This is an edible species endemic to the center of Mexico, currently collected for self-consumption. It is restricted to highly endangered habitat. Data on its distribution are robust and its populations should not double the current registers.
The species should be listed as Vulnerable under the criteria A3c; B2ab(ii,iii,iv) since: due to global warming its population is projected to reduce significantly due to a decline in are of occupancy (AOO) of 41.5% in the next 50 years. It already occupies a restricted area of 1500 km2, even accounting for possible unsampled areas its AOO would be less than 2000 km2, its six known subpopulations are truly fragmented acting as “sky islands” and are genetically isolated, the decline of its area of occupancy is observed and projected due to area reduction, decrease of habitat quality and a reduction of subpopulations.
Flammulina mexicana, grows exclusively on wood of Senecio cinerarioides at high elevation (3000 - 4000 m) on Central Mexico volcanoes. It is characterized by a hymeniform pileipelli and a bilateral gelatinized subhymenia. It is distinguished from F. callistosporioides in the elements of the pileipellis, which are globose in F. callistosporioides and more elongated in F. mexicana. Also F. callistosporioides was described from Argentina.
Flammulina mexicana is an edible mushroom locally valued in the center of Mexico with a high potential for its commercial cultivation. However, it is harvested in nature for local consumption without any conservation strategy. Even while it is a saprobe, its substrate is restricted exclusively to dead small trunks and branches of Senecio cinerarioides whose habitat is very restricted. These species only develop in high mountain (above 3000 m) Pinus hartwegii open forests in secondary succession vegetation. These forests are the most imperiled temperate forest in Mexico due deforestation and climate change. This species should be protected because its biocultural importance, biotechnological potential, its restricted geographic range and the severely endangered status of its habitat.
This species is restricted to the Transmexican Volcanic Belt in the higher mountains of central Mexico from 3000 to 4000 m. It has been recorded 8 times in La Malinche Volcano in Tlaxcala, 8 times in the Iztacihuatl-Popocatepetl volcanoes in Puebla and the State of Mexico, 5 times in the Nevado de Toluca in the State of Mexico, 2 times in la Sierra de las Cruces in the State of Mexico, 1 time in Pico de Orizaba in Veracruz and 1 time in Cofre de Perote in Veracruz (Redhead et al 2000, Arana et al 2014 GBIF 2018).
Mexico: State of Mexico, Puebla, Tlaxcala, Veracruz
Flammulina mexicana is endemic to central Mexico. There, it has been recorded 25 times in 13 localities all of them at high elevations (3000-4000 m) in the Transmexican Volcanic Belt. These localities belong to six subpopulations: Nevado de Toluca volcano, Sierra de la Cruces mountain range, Sierra Nevada mountain range (Popocatepetl-Iztacihuatl), La Malinche volcano, Pico de Orizaba volcano and Cofre de Perote volcano.
The close phylogenetic relationship between F. populicola from California and F. mexicana, and the observation that F. mexicana is nested within the F. populicola clade suggests that F. populicola was the most recent common ancestor of F. mexicana. However, F. mexicana is reproductively isolated from all F. populicola collections tested and is morphologically distinct (Hughes et al 1999, Petersen et al 1999).
Flammulina mexicana is a high-altitude species, found growing exclusively in Senecio cinerarioides at altitudes of 3000-4000 m. Heat intolerance or cultivation of land surrounding mountain tops restrict F. mexicana to small isolated “sky island” populations, subject to genetic drift (Hughes 1999).
Population Trend: Stable
Flammulina mexicana is restricted to high altitudes (3000-4000 m) in neotropical Alpine forests in the center of Mexico. There it produces fasciculose fruit bodies in groups of 5-30, lignicolous, growing exclusively woody debris or on dead branches of living Senecio cinerarioides.
Climate change is the mayor threat for F. mexicana populations. Since global warming is affecting dramatically alpine ecosistems, P. harwegii is going to reduce its potential habitat in 41.5% in the next 50 years. Particularly, the P. hartwegii subpopulations in the Transmexican Volcanic Belt, where F. mexicana develops, are in high risk of extinction (Arriaga y Gómez 2004). Additionaly fires reduce the secondary vegetation shrubs in this ecosystem damaging the specific habitat of F. mexicana. The species is harvested locally for self consumption but the effects of this on its populations is unknown.
Habitat conservation, global warming attenuating actions, and fire control are the main in situ conservation actions. However, since F. mexicana is a saprobe, germoplasm conservation should be desirable. Fruit body culture also could reduce the pressure on natural populations subjected to collection (Arana-Gabriel et al 2014).
Current initatives of exsitu germplasm conservation and fruitbody production for commercial purposes (Arana-Gabriel et al 2014) should be supported and extended.
This species is a valued non timber forest product in the central part of the Transmexican Volcanic Belt. There, local people collect it for self consumption and small scale commerce. It is particularly valued in the Nevado de Toluca volcano.
Arriaga, L., & Gómez, L. (2004). Posibles efectos del cambio climático en algunos componentes de la biodiversidad de México. Cambio climático: una visión desde México, 253-263.
Hughes, K. W., McGhee, L. L., Methven, A. S., Johnson, J. E., & Petersen, R. H. (1999). Patterns of geographic speciation in the genus Flammulina based on sequences of the ribosomal ITS1-5.8 S-ITS2 area. Mycologia, 978-986.
Redhead, S. A., Estrada-Torres, A., & Petersen, R. H. (2000). Flammulina mexicana, a new Mexican species. Mycologia, 1009-1018.
Arana-Gabriel, Y., Burrola-Aguilar, C., Garibay-Orijel, R., & Franco-Maass, S. (2014). Obtención de cepas y producción de inóculo de cinco especies de hongos silvestres comestibles de alta montaña en el centro de México. Revista Chapingo. Serie ciencias forestales y del ambiente, 20(3), 213-226.
Petersen, R. H., Hughes, K. W., Redhead, S. A., Psurtseva, N., & Methven, A. S. (1999). Mating systems in the Xerulaceae (Agaricales, Basidiomycotina): Flammulina. Mycoscience, 40(5), 411-426.
GBIF.org (9th February 2018) GBIF Occurrence Download https://doi.org/10.15468/dl.hnpeao