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Malaxis monophyllos

(L.) Sw.

White Adder's-mouth Orchid

G5Secure Found in 11 roadless areas NatureServe Explorer →

G5SecureGlobal Rank

UnknownThreat Impact

Identity

Unique IDELEMENT_GLOBAL.2.147000

Element CodePMORC1R060

Record TypeSPECIES

ClassificationSpecies

Classification StatusStandard

Name CategoryVascular Plant

CITESAppendix II

Endemicoccurs (regularly, as a native taxon) in multiple nations

KingdomPlantae

PhylumAnthophyta

ClassMonocotyledoneae

OrderOrchidales

FamilyOrchidaceae

GenusMalaxis

Synonyms

Malaxis monophylla(L.) Sw.

Other Common Names

Malaxis monophylle (FR)

Concept Reference

Hulten, E. 1968. Flora of Alaska and neighboring territories. Stanford Univ. Press, Palo Alto, CA. 1008 pp.

Taxonomic Comments

This record represents Malaxis monophyllos in the broad sense following FNA (vol. 26, 2002) that includes M. monophyllos var. monophyllos (including M. diphyllos), and M. monophyllos var. brachypoda. In contrast, Kartesz (1994, 1999) recognized M. diphyllos and M. brachypoda as distinct species (and M. monophyllos sensu stricto as a species but one not occurring in North America).

Conservation Status

Rank Method Rank calculation - Biotics v2

Review Date2025-01-27

Change Date1994-05-04

Edition Date2025-01-27

Edition AuthorsN. Ventrella (2025)

Threat ImpactUnknown

Range Extent>2,500,000 square km (greater than 1,000,000 square miles)

Number of Occurrences> 300

Rank Reasons

Malaxis monophyllos is a perennial orchid occurring swamps, bogs, fens, conifer woods, and dry slopes in the temperate Northern Hemisphere, from North America through Eurasia. There are estimated to be over 1,900 occurrences of this taxon, which are potentially threatened by habitat loss and degradation due to invasive species, development, rights-of-way construction and maintenance, alteration of wetland hydrology, and other threats in some places. Little is known about trends, but with a large range extent, a high number of occurrences, abundant habitat, broad habitat preferences, and no obvious intrinsic vulnerabilities, Malaxis monophyllos is considered secure.

Range Extent Comments

Malaxis monophyllos is a circumboreal species, occurring in the temperate Northern Hemisphere from North America through Eurasia (FNA 2002, POWO 2025). In North America, this species occurs from Alaska and the Northwest Territories southeast across Canada to Newfoundland and Labrador, south to Pennsylvania, Tennessee, and Indiana through Minnesota in the United States. It is disjunct in Colorado, California, and Washington. Range extent was estimated using herbarium specimens, photo-based observations, and NatureServe Network occurrence data collected between 1994 and 2025 (GBIF 2025, iNaturalist 2025, SEINet 2025).

Occurrences Comments

By applying a 1 km separation distance to herbarium records and photo-based observations documented between 1994 and 2025, there are estimated to be over 1,900 occurrences rangewide (GBIF 2025, iNaturalist 2025, SEINet 2025).

Threat Impact Comments

Although threats are not widely documented, Malaxis monophyllos is potentially threatened by habitat loss and degradation due to invasive species, development, rights-of-way construction and maintenance, alteration of wetland hydrology, and other threats in some places.

Ecology & Habitat

Habitat

In North America, Malaxis monophyllos occurs in shaded and open bogs, swamps, conifer woods, and on moist or dry slopes and banks from 0-400 m in elevation (FNA 2002).

Terrestrial Habitats

Woodland - Conifer

Palustrine Habitats

FORESTED WETLANDBog/fen

Other Nations (2)

CanadaN4

Province	Rank	Native
Quebec	SNR	Yes
Ontario	S4	Yes
Labrador	SNR	Yes
New Brunswick	S1	Yes
British Columbia	SNR	Yes
Prince Edward Island	S1	Yes
Island of Newfoundland	S3	Yes
Saskatchewan	S3	Yes
Manitoba	S2	Yes
Nova Scotia	S1	Yes
Yukon Territory	S2	Yes
Northwest Territories	S2	Yes
Alberta	S3	Yes

United StatesN5

Province	Rank	Native
New York	SNR	Yes
Indiana	SNR	Yes
Illinois	SNR	Yes
Minnesota	SNR	Yes
Vermont	S2	Yes
Maine	SNR	Yes
New Hampshire	SNR	Yes
Connecticut	SNR	Yes
Michigan	SNR	Yes
Pennsylvania	SNR	Yes
Washington	SNR	Yes
Wisconsin	SNR	Yes
Massachusetts	SNR	Yes
Tennessee	SNR	Yes
Alaska	S3	Yes
California	SNR	Yes
Colorado	S1	Yes

Threat Assessments

Threat	Scope	Severity	Timing
Unknown/undetermined	—	—	—

Plant Characteristics

DurationPERENNIAL

Economic Value (Genus)No

Roadless Areas (11)

Alaska (11)

Area	Forest	Acres
Chilkat-West Lynn Canal	Tongass National Forest	199,772
Douglas Island	Tongass National Forest	28,065
East Mitkof	Tongass National Forest	8,795
Juneau Urban	Tongass National Forest	101,581
Keku	Tongass National Forest	10,869
Kogish	Tongass National Forest	65,216
North Kruzof	Tongass National Forest	33,146
Rhine	Tongass National Forest	23,010
South Kruzof	Tongass National Forest	55,193
Taku-Snettisham	Tongass National Forest	664,928
Thorne River	Tongass National Forest	72,983

References (10)

Flora of North America Editorial Committee (FNA). 2002a. Flora of North America north of Mexico. Vol. 26. Magnoliophyta: Liliidae: Liliales and Orchidales. Oxford Univ. Press, New York. xxvi + 723 pp.
Global Biodiversity Information Facility (GBIF). 2025. Global Biodiversity Information Facility (GBIF) data portal. Online. Available: https://www.gbif.org/ (accessed 2025).
Hulten, E. 1968. Flora of Alaska and neighboring territories. Stanford Univ. Press, Palo Alto, CA. 1008 pp.
iNaturalist. 2025. Online. Available: https://www.inaturalist.org (accessed 2025).
Kartesz, J.T. 1994. A synonymized checklist of the vascular flora of the United States, Canada, and Greenland. 2nd edition. 2 vols. Timber Press, Portland, OR.
Kartesz, J.T. 1999. A synonymized checklist and atlas with biological attributes for the vascular flora of the United States, Canada, and Greenland. First edition. In: Kartesz, J.T., and C.A. Meacham. Synthesis of the North American Flora, Version 1.0. North Carolina Botanical Garden, Chapel Hill, N.C.
Luer, C.A. 1975. The native orchids of the United States and Canada excluding Florida. New York Botanical Garden. 361 pp.
North American Orchid Conservation Center (NAOCC). 2025. Go Orchids. Online. Available: http://goorchids.northamericanorchidcenter.org/ (accessed 2025).
Plants of the World Online (POWO). 2025. Plants of the World Online. Facilitated by the Royal Botanic Gardens, Kew. Online. Available: https://powo.science.kew.org/ (accessed 2025).
Southwest Environmental Information Network (SEINet). 2025. Collections Databases. Online. Available: https://swbiodiversity.org/seinet/collections/index.php (accessed 2025).

Malaxis monophyllos

Habitat

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