are adapted to specialized water dispersal has not been investigated (Johnson and Minter 1989, Minter 2006).

Threats

Tripospora venezuelensis is known only from dead portions of living twigs and leaves of Retrophyllum rospigliosii, and appears to be obligately associated with that tree, unable to grow on any other substratum. Retrophyllum rospigliosii is currently assessed globally as Vulnerable A2acd. According to Gardner and Thomas (2013), the main threat to the tree across its range is logging for its valuable timber, although land conversion for agriculture is an additional threat. In Peru it was quite common in the cloud montane forests of Departments of Junín and Pasco (“Selva Central”) (Gardner and Thomas 2013). During the 1960's-1980's, however, logging activities increased as a result of the widespread availability of chainsaws and more developed road systems (Gardner and Thomas 2013), and this dramatically reduced the natural stands. Logging methods employed included the removal of large areas of trees on steep mountain sides by the use of reinforced cables (Gardner and Thomas 2013). Today it is very rare to see significant stands of this conifer in Peru, and it now occurs as scattered trees throughout areas where it was once dominant (Gardner and Thomas 2013). In Colombia it has a national listing of Near Threatened even though it has been exploited for its timber and there are still relatively large stands in some locations (Cárdenas and Salinas 2017). In Bolivia, where the tree has a very restricted distribution, it is under threat from agroforestry. It is unclear what the situation is in Ecuador and Venezuela but because of its valuable timber it is assumed that natural stands have been somewhat reduced (Gardner and Thomas 2013). 

Tripospora venezuelensis itself faces the same threats as its associated tree. The only known location for this fungus is close to, but outside, the national park Sierra de la Culata, in an area where satellite images (Google Maps, accessed 27 January 2017) suggest there has been significant deforestation. Given its montane habitat, climate change may be an additional threat. It may also face further threats, as yet not identified. In the absence of any other information, and for the purposes of the current assessment, this fungus is assumed to occur only at the known site.

Conservation Actions

Further research is required to determine the range of this fungus and to find out more about its life history and ecology.

Source and Citation

Minter, D. 2020. Tripospora venezuelensis. The IUCN Red List of Threatened Species 2020: e.T74847931A109976379. https://dx.doi.org/10.2305/IUCN.UK.2020-3.RLTS.T74847931A109976379.en .Downloaded on 31 January 2021

Country occurrence