Michx.
Identity
Unique IDELEMENT_GLOBAL.2.157204
Element CodePMORC1R0A0
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
Other Common Namesgreen adder's-mouth orchid (EN) Malaxis unifolié (FR)
Concept ReferenceKartesz, 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.
Conservation Status
Rank Method Rank calculation - Biotics v2
Review Date2025-08-07
Change Date1984-04-16
Edition Date2025-08-07
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 ReasonsMalaxis unifolia is a perennial orchid occurring in forests, woods, swamps, bogs, barrens, and heathlands of North America south to Central America, Cuba, and the West Indies. In North America, it is found from Manitoba east to Newfoundland Island, Canada, and Maine and Minnesota south to Florida and Texas in the United States and Mexico. There are over 1,000 estimated occurrences of this species rangewide, which are threatened in North America by recreation, succession, timber harvest, habitat conversion, deer browse, invasive species, alteration of hydrology, rights-of-way construction and maintenance, peat mining, and likely other threats in some places. Little is known about and trends, but with a large range extent and large number of occurrences, Malaxis unifolia is considered secure.
Range Extent CommentsMalaxis unifolia occurs from North America south to Central America, Cuba, and the West Indies (FNA 2002, Weakley and the Southeastern Flora Team 2025). In North America, it is found from Manitoba east to Newfoundland Island, Canada, and Maine and Minnesota south to Florida and Texas in the United States and Mexico (FNA 2002). Range extent was estimated to be over 18 million square kilometers using herbarium specimens, photo-based observations, and NatureServe Network occurrence data collected between 1994 and 2025 (GBIF 2025, iNaturalist 2025, NatureServe 2025, RARECAT 2025, SEINet 2025).
Occurrences CommentsBy applying a 1 km separation distance to herbarium specimens, photo-based observations, and NatureServe Network occurrence data documented between 1994 and 2025, it is estimated that there are more than 1,000 occurrences rangewide (GBIF 2025, iNaturalist 2025, NatureServe 2025, RARECAT 2025, SEINet 2025).
Threat Impact CommentsThreats to Malaxis unifolia are not well documented but, in North America, include recreation, succession, timber harvest, habitat conversion, deer browse, invasive species, alteration of hydrology, rights-of-way construction and maintenance, peat mining, and likely other threats in some places (NatureServe 2025). There is insufficient data, including anecdotal accounts, to understand the scope and severity of threats for this taxon.