Vines, twining, polygamodioecious. Branchlets terete. Leaves deciduous [persistent], alternate; stipules present; petiole present; blade margins denticulate; venation pinnate. Inflorescences terminal or axillary, panicles or cymes [racemes]. Flowers bisexual and unisexual, radially symmetric; perianth and androecium hypogynous; hypanthium absent; sepals 5, distinct; petals 5, white or greenish white; nectary intrastaminal, fleshy. Bisexual flowers: stamens 5, free from and inserted under nectary; staminodes 0; pistil 3-carpellate; ovary superior, 3-locular; placentation axile; style 1; stigmas 3; ovules 2 per locule. Staminate flowers: stamens 5; free from and inserted under nectary; staminodes 0; pistillode present. Pistillate flowers: staminodes 5, alternate with petals, undivided, not gland-tipped, minute; pistil 3-carpellate; ovary superior, 3-locular, placentation axile; style 1; stigmas 3; ovules 2 per locule. Fruits capsules, 3-locular, globose or subglobose, 3-lobed distally, apex not beaked. Seeds [1–]2 per locule, ellipsoid, not winged; aril red, completely surrounding seed. x = 23.

Distribution

North America, e Asia, primarily tropics and subtropics, some temperate regions.

Discussion

Species ca. 30 (2 in the flora).

Selected References

Hou, D. 1955. A revision of the genus Celastrus. Ann. Missouri Bot. Gard. 42: 215–302.

Leicht-Young, S. A. et al. 2007. Distinguishing native (Celastrus scandens L.) and invasive (C. orbiculatus Thunb.) bittersweet species using morphological characteristics. J. Torrey Bot. Soc. 134: 441–450.

Pooler, M. R., R. L. Dix, and J. Feely. 2002. Interspecific hybridizations between the native bittersweet, Celastrus scandens, and the introduced invasive species, C. orbiculatus. SouthE. Naturalist 1: 69–76.

Lower Taxa

Celastrus orbiculatus, Celastrus scandens

Key

1	Inflorescences terminal, panicles; capsules orange; pollen yellow; leaf blades usually oblong, aestivation involute.	Celastrus scandens
1	Inflorescences axillary, cymes; capsules yellow; pollen white; leaf blades suborbiculate to broadly oblong-obovate or ovate-orbiculate, aestivation conduplicate.	Celastrus orbiculatus