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Home/Species/ Van Zuuk's False Bindweed

Calystegia vanzuukiae

Brummitt & Namoff

Van Zuuk's False Bindweed

G2Imperiled Found in 1 roadless area NatureServe Explorer →
G2ImperiledGlobal Rank
MediumThreat Impact
Identity
Unique IDELEMENT_GLOBAL.2.925248
Element CodePDCON040Q0
Record TypeSPECIES
ClassificationSpecies
Classification StatusStandard
Name CategoryVascular Plant
Endemicendemic to a single state or province
KingdomPlantae
PhylumAnthophyta
ClassDicotyledoneae
OrderSolanales
FamilyConvolvulaceae
GenusCalystegia
Concept Reference
Brummitt, R.K. and S.M. Namoff. 2013. Calystegia vanzuukiae (Convolvulaceae), a remarkable new species from central California. Aliso 31:15-18.
Taxonomic Comments
Calystegia vanzuukiae is similar to, but morphologically distinct from, C. stebbinsii and C. occidentalis; phylogenetic evidence suggests it could be of hybrid origin (Brummit and Namoff 2013).
Conservation Status
Rank Method Rank calculation - Biotics v2
Review Date2020-11-06
Change Date2014-08-04
Edition Date2020-11-06
Edition AuthorsTomaino, A. (2020)
Threat ImpactMedium
Range Extent250-1000 square km (about 100-400 square miles)
Number of Occurrences6 - 20
Rank Reasons
Calystegia vanzuukiae is endemic to central California where it is known from Placer and Eldorado counties. Thirteen occurrences are known. Threats include logging, recreation, and non-native plants. It is probably a stabilized hybrid.
Range Extent Comments
Calystegia vanzuukiae is known only from the western Sierra Nevada of central California (Brummitt and Namoff 2013).
Occurrences Comments
There are 13 occurrences in the CNDDB Database (as of November 2020).
Threat Impact Comments
Threats include logging, ORVs, recreation, non-native plants, trails, and roads (CNDDB 2020; CNPS 2020).
Ecology & Habitat

Habitat

Habitat is chaparral and open mixed conifer forests on serpentine and gabbro soils (Brummitt and Namoff 2013). Classified as broadly endemic to serpentine (85-94% of occurrences on serpentine) by Safford and Miller (2020). The habitat of this species has primarily been mapped as Californian Montane Conifer Forest & Woodland (G344), Californian Broadleaf Woodland & Savanna (G195), and Californian Xeric Chaparral (G257), habitat also has been mapped as Sierra-Cascade Red Fir - Mountain Hemlock Forest (G749) and Western Montane Chaparral (G282) at the group level of the US National Vegetation Classification (NatureServe 2025).
Terrestrial Habitats
Forest/WoodlandForest - ConiferWoodland - ConiferShrubland/chaparral
Other Nations (1)
United StatesN2
ProvinceRankNative
CaliforniaS2Yes
Threat Assessments
ThreatScopeSeverityTiming
5 - Biological resource useRestricted (11-30%)Serious - moderate—
5.3 - Logging & wood harvestingRestricted (11-30%)Serious - moderate—
6 - Human intrusions & disturbanceRestricted (11-30%)Moderate or 11-30% pop. decline—
6.1 - Recreational activitiesRestricted (11-30%)Moderate or 11-30% pop. decline—
8 - Invasive & other problematic species, genes & diseasesLarge (31-70%)Moderate or 11-30% pop. decline—
8.1 - Invasive non-native/alien species/diseasesLarge (31-70%)Moderate or 11-30% pop. decline—

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Plant Characteristics
DurationPERENNIAL
Economic Value (Genus)No
Roadless Areas (1)
California (1)
AreaForestAcres
North Fork Middle Fork American RiverTahoe National Forest11,245
References (4)
  1. Brummitt, R.K. and S.M. Namoff. 2013. Calystegia vanzuukiae (Convolvulaceae), a remarkable new species from central California. Aliso 31:15-18.
  2. California Native Plant Society (CNPS). 2020. Inventory of Rare and Endangered Plants (online edition, v8-03 0.39). California Native Plant Society, Sacramento, CA. Online. Available: http://www.rareplants.cnps.org (accessed 2020).
  3. California Natural Diversity Database (CNDDB). 2020. RareFind Version 5.2.14. California Department of Fish and Game, Sacramento.
  4. Safford, H., and J.E.D. Miller. 2020. An updated database of serpentine endemism in the California flora. Madroño 67(2): 85-104.