• Proposed
  • Under Assessment
  • Preliminary Assessed
  • LCAssessed
  • 5Published

Butyriboletus frostii (J.L. Russell) G. Wu, Kuan Zhao & Zhu L. Yang

Search for another Species...

Scientific name
Butyriboletus frostii
Author
(J.L. Russell) G. Wu, Kuan Zhao & Zhu L. Yang
Common names
 
IUCN Specialist Group
Mushroom, Bracket and Puffball
Kingdom
Fungi
Phylum
Basidiomycota
Class
Agaricomycetes
Order
Boletales
Family
Boletaceae
Assessment status
Assessed
Preliminary Category
LC
Proposed by
Ella Frigyik and Katherine Angier
Assessors
Gregory Mueller
Comments etc.
Ella Frigyik and Katherine Angier, Alona Yu. Biketova, James Westrip

Assessment Notes

Justification

Butyriboletus frostii can be found throughout eastern North America, areas of Southwest United States, Mexico, and into Central America. It is considered rare and can be fairly common in eastern North America and Mexico. Its status in Southwest United States and Central America is more uncertain. The slow decline in hardwood forests in some areas of its range may correspond with similar declines in B. frostii. It is assessed as Least Concern


Taxonomic notes

Currently placed within the genus Butyriboletus (Wu et al., 2016). Was moved from the genus, Exudoporus (Vizzini, 2014), and before that from Boletus. There is a subspecies in Florida, Exudoporus frostii floridanus, sufficiently distinct as to be considered separately (Singer, 1947). It remains unclear whether the southern range of B. frostii is the subspecies floridanus, Nuhn et al. (2013) place the records from Costa Rica into this subspecies.


Why suggested for a Global Red List Assessment?

Butyriboletus frostii, commonly known as the “candy apple bolete”, is a mycorrhizal bolete fungus identifiable by its bright red cap and its tubes and pores, which take the place of gills. It is distributed across eastern North America, the southwest of the United States, Mexico, and various parts of Central America. B. frostii uses mainly oak as a substrate, and is threatened by the ongoing decline of oak populations in North America. Because this fungus is mycorrhizal, it is important for maintaining forest health. As such, as oak populations decline, B. frostii will suffer because of the loss of substrate, and the forest in turn will suffer from reduced mycorrhizae. This negative feedback loop means that factors which threaten B. frostii populations are likely intertwined with factors which threaten its forests. There is a need for greater research on B. frostii population size and trends, especially in the more isolated areas of its range (southwest of the United States and Central America).


Geographic range

Butyriboletus frostii can be found throughout eastern North America, areas of Southwest United States, Mexico, and into Central America (Kuo 2020) Aside from Costa Rica, distribution unknown elsewhere in Central America.


Population and Trends

More research is needed on population size and trends. Not considered rare and can be fairly common in eastern North America and Mexico. Its status in Southwest and Central America is more uncertain. Slow decline of hardwood forests in some areas of range may correspond with similar declines in B. frostii.

Population Trend: Decreasing


Habitat and Ecology

Forms mycorrhizal associations with many hardwood trees, particularly oaks (Morris et al., 2009), but also pine (Vozzo, 1961) and Madrone in Mexico (Arora, 1986). It has been reported as common in moderately dense oak forests (Singer, 1947) and on sandy soils (Weber & Smith, 1980). Forms sporocoarps between July and October, producing mushrooms either singly or in groups.

Temperate ForestSubtropical/Tropical Dry ForestSubtropical/Tropical Moist Montane Forest

Threats

The species is threatened by the reduction of substrate available to it, namely oak (Bessette et al. 2017). The oak population of eastern North America is threatened by the impacts of climate change, invasive species, growing deer populations, and sociopolitical land disputes that disrupt adequate land management processes (Dey 2014). Note: species listed in the below IUCN classification threaten oak directly, B. frostii indirectly by harming its substrate. Some additional details about the classifications: 8.1.1 numerous introduced nonnative insect and plant species pose threats to oak populations in eastern North America; 8.1.2 Phytophthora ramorum, Limantria dispar, Agrilus planipennis; 8.2.2 Increase in white deer population, oak decline phenomenon (Dey 2014).

Unintentional effects: large scale (species being assessed is not the target) [harvest]Increase in fire frequency/intensityUnspecified speciesNamed speciesNamed speciesHabitat shifting & alterationDroughts

Conservation Actions

Preservation of old growth oak forests and regeneration of oak populations will help bolster B. frostii by providing sufficient habitat for populations to grow.

Site/area protectionSite/area management

Research needed

More specific research on any direct threats to B. frostii populations would be a useful in addition to the current body of research, as much is already known about indirect threats to B. frostii via reduction of its main substrate: oak. Additionally additional surveys are to needed better understand B. frostii population size and trends, especially in the more isolated areas of its range (southwest of the United States and Central America).

Population size, distribution & trendsThreats

Use and Trade

B. frostii is an edible mushroom harvested by foragers. It is described as having a fruity taste (Alabama Mushroom Society, 2018).

Food - human

Bibliography


Country occurrence

Regional Population and Trends

Country Trend Redlisted