Calypso bulbosa

(L.) Oakes

Fairy Slipper

G5Secure Found in 372 roadless areas NatureServe Explorer →
G5SecureGlobal Rank
UnknownThreat Impact
Identity
Unique IDELEMENT_GLOBAL.2.132752
Element CodePMORC0D010
Record TypeSPECIES
ClassificationSpecies
Classification StatusStandard
Name CategoryVascular Plant
CITESAppendix II
Endemicoccurs (regularly, as a native taxon) in multiple nations
KingdomPlantae
PhylumAnthophyta
ClassMonocotyledoneae
OrderOrchidales
FamilyOrchidaceae
GenusCalypso
Other Common Names
Calypso (EN) Calypso bulbeux (FR) fairy slipper (EN) Venus' Slipper (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.
Taxonomic Comments
Distinct species; var. americana is very similar to var. occidentalis.
Conservation Status
Rank Method Rank calculation - Biotics v2
Review Date2025-07-03
Change Date1990-06-22
Edition Date2025-07-02
Edition AuthorsOgle, Y. (1987), rev. D. Atwood; S. Rooney (1984); rev. L. Morse (2003), rev. N. Ventrella (2025)
Threat ImpactUnknown
Range Extent>2,500,000 square km (greater than 1,000,000 square miles)
Number of Occurrences> 300
Rank Reasons
Calypso bulbosa is a perennial orchid occurring in coniferous forests, mixed forests, and bogs worldwide, in North America, Europe, and Asia. In North America, it is distributed from Newfoundland and Labrador, Canada, and Alaska, United States, south to New York and California, and throughout the Rocky Mountains region. There are over a thousand estimated occurrences of this taxon rangewide, which are threatened by logging, climate change, herbivory, invasive plants, pollinator decline, recreation, livestock, and poaching. Little is known about trends, but with a large range extent, high number of occurrences, abundant habitat, and broad habitat preferences, Calypso bulbosa is considered secure.
Range Extent Comments
Calypso bulbosa is a circumboreal taxon, occurring in North America, Europe, and Asia (NAOCC 2025, POWO 2025). In North America, it is distributed from Newfoundland and Labrador, Canada, and Alaska, United States, south to New York and California, and throughout the Rocky Mountains region (FNA 2002, NAOCC 2025). Range extent was estimated to be over 61 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). See individual entries for distribution details about the two varieties in North America.
Occurrences Comments
By 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 over a thousand occurrences rangewide (GBIF 2025, iNaturalist 2025, NatureServe 2025, RARECAT 2025, SEINet 2025).
Threat Impact Comments
In North America, Calypso bulbosa is primarily threatened by loss of habitat due to logging (NatureServe 2025). Additional threats to the species include climate change-related increases to average annual temperatures, winter and summer temperatures, and growing season length, as well as deer browse, slug herbivory, invasive plants, pollinator decline, recreation, trampling by livestock, and poaching (NatureServe 2025).
Ecology & Habitat

Habitat

In North America, Calypso bulbosa occurs in wet, moist, mesic, and dry shady coniferous forests, mixed forests, and bogs from 0-3100 m in elevation (FNA 2002). It is principally associated with Thuja oxidentalis, often found growing in the shaded duff with little or no herbaceous competition (Caljouw 1981).

Ecology

Calypso bulbosa is apparently intolerant of soil temperatures in excess of 15 C and of canopy cover less than 60% (Caljouw 1981).

Reproduction

Calypso bulbosa grows primarily in the fall and early spring, blooming from late May to late June (Mousely 1924). The evergreen, solitary leaf, emerges in late August, overwinters, and shrivels soon after blooming. Capsules are set in June and July, and soon after there may be no visible signs of this species.
Terrestrial Habitats
Forest - ConiferForest - Mixed
Palustrine Habitats
FORESTED WETLANDBog/fen
Other Nations (2)
CanadaN5
ProvinceRankNative
AlbertaS5Yes
ManitobaS4Yes
QuebecSNRYes
Northwest TerritoriesS4Yes
Yukon TerritoryS3Yes
British ColumbiaS5Yes
SaskatchewanS3Yes
NunavutSHYes
Island of NewfoundlandS1Yes
New BrunswickS2Yes
OntarioS4Yes
United StatesN5
ProvinceRankNative
AlaskaS4Yes
MinnesotaS3Yes
Navajo NationS1Yes
South DakotaS3Yes
VermontSHYes
UtahS4Yes
MaineS3Yes
IdahoSNRYes
CaliforniaSNRYes
New YorkSHYes
WashingtonSNRYes
MontanaS4Yes
ColoradoS4Yes
WisconsinS2Yes
New HampshireSNRYes
ArizonaS3Yes
New MexicoSNRYes
MichiganS2Yes
WyomingS3Yes
OregonSNRYes
Plant Characteristics
DurationPERENNIAL
Economic Value (Genus)No
Roadless Areas (372)
Alaska (18)
AreaForestAcres
ChichagofTongass National Forest555,858
Chilkat-West Lynn CanalTongass National Forest199,772
College FiordChugach National Forest1,130,818
Five MileTongass National Forest19,459
Freshwater BayTongass National Forest44,933
KartaTongass National Forest52,117
KekuTongass National Forest10,869
KogishTongass National Forest65,216
KosciuskoTongass National Forest64,134
Mansfield PeninsulaTongass National Forest54,991
Middle KruzofTongass National Forest14,724
MosmanTongass National Forest53,492
North KruzofTongass National Forest33,146
North KupreanofTongass National Forest114,660
Rocky PassTongass National Forest78,163
Sitka SoundTongass National Forest13,459
South KruzofTongass National Forest55,193
SpiresTongass National Forest533,746
California (38)
AreaForestAcres
Bell QuinbyShasta-Trinity National Forest11,556
Blue Creek Rare ISix Rivers National Forest12,134
Board CampSix Rivers National Forest4,527
Castle Crags AShasta-Trinity National Forest113
Castle Crags BShasta-Trinity National Forest1,619
ChanchelullaShasta-Trinity National Forest3,915
Cow CreekShasta-Trinity National Forest22,627
EagleShasta-Trinity National Forest6,553
East GirardShasta-Trinity National Forest27,894
GriderKlamath National Forest10,647
JohnsonKlamath National Forest10,652
KangarooKlamath National Forest40,617
KellySix Rivers National Forest5,195
Lake EleanorShasta-Trinity National Forest397
Little French CShasta-Trinity National Forest11,529
Monkey CreekSix Rivers National Forest9,017
Mt. Shasta BShasta-Trinity National Forest2,809
North Fork SmithSix Rivers National Forest37,898
Orleans Mtn.Klamath National Forest49,090
Orleans Mtn. BSix Rivers National Forest17,183
Orleans Mtn. CSix Rivers National Forest15,589
PacksaddleSix Rivers National Forest3,862
PattisonShasta-Trinity National Forest29,299
Pilot CreekSix Rivers National Forest9,192
PortugueseKlamath National Forest18,915
RussianKlamath National Forest21,771
ShacklefordKlamath National Forest1,679
Ship MountainSix Rivers National Forest11,936
SiskiyouKlamath National Forest54,039
Siskiyou ASix Rivers National Forest1,017
Siskiyou BSix Rivers National Forest18,871
Slide CreekSix Rivers National Forest11,458
SnoozerKlamath National Forest23,414
SoliderSix Rivers National Forest14,918
South ForkShasta-Trinity National Forest16,786
Weaver BallyShasta-Trinity National Forest829
Wells MountainShasta-Trinity National Forest5,919
West GirardShasta-Trinity National Forest37,516
Colorado (9)
AreaForestAcres
Comanche Peak Adjacent AreaArapaho & Roosevelt NFs44,158
Dome PeakRoutt NF35,716
HermosaSan Juan NF148,103
Long ParkRoutt NF42,100
Pole Mountain / Finger MesaRio Grande NF43,863
Red TableWhite River NF39,122
San MiguelSan Juan NF64,263
Storm PeakSan Juan NF57,617
Troublesome SouthRoutt NF47,359
Idaho (9)
AreaForestAcres
Bear CreekCaribou-Targhee National Forest118,582
Bighorn - WeitasNez Perce-Clearwater National Forest254,845
HoodooNez Perce-Clearwater National Forest153,868
NeedlesPayette National Forest131,279
North Lochsa SlopeNez Perce-Clearwater National Forest117,662
PalisadesCaribou-Targhee National Forest122,002
Peace RockBoise National Forest191,734
SeceshPayette National Forest248,088
West Meadow CreekNez Perce-Clearwater National Forest115,949
Minnesota (1)
AreaForestAcres
Wood LakeSuperior National Forest596
Montana (70)
AreaForestAcres
Allan Mountain (01946)Bitterroot National Forest104,184
Anaconda HillHelena National Forest18,546
Basin CreekBeaverhead-Deerlodge National Forest9,500
Bear - Marshall - Scapegoat - SwanHelena National Forest51,360
Bear - Marshall - Scapegoat - SwanLolo National Forest118,485
Bear - Marshall - Scapegoat - SwanLewis and Clark National Forest344,022
Big BaldyLewis and Clark National Forest43,135
Big Snowy Mountains WsaLewis and Clark National Forest88,003
Black ButteCuster National Forest871
Bluff MountainLewis and Clark National Forest38,060
Bmss Ra 1485Flathead National Forest334,275
BridgerGallatin National Forest45,059
Buckhorn Ridge (MT)Kootenai National Forest34,716
Burnt MountainCuster National Forest10,698
Cabin Creek Wildlife Management Area OcdGallatin National Forest35,048
Cabinet Face East #671Kootenai National Forest50,326
Call MountainBeaverhead-Deerlodge National Forest8,796
Camas CreekHelena National Forest29,191
Continental Divide National Scenic TrailBitterroot National Forest312
Crazy MountainGallatin National Forest82,093
Cube Iron - SilcoxLolo National Forest36,998
East PioneerBeaverhead-Deerlodge National Forest145,082
ElkhornHelena National Forest75,468
Evans GulchLolo National Forest8,059
Flagstaff Mountain #690Kootenai National Forest11,114
Freezeout MountainBeaverhead-Deerlodge National Forest97,305
Gallatin FringeGallatin National Forest51,571
Gold Hill #668Kootenai National Forest6,455
HoodooLolo National Forest105,162
Hyalite - Porcupine - Buffalo Horn Wilderness Study AreaGallatin National Forest143,991
Jerico MountainHelena National Forest8,445
Lazyman GulchHelena National Forest11,614
Lebeau RA 1507Flathead National Forest5,450
Line Creek PlateauCuster National Forest24,825
LionheadGallatin National Forest33,549
Lolo CreekLolo National Forest14,335
MadisonGallatin National Forest127,859
Maple PeakLolo National Forest6,469
Marston Face # 172Kootenai National Forest9,098
Middle Fork Judith WsaLewis and Clark National Forest81,131
Middle Mtn. / Tobacco RootsBeaverhead-Deerlodge National Forest96,487
Mt. BaldyHelena National Forest16,362
Mt. BushnellLolo National Forest41,798
Mt. Gmt Area HCuster National Forest1,335
North AbsarokaGallatin National Forest159,075
North AbsarokaCuster National Forest21,063
North Big HoleBeaverhead-Deerlodge National Forest52,227
North CarpBeaverhead-Deerlodge National Forest6,600
Patricks Knob - North CutoffLolo National Forest16,970
Petty MountainLolo National Forest16,178
QuiggLolo National Forest67,267
Red Lodge Creek HellroaringCuster National Forest17,210
Roderick #684Kootenai National Forest29,677
Saddle Mountain #168Kootenai National Forest14,675
SapphireBitterroot National Forest43,303
SapphiresBeaverhead-Deerlodge National Forest66,619
Scotchman Peaks (MT)Kootenai National Forest53,909
Selway - Bitterroot (01067)Bitterroot National Forest114,953
Silver KingBeaverhead-Deerlodge National Forest64,289
Silver KingLolo National Forest12,816
South Siegel - South CutoffLolo National Forest13,474
Stevens PeakLolo National Forest647
Stony MountainBitterroot National Forest44,057
Ten Lakes #683Kootenai National Forest48,545
Thompson Seton RA 1483Flathead National Forest52,235
Upper East ForkBeaverhead-Deerlodge National Forest8,905
West Big HoleBeaverhead-Deerlodge National Forest133,563
West PioneerBeaverhead-Deerlodge National Forest248,631
Willard Estelle #173Kootenai National Forest3,714
Zulu #166Kootenai National Forest10,010
New Mexico (18)
AreaForestAcres
Black CanyonSanta Fe National Forest1,922
Bull - Of - The - WoodsCarson National Forest488
Canada Bonito RNASanta Fe National Forest487
Canones CreekSanta Fe National Forest3,938
Columbine - Hondo Wilderness Study AreaCarson National Forest43,739
Comales CanyonCarson National Forest4,389
El LagunitoSanta Fe National Forest6,799
Guaje CanyonSanta Fe National Forest6,104
Juan de Gabaldon GrantSanta Fe National Forest8,023
Nichols ReservoirSanta Fe National Forest1,518
Pacheco CanyonSanta Fe National Forest1,012
PecosCarson National Forest13,436
Pecos WS RiverSanta Fe National Forest5,396
Polvadera PeakSanta Fe National Forest6,291
San Pedro ParksSanta Fe National Forest5,824
Tesuque CreekSanta Fe National Forest810
Thompson PeakSanta Fe National Forest33,001
Wheeler Peak WildernessCarson National Forest2,677
Oregon (77)
AreaForestAcres
Badger CreekMt. Hood National Forest847
Bend WatershedDeschutes National Forest14,829
Boulder ParkWallowa-Whitman National Forest12,141
Brown Mt.Winema National Forest3,117
Bull Of The WoodsWillamette National Forest53
Bull Of The WoodsMt. Hood National Forest8,843
Calf - Copeland CreekUmpqua National Forest15,696
Castle Rock AppendageUmpqua National Forest4,649
Chucksney MountainWillamette National Forest15,369
Cook RidgeWallowa-Whitman National Forest19,617
Cougar BluffUmpqua National Forest5,574
Dixie ButteMalheur National Forest12,208
EagleMt. Hood National Forest16,841
Echo MountainWillamette National Forest8,098
ElkhornWillamette National Forest9,380
FairviewUmpqua National Forest7,417
French Pete (a)Willamette National Forest1,668
French Pete (b)Willamette National Forest1,186
Gordon MeadowsWillamette National Forest9,463
Grande RondeUmatilla National Forest12,296
Hardesty MountainWillamette National Forest3,754
Hardesty MountainUmpqua National Forest2,597
HellholeUmatilla National Forest65,679
HomesteadWallowa-Whitman National Forest5,817
Horseshoe RidgeUmatilla National Forest5,996
Hurricane CreekWallowa-Whitman National Forest1,606
Imnaha FaceWallowa-Whitman National Forest29,575
Jaussaud CorralUmatilla National Forest5,535
Joseph CanyonWallowa-Whitman National Forest24,288
Jumpoff JoeUmatilla National Forest5,516
LakeMt. Hood National Forest1,327
LarchMt. Hood National Forest12,961
Lick CreekWallowa-Whitman National Forest1,956
Limpy RockUmpqua National Forest6,782
Little CreekWallowa-Whitman National Forest2,815
Little Eagle MeadowsWallowa-Whitman National Forest6,984
Little SheepWallowa-Whitman National Forest5,238
LookingglassUmatilla National Forest4,859
Maiden PeakWillamette National Forest9,627
MarshWinema National Forest1,226
Mcclellan MountainMalheur National Forest21,213
Mclennon MountainWillamette National Forest8,085
Menagerie (rooster Rock)Willamette National Forest374
Metolius BreaksDeschutes National Forest11,141
Mill Creek Watershed (OR)Umatilla National Forest7,820
Mountain SheepWallowa-Whitman National Forest19,457
Mt. EmilyWallowa-Whitman National Forest8,421
Mt. JeffersonDeschutes National Forest2,282
Mt. BaileyUmpqua National Forest18,401
Mt. HagenWillamette National Forest6,406
Mt. Hood AdditionsMt. Hood National Forest13,061
Nipple ButteMalheur National Forest11,354
North KalmiopsisSiskiyou National Forests91,560
Opal CreekWillamette National Forest5,417
Rainbow FallsWillamette National Forest65
Roaring RiverWillamette National Forest2,128
Roaring RiverMt. Hood National Forest27,316
Salmon - HuckleberryMt. Hood National Forest17,570
Shasta CostaSiskiyou National Forests14,420
Sheep DivideWallowa-Whitman National Forest16,201
SherwoodUmpqua National Forest2,449
Skimmerhorn AppendageUmpqua National Forest1,820
Sky Lakes AWinema National Forest3,940
Sky Lakes BWinema National Forest9,615
Smith UmpquaSiuslaw National Forest7,622
South KalmiopsisSiskiyou National Forests104,477
Texas ButteUmatilla National Forest6,871
Twin LakesMt. Hood National Forest6,055
Twin MountainWallowa-Whitman National Forest58,533
Upper Catherine CreekWallowa-Whitman National Forest6,446
W. BoundaryWinema National Forest2,345
Waldo - FujiWillamette National Forest15,273
Waldo - Many PrariesWillamette National Forest2,585
Waldo - MoolackWillamette National Forest1,183
Walla Walla RiverUmatilla National Forest34,416
Williams CreekUmpqua National Forest5,844
Wind CreekMt. Hood National Forest5,438
South Dakota (1)
AreaForestAcres
Indian CreekBuffalo Gap National Grassland24,666
Texas (1)
AreaForestAcres
Big CreekNational Forests in Texas1,447
Utah (12)
AreaForestAcres
0401001Ashley National Forest11,705
0401002Ashley National Forest36,113
0401014Ashley National Forest26,903
0419020Ashley National Forest355,684
418001Uinta National Forest5,697
418003Uinta National Forest10,912
418004Uinta National Forest16,661
418042Uinta National Forest7,313
High Uintas (UT)Wasatch-Cache National Forest102,398
LakesWasatch-Cache National Forest121,967
Little West Fork BlacksWasatch-Cache National Forest8,209
NoblettsWasatch-Cache National Forest3,116
Washington (72)
AreaForestAcres
Abercrombie - HooknoseColville National Forest33,862
Alpine Lakes Adj.Wenatchee National Forest57,104
BackboneGifford Pinchot National Forest1,201
Bald SnowColville National Forest23,198
Bear CreekGifford Pinchot National Forest7,980
Big Lava BedGifford Pinchot National Forest19,043
Blue LakeGifford Pinchot National Forest11,359
Blue SlideWenatchee National Forest17,505
Boulder RiverMt Baker-Snoqualmie National Forest32,563
BourbonGifford Pinchot National Forest4,512
Canyon CreekWenatchee National Forest7,983
ChambersGifford Pinchot National Forest2,006
ChelanWenatchee National Forest74,650
Clackamas MountainOkanogan National Forest12,478
Dark DivideGifford Pinchot National Forest52,483
Devils GulchWenatchee National Forest24,419
Dixon MountainGifford Pinchot National Forest6,339
EntiatWenatchee National Forest72,617
Glacier Peak BMt Baker-Snoqualmie National Forest19,328
Glacier Peak JMt Baker-Snoqualmie National Forest26,482
Glacier Peak KMt Baker-Snoqualmie National Forest47,269
Goat Rocks AdjWenatchee National Forest6,108
Gotchen CreekGifford Pinchot National Forest7,518
Granite MountainOkanogan National Forest27,428
Grassy TopColville National Forest10,302
Grassy TopIdaho Panhandle National Forests13,485
Green MountainOlympic National Forest4,617
Heather LakeWenatchee National Forest10,628
HoodooColville National Forest7,142
Jackson CreekOkanogan National Forest7,791
Jackson CreekColville National Forest3,003
Jefferson RidgeOlympic National Forest6,512
Jupiter RidgeOlympic National Forest10,148
Laughing WaterGifford Pinchot National Forest1,167
Liberty BellOkanogan National Forest108,495
LightningOlympic National Forest7,179
Lion RockWenatchee National Forest4,692
Long SwampOkanogan National Forest66,344
Madison CreekOlympic National Forest1,223
ManastashWenatchee National Forest11,155
Meadow CreekUmatilla National Forest4,882
Mill Creek Watershed (WA)Umatilla National Forest16,747
Mt. Baker MaMt Baker-Snoqualmie National Forest24,847
Mt. Baker Noisy - DiobsudMt Baker-Snoqualmie National Forest56,039
Mt. Baker NorthMt Baker-Snoqualmie National Forest16,873
Mt. Baker WestMt Baker-Snoqualmie National Forest25,390
Mt. BaldyOlympic National Forest3,557
Mt. BonaparteOkanogan National Forest10,891
Mt. ZionOlympic National Forest3,544
Nason RidgeWenatchee National Forest19,329
Norse PeakWenatchee National Forest10,169
Packwood LakeGifford Pinchot National Forest1,084
Pasayten RimOkanogan National Forest17,074
PompeyGifford Pinchot National Forest23,985
ProfanityColville National Forest28,944
QuartzWenatchee National Forest8,550
QuilceneOlympic National Forest18,656
Rock CreekWenatchee National Forest32,239
Salmo - Priest BColville National Forest11,869
SawtoothOkanogan National Forest122,194
South QuinaultOlympic National Forest11,081
SpanglerUmatilla National Forest5,936
TaneumWenatchee National Forest26,140
TeanawayWenatchee National Forest72,849
Thorp Mtn.Wenatchee National Forest22,717
TumwaterGifford Pinchot National Forest8,676
Twin LakesWenatchee National Forest22,496
Twin SistersColville National Forest13,051
Upper SkokomishOlympic National Forest9,311
Upper TucannonUmatilla National Forest12,485
Wenatchee CreekUmatilla National Forest15,315
Willow SpringsUmatilla National Forest10,414
Wyoming (46)
AreaForestAcres
Bear RocksBighorn National Forest25,023
Beartooth Proposed WildernessShoshone National Forest16,837
Bridger PeakMedicine Bow-Routt National Forest6,697
Buffalo PeakMedicine Bow-Routt National Forest17,560
Cloud Peak ContiguousBighorn National Forest113,757
Cow Creek MountainMedicine Bow-Routt National Forest8,276
Franc's PeakShoshone National Forest68,561
Grayback RidgeBridger-Teton National Forest295,113
Grommund CreekBighorn National Forest12,089
Gros Ventre MountainsBridger-Teton National Forest106,418
Horse Creek MesaBighorn National Forest77,808
Illinois CreekMedicine Bow-Routt National Forest6,711
Laramie PeakMedicine Bow-Routt National Forest28,608
Libby FlatsMedicine Bow-Routt National Forest11,107
Little BighornBighorn National Forest133,949
Little Sheep MountainBridger-Teton National Forest14,192
Monument RidgeBridger-Teton National Forest17,720
Mosquito Lake - Seven LakesBridger-Teton National Forest51,950
Mowry PeakMedicine Bow-Routt National Forest6,244
Pacific Creek - Blackrock CreekBridger-Teton National Forest24,658
PalisadesTarghee National Forest1,121
Pennock MountainMedicine Bow-Routt National Forest9,599
Phillips RidgeBridger-Teton National Forest10,108
Piney CreekBighorn National Forest22,240
Platte River AdditionMedicine Bow-Routt National Forest7,962
ReefShoshone National Forest16,817
Rock CreekBighorn National Forest48,657
Rock CreekMedicine Bow-Routt National Forest18,874
Salt River RangeBridger-Teton National Forest235,661
Savage Run AdditionMedicine Bow-Routt National Forest2,368
Sibley LakeBighorn National Forest10,367
Sleeping GiantShoshone National Forest5,176
Snowy RangeMedicine Bow-Routt National Forest29,660
Solomon CreekMedicine Bow-Routt National Forest5,756
South Beartooth HighwayShoshone National Forest105,570
Spread Creek - Gros Ventre RiverBridger-Teton National Forest166,097
Sulphur CreekShoshone National Forest30,221
Teton Corridor TrailheadsBridger-Teton National Forest286
Walker PrairieBighorn National Forest62,434
Wapiti Valley NorthShoshone National Forest18,345
West Slope TetonsTarghee National Forest47,448
West Slope WindsBridger-Teton National Forest143,252
Wilderness Study AreaTarghee National Forest51,961
Windy MountainShoshone National Forest31,283
Winegar HoleTarghee National Forest247
Wood RiverShoshone National Forest50,638
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