Odontostephana carolinensis (maroon Carolina milkvine)

Plate 1 figs. a–h · 8 separate observations

Odontostephana carolinensis, photographed by Brian Finzel — fig. a Brian Finzel, CC BY-SA 4.0 / 2022-05-14 / obs. 197701138

Odontostephana carolinensis, photographed by Bill Sheehan — fig. b Bill Sheehan, CC BY-SA 4.0 / obs. 197033852

Odontostephana carolinensis, photographed by Eric Knight — fig. c Eric Knight, CC BY 4.0 / obs. 191929016

Odontostephana carolinensis, photographed by John Kees — fig. d John Kees, CC0 1.0 / obs. 159704108

Odontostephana carolinensis, photographed by kcthetc1 — fig. e kcthetc1, CC0 1.0 / obs. 142661042

Odontostephana carolinensis, photographed by Alan Weakley — fig. h Alan Weakley, CC0 1.0 / obs. 73005090

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 12 botanical countries

Native distribution of Odontostephana carolinensis, 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
Alabama	ALA	NORTHERN AMERICA
Delaware	DEL
District of Columbia	WDC
Georgia	GEO
Kentucky	KTY
Louisiana	LOU
Maryland	MRY
Mississippi	MSI
North Carolina	NCA
South Carolina	SCA
Tennessee	TEN
Virginia	VRG

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 129 in flower of 143 examined

91%

99%

83%

57%

Proportion of examined Odontostephana carolinensis in flower, by month
Month	In flower	Examined	Share	95% interval
Jan	0	0	too few examined
Feb	0	0	too few examined
Mar	0	1	too few examined
Apr	21	23	91%	73% to 98%
May	77	78	99%	93% to 100%
Jun	25	30	83%	66% to 93%
Jul	4	7	57%	25% to 84%
Aug	2	4	too few examined
Sep	0	0	too few examined
Oct	0	0	too few examined
Nov	0	0	too few examined
Dec	0	0	too few examined

Peak flowering in May. Each bar is the share of Odontostephana carolinensis 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. 129 of 143 examined observations were in flower, every one of them research grade. The whisker on each bar is a 95% Wilson interval. 8 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.

Also published as 13 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.

Asclepias acanthocarpus J.F.Gmel. ex Decne.
Cynanchum carolinense Jacq.
Cynanchum hirsutum (Michx.) Pers.
Cynanchum hirtum L.
Cynanchum macrophyllum Pers.
Echites truncatus (Jacq.) Lam.
Gonolobus carolinensis (Jacq.) Schult.
Gonolobus hirsutus Michx.
Gonolobus hirtus (L.) Schult.
Matelea carolinensis (Jacq.) Woodson
Vincetoxicum acanthocarpos Walter
Vincetoxicum carolinense (Jacq.) Britton
Vincetoxicum hirsutum (Michx.) Britton

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.
USDA PLANTS Database. common name, checklist symbol MACA9. public domain. 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.