Lactifluus chiapanensis is an ectomycorrizal fungus only known from the type locality and surroundings, in the Central Depression of Chiapas, south Mexico despite 23 year of exploration in the area.
No additional records have been made in the distribution areas of its potential ectomycorrhizal host, no matter such areas have been extensively explored. Additional studies at worldwide level (De Crop et al. 2017) neither have recorded this species from other regions.
The vegetation canopy in the localities where the species is known is currently under severe fragmentation because of surrounding urban areas development. In the area Gymnopodium floribundum is monodominant. The distribution of this shrub is restricted to some points in southern Mexico and Belize, and a smaller area in Guatemala (GBIF). The populations of L. chiapanensis and G. floribundum concurring in the Central Depression of Chiapas, however, are isolated from the rest of populations of the later because of the Chiapan-Guatemalan Highlands (GBIF, Mastretta-Yanez et al. 2005). Furthermore, L. chiapanensis is an edible species, recollected and sold in the type locality and surroundings (Bandala et al. 2014). The previously mentioned effects of change of land use in its habitat, together with its harvesting for consume, and local sold, could be factors exerting pressure to its populations.
Lactifluus chiapanensis has not been recorded in any other area where it host is distributed, despite more than two decades of continuous exploration in the area, considering this, it can be assumed that the known localities are the only existing localities for the species. The known locality is privately owned, and is surrounded by urban areas.
Considering its very restricted population size, and considering the absence of data regarding trend in population reduction, this species should be listed as Vulnerable under criteria D2, because of its very reduced number of known localities.
Also it fits the criteria A4d because of a continuous reduction in the past, present and future in its population size because of habitat loss and trade levels.
Lactarius chiapanensis was first described by Montoya et al. (1996), and further phyllogenetic studies discovered its close relationship with Lactarius panuoides and L. clarkeae (Stubee et al. 2010). After the segregation of Lactifluus from Lactarius, its position in the former genus was recognized, under subgenus Gymnocarpi, and combined as Lactifluus chiapanensis (Montoya, Bandala & Guzmán) De Crop (De Crop et al. 2017). None other additional records of Lactifluus chiapanensis have been made, neither treated under another name.
The species is recognized by greyish-brown to dirty whitish basidiomes, up to 60 mm in diameter; white latex staining brownish. This species is morphollogically similar to Lactarius petersenii, and L. pseudogerardii, but it can be differentiated because a combination of characters of spore morphology and habitat.
This species is only known from the type locality and the very near surrounding areas, and it has not been located in other areas despite two decades of continuous explorations. The species is considered to establish ectomychorrizal associations with Gymnopodium floribundum, which is the monodominant plant species in the locality. The only locality where the species is known, is a private owned area, surrounded by urban developments, and under severe pressure because of human activities and urban development. This species is reported as consumed and traded by local people since the early 1950. Considering its limited distribution, its specificity in association, and the additional pressures from human activities (including consumption and trade), Lactifluus chiapanensiss is considered vulnerable under criteria D2, because of its very reduced number of known localities. It also fits the criteria A4d because of a continuous reduction in the past, present and future in its population size because of habitat loss and trade levels.
Lactifluus chiapanensis is known from the type locality of Copoya, Tuxtla Gutierrez, Chiapas, Mexico and surroundings (Montoya et al. 1996) aprox at 500 m.a.s.l. in the Central Depression of Chiapas, southern Mexico. The locality is covered with a small patch of tropical deciduous forest, dominated by Gymnopodium floribundum. The land is privately owned, surrounded by growing urban settlements. After its original description, L chiapanensis has been recorded in subsequent explorations in 2003-2008 (Bandala et al. 2011, 2014) and later from 2009-2015, in the same area. As mentioned above, the populations of L. chiapanensis and its putative phytobiont, Gymnopodium floribundum concurring in the Central Depression of Chiapas, appear isolated from the rest of populations of this shrub species (in some points of southern Mexico and Belize, and a smaller area in Guatemala) because of the Chiapan-Guatemalan Highlands (GBIF, Mastretta-Yanez et al. 2005). This species do not have additional records, even after several explorations have been conducted in the same vegetation type.
After first record of Lactifluus chiapanensis, it is only known form the type locality and surroundings areas, with specimens collected in 2003-2008 (Bandala et al. 2011, 2014) and later from 2009-2015, but it has not been registered elsewhere. The land of type locality is privately owned, and is covered with a tropical forest patch dominated by Gymnopodium floribundum. The locality is currently under severe pressure from urban settlements. Because forest type in the known locality is dominated by Gymnopodium floribundum, an ectomycorrhizal shrub, we assume it as the putative ectomycorrhizal host of L. chiapanensis.
The Chiapan-Guatemalan Highlands (GBIF, Mastretta-Yanez et al. 2005) represent a natural barrier, between the populations of G. floribundum occurring in the Central Depression of Chiapas and other populations of this shrub in some points of Yucatan Peninsula, Belize and a smaller area in Guatemala. After several explorations developed by mycologists in the areas mentioned previously, L. chiapanensis has not been recorded elsewhere. Even recent studies on Lactifluus, which have included samples of the genus worldwide, such as De Crop et al. (2017) have considered this species only from the same area in Chiapas. We assume that the number of individuals of L. chiapanensis in the tropical forest patches in Chiapas, which hosts the potential phytobiont, Gymnopodium floribundum, could reach around 1000 individuals. Taking into consideration that i) the tropical forest in the type locality is being under strong urban pressures, ii) the use of L. chiapanensis as an edible fungus, which is even sold locally; and in the absence of additional records elsewhere, iii) its apparently isolated distribution in the Central Depression of Chiapas, L. chiapanensis could be considered as vulnerable.
Population Trend: Uncertain
Lactifluus chiapanensis grows in tropical deciduous forest, dominated by Gymnopodium floribundum (Polygonaceae). Lactifluus is an ectomycorrhizal genus, and we assume that L. chiapanensis establishes ectomycorrhizal associations with G. floribundum because we have confirmed that this shrub forms ectomycorrhizas (Bandala et al. 2011).
After the description of Lactifluus chiapanensis in 1996, we have visited the type locality during subsequent explorations in 2003-2008 (Bandala et al. 2011, 2014) and later from 2009-2015, and have observed that the tropical forest where the species occurs has been continuously fragmented due to the increasing of the surrounding urban area. This fact together with the use of this species as an edible fungi, without a regulated management and its local sale, yearly during its fructification period, could represent severe threats to the only known population of this species, which as mentioned above, appears concurring with G. floribundum in an isolated area, in the Central Depression of Chiapas, South of Mexico.
There are no reports about conservation actions on this species, its area of distribution known occurs in privately owned land. Conservation actions may include the preservation of the vegetation in the area.
Additional information is needed regarding ecology and trophic status. The species is suspected to be ectomycorrhizal, but additional information is needed regarding the association. Also additional research is needed to verify its distribution, and extend its known range.
Lactifluus chiapanensis is an edible mushroom, harvested in the type locality and surroundings, without regulated norms, by local people and sold there and surroundings in the region of Tuxtla Gutierrez, Chiapas, Mexico.
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