Biancaea decapetala (shoofly)

Plate 1 figs. a–h · 8 separate observations

Biancaea decapetala, photographed by Jacy Chen — fig. a Jacy Chen, CC BY 4.0 / 2022-05-04 / obs. 202646284

Biancaea decapetala, photographed by Shaun Swanepoel — fig. b Shaun Swanepoel, CC BY 4.0 / obs. 183245741

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 27 botanical countries

Native distribution of Biancaea decapetala, 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. Regions too small to draw at this scale are marked with a dot.

Region	TDWG code	Continent
Assam	ASS	ASIA-TROPICAL
Bangladesh	BAN
East Himalaya	EHM
India	IND
Jawa	JAW
Laos	LAO
Lesser Sunda Is.	LSI
Malaya	MLY
Myanmar	MYA
Nepal	NEP
Pakistan	PAK
Philippines	PHI
Sri Lanka	SRL
Sulawesi	SUL
Sumatera	SUM
Thailand	THA
Vietnam	VIE
West Himalaya	WHM
China North-Central	CHN	ASIA-TEMPERATE
China South-Central	CHC
China Southeast	CHS
Hainan	CHH
Japan	JAP
Korea	KOR
Nansei-shoto	NNS
Taiwan	TAI
Yemen	YEM

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 257 in flower of 311 examined

44%

38%

57%

83%

100%

86%

93%

94%

95%

63%

54%

Proportion of examined Biancaea decapetala in flower, by month
Month	In flower	Examined	Share	95% interval
Jan	4	9	44%	19% to 73%
Feb	5	13	38%	18% to 64%
Mar	4	7	57%	25% to 84%
Apr	5	6	83%	44% to 97%
May	10	10	100%	72% to 100%
Jun	51	59	86%	75% to 93%
Jul	28	30	93%	79% to 98%
Aug	33	35	94%	81% to 98%
Sep	105	111	95%	89% to 98%
Oct	5	8	63%	31% to 86%
Nov	7	13	54%	29% to 77%
Dec	0	10	0%	0% to 28%

Peak flowering in May. Each bar is the share of Biancaea decapetala 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. 257 of 311 examined observations were in flower, every one of them research grade. The whisker on each bar is a 95% Wilson interval. 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 878 observations

Condition	5th percentile	Median	95th percentile
Coldest month, mean daily low	1.0 °C	9.0 °C	19.4 °C
Warmest month, mean daily high	23.5 °C	27.2 °C	31.0 °C
Annual rainfall	671 mm	945 mm	2,445 mm
Rainfall in the driest quarter	34 mm	62 mm	292 mm

It is found where winters are cool but frost is light or absent. This is not care advice and it is not a forecast. It is a measurement: we sampled the climate at every one of the 878 research-grade observations of Biancaea decapetala 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 22 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.

Biancaea ferox (Hassk.) Tod.
Biancaea scandens Tod.
Biancaea sepiaria (Roxb.) Tod.
Caesalpinia benguetensis Elmer
Caesalpinia decapetala (Roth) Alston
Caesalpinia decapetala var. decapetala
Caesalpinia decapetala var. japonica (Siebold & Zucc.) Isely
Caesalpinia decapetala var. japonica (Siebold & Zucc.) H.Ohashi
Caesalpinia decapetala var. pubescens (Tang & F.T.Wang ex C.W.Chang) X.Y.Zhu
Caesalpinia ferox Hassk.
Caesalpinia horrida A.Rich.
Caesalpinia japonica Siebold & Zucc.
Caesalpinia sepiaria Roxb.
Caesalpinia sepiaria var. auricoma Trimen
Caesalpinia sepiaria var. japonica (Siebold & Zucc.) Hand.-Mazz.
Caesalpinia sepiaria var. japonica (Siebold & Zucc.) Gagnep.
Caesalpinia sepiaria var. japonica (Siebold & Zucc.) Makino
Caesalpinia sepiaria var. pubescens Tang & F.T.Wang ex C.W.Chang
Mezoneuron benguetense (Elmer) Elmer
Mezoneurum benguetense (Elmer) Elmer
Mezonevron benguetense (Elmer) Elmer
Reichardia decapetala Roth

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.