We assume that Tylopilus subniger should not have more than 200 subpopulations with 500 mature individuals each. In consequence T. subniger should be listed as Vulnerable under criteria C1 as it has less that 10000 projected mature individuals and the population size will decrease at least 10% in the following 50 years.

This mushroom is a large distinctive bolete characterized by its blackish dry and subtomentose pileus that becomes violet brown. The pores first are white then become grayish or brownish. The stipe is fuligineous or dark chocolate, rarely staining yellow at the base, with a reticulation reaching down the to lower third of the stipe.

Tylopilus subniger is a conspicuous and rare netropical bolete. Its rarity is not a result of under-sampling as it is easily distinguishable and the Neotropical boletes have been already monographed (Singer et al 1991). The especies is associated to mountain cloud forests and tropical oak forest where its host Quercus oleoides is present. Both, its habitat and its host are threatened, its known subpopulations are scarce and fragmented. We assume that Tylopilus subniger should not have more than 200 subpopulations with 500 mature individuals each. In consequence T. subniger should be listed as Vulnerable under criteria C1 as it has less that 10000 projected mature individuals and the population size will decrease at least 10% in the following 50 years.

The species is only known from South Mexico and Costa Rica, so it may distribute in the whole Central America following the distribution of its host Quercus oleoides.

In Mexico there are two known subpopulations in the state of Veracruz: Huatusco and La Banderilla.
In Cost Rica there are two known subpopulations in San Jose and Cartago.
Considering that it is associated with the tropical oak Quercus oleoides already listed as Near Threatened with declining populations, we assume that because its rarity and the fragmented habitat T. subniger should not have more than 200 subpopulations with 500 mature individuals each.

Solitary. In cloud forest and tropical oak forest. Altitude 500-2300m. Ectomycorrhizal with Quercus oleoides.

Rancho la Pomarrosa, where the species was described is already very fragmented since there are currently crops and only patches of original vegatation remain. In Costa Rica it has been collected in Quercus oleoides and according to the IUCN this species is almost threatened by logging since the value of its wood

To protect the few known subpopulations habitat.

To investigate the extent of potential additional subpopulations.

Singer R, García J, Gómez LD (1991) The Boletineae of Mexico and Central America III. Nova Hedwigia, Beihefte 102:1-99.
Ponce-Reyes R, Reynoso-Rosales HV, Watson EMJ, VanDerWal J, Fuller AR, Pressey LR, Possingham PH (2012) Vulnerability of cloud forest reserves in Mexico to climate change. Nature Climatic Change. 2:448-452. DOI:10.1038/NCLIMATE1453
https://www.iucnredlist.org/species/194209/2304166
GBIF.org (30 September 2019) GBIF Occurrence Download https://doi.org/10.15468/dl.visl3t
Gallagher, G. 2018. Quercus oleoides. The IUCN Red List of Threatened Species 2018: e.T194209A2304166.