• Proposed
  • Under Assessment
  • Preliminary Assessed
  • Assessed
  • VUPublished

Amanita morrisii Peck

Go to another Suggested Species...

Scientific name
Amanita morrisii
Common names
Morris' Amanita
Amanite de Morris
Amanite des pinèdes
IUCN Specialist Group
Mushroom, Bracket and Puffball
Assessment status
IUCN Red List Category
Proposed by
Annabelle Langlois
Annabelle Langlois
Michael Castellano, Noah Siegel
Anders Dahlberg

Assessment Notes

Associated with Pinus rigida/Pinus sp. in the Pine Barrens in northeastern North America. Expected loss of habitat to urban development is approximately 10% over 50 years (3 generations) according to Nature Conservancy.

Less than 10 000 mature individuals are estimated to exist (14 confirmed sites x 50 (times more sites because probably often misidentified) x 2 functional individuals per site, 5 mature individuals per functional individual because solitary to subgregarious).

Vulnerable (VU) C1.

Taxonomic notes

= Amplariella morrisii (Peck) E.-J. Gilbert
= Venenarius morrisii (Peck) Murrill
= Amanita pinophila Y. Lamoureux nom. prov. in herb?

Peck. 1910. Bull. N. Y. St. Mus. 139: 42.

Why suggested for a Global Red List Assessment?

Amanita morrisii was first described by Peck (1910) and has rarely been found. It generally grows on wet soil in association with pines and even though it is part of a well studied group, the species has been found in only 14 sites in northeastern North America. Its apparent restriction to the Pine Barrens, which are ecosystems that are expected to lose 10% of its area to development within the next 50 years (Nature Conservancy 2016), indicates that A. morrisii population will also decline. Its restriction to wetlands within the Pine Barrens makes habitat loss and habitat quality loss critically threatening to A. morrisii, as water quality and water level is expected to be altered (Pinelands Preservation Alliance 2016).

Geographic range

In the United States, Amanita morrisii is known from Maine (Cumberland Co.), New Jersey (Burlington Co., Ocean Co.), Massachusetts (Barnstable Co., Essex Co., Middlesex Co.), New Hampshire (Carroll Co.; Overholts 1921), maybe New York (Oneida Co.; uncertain identification of specimen) and is expected in neighbouring regions (Tulloss, amanitaceae.org). Its presence is also mentioned in Canada from Quebec province (Laurentides, Monteregie; mycoquebec.org).

Population and Trends

Amanita morrisii is known from only 14 sites across northeastern North America. The species is thought to be declining because of habitat loss due to land development. The Nature Conservancy estimates that if the 1990-2000 rate of loss is maintained, about 10% of the Pine Barrens in northeastern North America (i.e., Northeastern Interior Pine Barrens, North Atlantic Coastal Plain Pitch Pine Lowland and North Atlantic Coastal Plain Pitch Pine Barrens) will be lost to urban development within the next 50 years.

USA : 1 site in Maine (1995), 4 in Massachusetts (1909, 1910, 1911//1927//1995, 2009//2008 twice) 6 in New Jersey (1983//1983//1988//1995, 1997, 2008, 2011, 2013//2009//2009, 2012) and 1 in New Hampshire (prior to 1921). Total 12 sites. There is also 1 uncertain site (specimen has not been thoroughly examined) in New York (2011, 2012). See amanitaceae.org (Tulloss), Overholts 1921 and mushroomobserver.org.
CAN : 2 sites in Quebec province (1997//??). See mycoquebec.org (2015). Also Y. Lamoureux, personal communication.

Amanita morrisii is fairly easy to identify due to its characteristic dark brown cap that fades slightly with age and its annulus with a colored underside. However, and even though it is part of a popular group (Amanita), A. morrisii is not a well-known species. Thus, we believe A. morrisii is rarely overlooked but often misidentified when found.

There are 14 sites where A. morrisii has been found and we estimate that there are probably 50 times more. Each site is thought to represent 2 functional individuals. Each functional individual is expected to represent 5 mature individuals. We estimate the total number of mature individuals of A. morrisii to range between 5 000 and 10 000.

Population Trend: Decreasing

Habitat and Ecology

Amanita morrisii is a mycorrhizal fungus species and is dependent on living host trees for population viability. This mutually beneficial, symbiotic association between fungus and plant host roots conveys numerous critical advantages for plant host survival. Mycorrhizal fungi are essentially the uptake organs for many nutrients i.e., nitrogen, phosphorus, numerous micronutrients, i.e., boron, selenium, copper, and plays a major role in uptake of water. Both the fungus and the plant host do not exist in nature without each other.

Amanita morrisii grows solitary, in pairs, or subgregariously. In Massachusetts, A. morrisii was found in “black vegetable mold” among mosses of swampy area (Natick collections; Tulloss 1991) or in Chamaecyparis thyoides swamp (Barnstable Co. (Cape Cod) collection). In New Jersey, it was found in wet sand (poor in organic matter) of Pinus rigida-Quercus barrens, occasionally with Chamaecyparis thyoides nearby, where soil surface is barely above the level of nearby ponds or lakes (Tulloss, amanitaceae.org). In Chamaecyparis thyoides swamps, there are typically Pinus rigida and Betula populifolia present as well (Laidig and Zampella 1999). In New Hampshire, it was found on the ground in damp woods (Overholts 1921). In Quebec province (Canada), A. morrisii was found on Sphagnum under a natural forest of Pinus rigida and Pinus resinosa in an open area. The soil was thin and composed of Sphagnum on bedrock (indicating poor drainage). In Quebec province (Canada), A. morrisii has also been found with ca. 100 years old Pinus sylvestris, P. resinosa and Picea abies on wet moss over thick hummus and sandy soil in a shaded area (Y. Lamoureux, personal communication).

The common host tree species between these observations is Pinus rigida, which is most common in the Pine Barrens in northeastern North America. Thus, the fate of A. morrisii is linked to the fate of this habitat. Fungus species associated with Pinus rigida are expected to occasionally associate with other Pinus species (Horton and Bruns 1998), which would explain why A. morrisii was found in Quebec where there is P. sylvestris and P. resinosa but no P. rigida.

Wetlands (inland)Bogs, Marshes, Swamps, Fens, Peatlands [generally over 8 ha]


The main threat to A. morrisii is habitat loss and reduction in habitat quality, as the Pine Barrens in northeastern North America are being negatively impacted mostly by development of land (Pinelands Preservation Alliance 2016). Amanita morrisii’s restriction to wetlands within the Pine Barrens makes habitat loss and reduction in habitat quality even more threatening, as water quality and water level is expected to be altered in the Pine Barrens (Pinelands Preservation Alliance 2016). Many historic sites where A. morrisii occurred in urban areas and are now likely extirpated.

Residential & commercial development

Conservation Actions

The species occurs in at least nine protected sites, either in preserves or parks. Other sites where it occurs should be protected as well. Amanita morrisii can be relatively easy to identify and amateur mycologists could significantly contribute in data collection after learning where to find and how to recognize A. morrisii.

Site/area managementEducation & awareness

Research needed

Amanita morrisii should be searched for within-range similar habitats to evaluate population size, distribution and population trend. Sites where the species has not been found for a long period of time should be inventoried first to confirm the actual number of extant A. morrisii sites.

Amanita morrisii is a fairly easily identified species due to its cap color and colored partial veil, but it is not well-known by most mycologists. In northeastern North America, where A. morrisii is found, there are numerous groups of amateur mycologists. Members of these groups can be recruited and instructed where to find and how to identify A. morrisii so they can target this species during forays. Data from amateur mycologists can be critical to define A. morrisii population size, distribution and trends.

Population size, distribution & trendsThreats

Use and Trade


Amanita morrisii. (2014). Retrieved 22 April 2016 from gbif.org
Amanita morrisii. (2015). Retrieved 15 April 2016 from mycoquebec.org.
Horton, T. R., & Bruns, T. D. (1998). Multiple‐host fungi are the most frequent and abundant ectomycorrhizal types in a mixed stand of Douglas fir (Pseudotsuga menziesii) and bishop pine (Pinus muricata). New Phytologist 139 (2): 331-339.
Laidig, K. J., & Zampella, R. A. (1999). Community attributes of Atlantic white cedar (Chamaecyparis thyoides) swamps in disturbed and undisturbed Pinelands watersheds. Wetlands 19 (1): 35-49.
Nature Conservancy. Northeastern Interior Pine Barrens. Retrieved April 26 from conservationgateway.org.
Nature Conservancy. North Atlantic Coastal Plain Pitch Pine Barrens. Retrieved 26 April from conservation gateway.org.
Nature Conservancy. North Atlantic Coastal Plain Pitch Pine Lowland. Retrieved 26 April from conservationgateway.org.
Overholts, L. O. (1921). Some New Hampshire Fungi. Mycologia 13 (1): 24-37.
Pinelands Preservation Alliance. Threats to the Pinelands. Retrieved 26 April 2016 from pinelandsalliance.org.
Smith, E. (2012). Observation 108176: Amanita morrisii Peck. Retrieved 15 April 2016 from mushroomobserver.org
Tulloss, R. E. (1991). Amanita morrisii: history, taxonomy, and distribution. Mycotaxon 40: 281-286.
Tulloss, R. E. Amanita morrisii. Retrieved 15 April 2016 from amanitaceae.org
USDA. (1995). Wetlands Values and Trends. Natural Resources Conservation Service, United States Department of Agriculture. Retrieved 15 April 2016 from nrcs.usda.gov.

Known distribution - countries

Regional Population and Trends

Country Trend Redlisted