Hedeoma todsenii

Irving

Todsen's False Pennyroyal

G2Imperiled Found in 1 roadless area NatureServe Explorer →
G2ImperiledGlobal Rank
High - mediumThreat Impact
Identity
Unique IDELEMENT_GLOBAL.2.156973
Element CodePDLAM0M0H0
Record TypeSPECIES
ClassificationSpecies
Classification StatusStandard
Name CategoryVascular Plant
Endemicendemic to a single state or province
KingdomPlantae
PhylumAnthophyta
ClassDicotyledoneae
OrderLamiales
FamilyLamiaceae
GenusHedeoma
Other Common Names
Todsen's false pennyroyal (EN)
Concept Reference
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.
Conservation Status
Rank Method Rank calculation - Biotics v2
Review Date2024-07-01
Change Date1991-03-25
Edition Date2024-07-01
Edition AuthorsRoth, E.; rev. DeBruin, E., 1996., rev. A. Treher (2012), rev. N. Ventrella (2024)
Threat ImpactHigh - medium
Range Extent1000-5000 square km (about 400-2000 square miles)
Number of Occurrences6 - 20
Rank Reasons
Hedeoma todsenii is a edaphic perennial herb occurring on gypseous-limestone soils in pinyon-juniper, ponderosa pine, and Douglas fir communities of western North America, where it is found in the San Andres and Sacramento Mountains of southern New Mexico. It is known from approximately eleven occurrences (47 populations), ranging from a few thousand to several dozen plants, occurring primarily on federally-managed lands. This species is threatened by fire suppression and increasing density of pinyon-juniper woodlands, wildfire, and drought due to climate change. Hedeoma todsenii also has some significant intrinsic vulnerabilities; including, low flowering frequency and inbreeding depression that is likely contributing to low seed set.
Range Extent Comments
Hedeoma todsenii occurs in western North America, where it is found in Sierra and Otero counties of southern New Mexico in the San Andres Mountains and Sacramento Mountains (McDonald 1999). Range extent was estimated to be 1,489 square kilometers using herbarium specimens and NatureServe network occurrence data collected between 1978 and 2015 (NatureServe 2024, SEINet 2024). Historic (pre-1993) population locations were used, as all known populations in the San Andres Mountains and most of the populations in the Sacramento Mountains have been verified as extant since at least 2017 (USFWS 2022).
Occurrences Comments
As of 2022, a total of 47 Hedeoma todsenii populations were documented: 32 in the Sacramento Mountains, and an additional fifteen populations in the San Andres Mountains (USFWS 2022). By applying a 1 km separation distance to population location data from herbarium specimens and NatureServe network occurrence data documented between 1978 and 2015, there are eleven estimated occurrences (NatureServe 2024, SEINet 2024). The New Mexico Natural Heritage Program tracks seven occurrences of this species (NatureServe 2024),.
Threat Impact Comments
Hedeoma todsenii populations are potentially threatened by trampling and habitat degradation due to livestock grazing and expanded military activities in the White Sands Missile Range, and also insect herbivory (Britt 2018, USFWS 2001). Forests surrounding populations are becoming increasingly dense due to a history of fire prevention, which increases the risk of catastrophic fire, and potentially impairs flowering due to increased shading (USFWS 2022). Increased severity and frequency of drought conditions expected under climate change will likely adversely impact this species, either directly, or indirectly through impacts to this species primary pollinator, the broad-tailed hummingbird.
Ecology & Habitat

Habitat

Hedeoma todsenii occurs in open pinyon-juniper woodlands usually on north and east-facing slopes with loose, gypseous-limestone soils from 1,900-2,300 m in elevation (McDonald 1999). It also occurs in ponderosa pine and Douglas fir woodlands of the Sacramento Mountains. Other common associated species include Cercocarps montanus, Garrya flavescens, Quercus undulata, Hymenopappus radiatus, Gutierrezia sp., and Muhlenbergia sp. (USFWS 2001)

Reproduction

Hedeoma todsenii spreads via rhizomes and also through sexual reproduction, though plants typically have a low seed set which seems to be a genetic characteristic of the species (USFWS 2011). Within populations measuring up to thousands of clumps, only about 20% will flower, and of that 20%, seed set only occurs in approximately 25-27% (USFWS 2001). Low germination rates have also been recorded for this species (as low as 5% in one study). Nutlets remain inside the calyx which has a mucilaginous surface when wet. The sticky calyx sticks to surfaces, therefore limiting long distance dispersal.
Terrestrial Habitats
Forest/WoodlandWoodland - Conifer
Other Nations (1)
United StatesN2
ProvinceRankNative
New MexicoS2Yes
Threat Assessments
ThreatScopeSeverityTiming
6 - Human intrusions & disturbanceLarge (31-70%)Moderate - slightModerate - low
6.2 - War, civil unrest & military exercisesLarge (31-70%)Moderate - slightModerate - low
7 - Natural system modificationsPervasive (71-100%)Moderate or 11-30% pop. declineHigh (continuing)
7.1 - Fire & fire suppressionPervasive (71-100%)Moderate or 11-30% pop. declineHigh (continuing)
7.1.2 - Suppression in fire frequency/intensityPervasive (71-100%)Moderate or 11-30% pop. declineHigh (continuing)
8 - Invasive & other problematic species, genes & diseasesPervasive - restrictedNegligible or <1% pop. declineHigh (continuing)
8.2 - Problematic native species/diseasesPervasive - restrictedNegligible or <1% pop. declineHigh (continuing)
11 - Climate change & severe weatherPervasive (71-100%)Moderate or 11-30% pop. declineHigh (continuing)
11.2 - DroughtsPervasive (71-100%)Moderate or 11-30% pop. declineHigh (continuing)

Plant Characteristics
DurationPERENNIAL
Economic Value (Genus)No
Roadless Areas (1)
New Mexico (1)
AreaForestAcres
CulpLincoln National Forest3,251
References (12)
  1. Britt, C. 2018. Endangered Species Management Component for Todsen’s Pennyroyal (<i>Hedeoma todsenii</i>) at White Sands Missile Range, New Mexico. Unpublished report prepared for the U.S. Army, White Sands Missile Range, Directorate of Public Works, Environment Division, White Sands Missile Range, New Mexico. 45 pp.
  2. 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.
  3. McDonald, C. 1999. 2009 last update. H<i>edeoma todsenii</i> (Todsen's Pennyroyal). New Mexico Rare Plants. Online. Available: https://nmrareplants.unm.edu/node/93 (accessed 2024).
  4. NatureServe. 2024. NatureServe Network Biodiversity Location Data. NatureServe, Arlington, Virginia.
  5. New Mexico Native Plant Protection Advisory Committee. 1984. A handbook of rare and endemic plants of New Mexico. Univ. New Mexico Press, Albuquerque. 291 pp.
  6. Philpott, M. 2018. The Genetic Consequences of Ex Situ<i> </i>Conservation of Exceptional Plant Species. Unpublished dissertation submitted to the University of Cincinnati, Department of Biological Sciences, Cincinnati, Ohio. 131 pp.
  7. Sivinski, R., and K. Lightfoot. 1994. Todsen's pennyroyal performance report (E9). U.S. Fish and Wildlife Service, Albuquerque, New Mexico.
  8. Southwest Environmental Information Network (SEINet). 2024. Collections Databases. Online. Available: https://swbiodiversity.org/seinet/collections/index.php (accessed 2024).
  9. U.S. Fish and Wildlife Service (USFWS). 1981. Determination of two New Mexico plants to be endangered species and threatened species, with critical habitat. Federal Register 46(12): 5730-5733.
  10. U.S. Fish and Wildlife Service (USFWS). 2001d. Todsen's Pennyroyal<i> (Hedeoma todsenii) </i>Revised Recovery Plan<i>. </i>U.S. Fish and Wildlife Service<i>, </i>Albuquerque, New Mexico. Online. Available: <u></u> (Accessed 2011).
  11. U.S. Fish and Wildlife Service (USFWS). 2011h. Todsens pennyroyal (<i>Hedeoma todsenii</i>) 5-Year Review: Summary and Evaluation. USFWS, Region 2, Ecological Services Field Office, Albuquerque, New Mexico.
  12. US Fish and Wildlife Service (USFWS). 2022. Todsens pennyroyal (<i>Hedeoma todsenii</i>) 5-Year Review: Summary and Evaluation. USFWS, Region 2, Ecological Services Field Office, Albuquerque, New Mexico. 42 pp.