Destuntzia saylorii is a rare, hypogeous fungus, known from three sites in California, USA; one in Tahoe National Forest, and two close to each other in San Bernardino National Forest. Despite multiple attempts to recollect it at the type locality, it went 33 years before being recollected by M. Castellano and N. Siegel in 2019 (personal communication). Being a hypogeous fungus, its detectability is low and relatively few people search for these fungi in the suspected range. Thus is difficult to estimate the population size. While it has a large potential distribution—southern to northern California— it has only been recorded from the extremes of this distribution. Additionally, given the very few recorded sightings of the species over the past 30+ years, the species is considered very rare. Taking a precautionary approach, it is conservatively estimated that the species occurs in up to 50 times the number of known sites (150), each with up to 6 mature individuals, resulting in a estimated population size of up to 900 mature individuals. It is assessed as Vulnerable.

This species is very rare, known from only three locations in California, USA; one in the northern Sierra Nevada, and two in the San Bernardino mountains in southern California.

Currently this species is known from three sites, two in the San Bernardino mountains in southern California and the type location in the northern Sierra Nevada (Siegel et al. 2019). Six collections were made at the type locality in the early and mid 1980’s (MycoPortal 2020). Despite multiple attempts to recollect it at this site, it went 33 years before being recollected by M. Castellano and N. Siegel in 2019 (personal communication). Destuntzia rubra is nearly identical macromorphologically, is listed as a sensitive species by the USDA Forest Service (Castellano et al. 1999) and subjected to active surveys. Even though D. saylorii is not including on the sensitive species list, because of the similarity in the field, there is a high probability that it would have been collected if found. However, no records of D. saylorii have turned up from those surveys. While it has a large potential distribution—southern to northern California— it has only been recorded from the extremes of this distribution. Additionally, given the very few recorded sightings of the species over the past 30+ years, the species is considered very rare. Taking a precautionary approach, it is conservatively estimated that the species occurs in up to 50 times the number of known sites (150), given the amount of suitable habitat, each with up to six mature individuals resulting in a estimated population size of up to 900 mature individuals.

This species is hypogeous, growing scattered or in clusters in duff and soil in forests with Douglas-fir (Pseudotsuga menziesii), White Alder (Alnus rhombifolia), Incense Cedar (Calocedrus decurrens), and oaks (Quercus spp.). All collections were growing along stream banks. Fruiting is from late spring into fall. It is presumably ectomycorrhizal, but its host species are uncertain. This species is dependent on mycophagy (primarily eaten by small mammals) for spore dispersal.

While little is known regarding this species’ distribution and particular habitat preferences to rigorously assess possible threats, habitat loss and decline in quality likely has reduced appropriate habitat for the species.

There is no use/trade.

Known sites should be protected from management activities, including logging, fuels reduction, or other development and disturbance; and it should be added to the USFS sensitive species list. Surveys for this species, and revisits to the historic sites in southern California are needed to see if subpopulations can be located there. Additionally, there is a need to identify potential hosts, and habitat restrictions of this species.