Fritillaria atropurpurea (spotted fritillary)

Plate 1 figs. a–h · 8 separate observations

Fritillaria atropurpurea, photographed by Trevor Van Loon — fig. a Trevor Van Loon, CC BY 4.0 / 2022-05-28 / obs. 202254451

Fritillaria atropurpurea, photographed by Dee Shea Himes — fig. b Dee Shea Himes, CC BY 4.0 / obs. 198755881

Fritillaria atropurpurea, photographed by Drew Meyer — fig. c Drew Meyer, CC0 1.0 / obs. 137997888

Fritillaria atropurpurea, photographed by Whitney Brook Matson — fig. d Whitney Brook Matson, CC BY 4.0 / obs. 134410881

Fritillaria atropurpurea, photographed by Nolan Exe — fig. f Nolan Exe, CC BY 4.0 / obs. 134419156

Fritillaria atropurpurea, photographed by mark-groeneveld — fig. h mark-groeneveld, CC BY 4.0 / obs. 84284090

Every figure is a research-grade observation under CC0, CC BY or CC BY-SA, rehosted with the photographer’s name, the licence and the observation it came from. Photographs under a NonCommercial licence are excluded from this site and are never stored, which costs us a great many pictures and is not negotiable.

Native range 13 botanical countries

Native distribution of Fritillaria atropurpurea, after Kew’s World Checklist of Vascular Plants. Introduced, extinct and doubtful records are excluded, so this is where the plant is from, not everywhere it now grows.

Region	TDWG code	Continent
Arizona	ARI	NORTHERN AMERICA
California	CAL
Colorado	COL
Idaho	IDA
Montana	MNT
Nebraska	NEB
Nevada	NEV
New Mexico	NWM
North Dakota	NDA
Oregon	ORE
South Dakota	SDA
Utah	UTA
Wyoming	WYO

Region boundaries approximated from Natural Earth (public domain) and mapped to TDWG World Geographical Scheme for Recording Plant Distributions (WGSRPD) level-3 botanical countries (Brummitt 2001). Indicative, not the official WGSRPD geometry.

Flowering 1,073 in flower of 1,272 examined

75%

89%

90%

57%

Proportion of examined Fritillaria atropurpurea in flower, by month
Month	In flower	Examined	Share	95% interval
Jan	0	0	too few examined
Feb	0	0	too few examined
Mar	2	3	too few examined
Apr	30	40	75%	60% to 86%
May	424	475	89%	86% to 92%
Jun	542	602	90%	87% to 92%
Jul	73	128	57%	48% to 65%
Aug	2	22	9%	3% to 28%
Sep	0	2	too few examined
Oct	0	0	too few examined
Nov	0	0	too few examined
Dec	0	0	too few examined

Peak flowering in Jun. Each bar is the share of Fritillaria atropurpurea observations in which someone actually recorded the reproductive state and found the plant in flower, not the raw number of flowering records. That distinction matters: people observe plants far more in spring than in winter, so a bare count of flowering records partly measures when people go outside. Dividing by the number examined removes that. 1,073 of 1,272 examined observations were in flower, every one of them research grade. The whisker on each bar is a 95% Wilson interval. 7 months have fewer than 5 examined observations, so no proportion is drawn for them. This is still a global aggregate and not a forecast for your garden: the same species flowers on different dates in different hemispheres. Where a species has fewer than 30 flowering records we do not draw this chart at all. Computed from 10.15468/dl.cgje2x.

Where it actually grows measured, from 1,986 observations

Condition	5th percentile	Median	95th percentile
Coldest month, mean daily low	-14.5 °C	-9.3 °C	-3.2 °C
Warmest month, mean daily high	22.1 °C	26.4 °C	30.7 °C
Annual rainfall	304 mm	637 mm	1,632 mm
Rainfall in the driest quarter	30 mm	57 mm	161 mm

It is found where winters bring hard frost. This is not care advice and it is not a forecast. It is a measurement: we sampled the climate at every one of the 1,986 research-grade observations of Fritillaria atropurpurea that carry a coordinate, and this is the range those places actually span. The 5th and 95th percentiles are used rather than the minimum and maximum, because a single cultivated specimen in a heated conservatory should not widen a tropical plant's range to the Arctic.

This is not a hardiness zone. A USDA zone is the average annual extreme minimum temperature. The figure above is the mean daily minimum of the coldest month, which is a different quantity and is typically far warmer. Reading one as the other would place a plant several zones too warm, so we do not publish a hardiness zone, because we do not have one. Climate from CHELSA V2.1 (Karger et al. 2017); occurrences from 10.15468/dl.cgje2x.

Also published as 6 synonyms

A synonym is not an error. It is a record of botanists disagreeing, in print, about where this plant belongs. Each of these was somebody’s considered answer.

Amblirion album (Nutt.) Sweet
Fritillaria adamantina M.Peck
Fritillaria alba Nutt.
Fritillaria atropurpurea var. gracillima (Smiley) D.W.Taylor
Fritillaria gracillima Smiley
Fritillaria linearis J.M.Coult. & Fisher

Sourcesevery claim on this page

World Flora Online Plant List. accepted name, authority, classification. CC0. Retrieved 2026-07-12.
iNaturalist. photographs and flowering annotations, CC0 / CC BY / CC BY-SA only. per photograph. Retrieved 2026-06-27.
Wikidata. common name (P1843), joined on the World Flora Online identifier (P7715). CC0. Retrieved 2026-07-13.
Kew, World Checklist of Vascular Plants (WCVP v16). native distribution by TDWG level-3 botanical country, and life form. CC BY 3.0. Retrieved 2026-06-04.

We publish what we can source and we say so when we cannot. This page has no care advice and no toxicity claim, because we do not yet have those from a source we can cite.