Platystemon californicus (creamcups)

Plate 1 figs. a–h

Platystemon californicus, photographed by Arvel Hernandez — fig. a Arvel Hernandez, CC BY 4.0 / 2022-05-06 / obs. 195683448

Platystemon californicus, photographed by Madeleine Claire — fig. b Madeleine Claire, CC BY 4.0 / obs. 194237797

Platystemon californicus, photographed by Marc Whitaker — fig. c Marc Whitaker, CC BY 4.0 / obs. 198683491

Platystemon californicus, photographed by Lori Brandt Dudzik — fig. d Lori Brandt Dudzik, CC BY-SA 4.0 / obs. 191937249

Platystemon californicus, photographed by Steve Woodward — fig. e Steve Woodward, CC0 1.0 / obs. 191395060

Platystemon californicus, photographed by Cricket Raspet — fig. f Cricket Raspet, CC BY 4.0 / obs. 190811761

Platystemon californicus, photographed by Jacquie Villa Rajerison — fig. g Jacquie Villa Rajerison, CC0 1.0 / obs. 188542426

Platystemon californicus, photographed by paulexcoff — fig. h paulexcoff, CC BY-SA 4.0 / obs. 189285040

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.

Flowering n = 2,059 observations

645

916

339

Flowering observations of Platystemon californicus by month
Month	Observations
Jan	0
Feb	57
Mar	645
Apr	916
May	339
Jun	88
Jul	13
Aug	1
Sep	0
Oct	0
Nov	0
Dec	0

Peak flowering in Apr, from 2,059 community-annotated observations worldwide. This is a global aggregate, not a forecast for your garden: the same species flowers on different dates in different hemispheres, and citizen-science records cluster near cities, at weekends, and in spring. Where a species has fewer than 30 annotated records we do not draw this chart at all.

Also published as 63 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.

Boothia californica (Benth.) Douglas ex Loudon
Platystemon aculeolatus Greene
Platystemon acutatus Greene
Platystemon anemonoides Greene
Platystemon antoninus Greene
Platystemon arizonicus Greene
Platystemon arvorum Greene
Platystemon australis Greene
Platystemon californicus var. californicus
Platystemon californicus var. ciliatus Dunkle
Platystemon californicus var. crinitus (Greene) Greene
Platystemon californicus var. horridulus (Greene) Jeps.
Platystemon californicus var. nutans Brandegee
Platystemon californicus var. ornithopus (Greene) Munz
Platystemon capsularis Greene
Platystemon cernuus Greene
Platystemon commixtus Greene
Platystemon communis Greene
Platystemon confinis Greene
Platystemon contortus Greene
Platystemon crenatus Greene
Platystemon crinitus Greene
Platystemon elegans Greene
Platystemon emarginatus Greene

and 39 more.

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.

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