5. Celastraceae R. Brown
Staff-tree or Bittersweet Family Staff-tree or Bittersweet Family
Peter W. Ball
Geoffrey A. Levin
Herbs, shrubs, trees, or vines, annual or perennial, deciduous or evergreen, synoecious, dioecious, or polygamomonoecious. Leaves alternate, subopposite, opposite, whorled, or fascicled, simple; stipules absent or present; petiole present or absent; blade margins serrate, dentate, spiny, or entire; venation pinnate, palmate, or 1-veined, sometimes obscure. Inflorescences unisexual or bisexual, terminal or axillary, cymes, racemes, panicles, thyrses, or fascicles, or flowers solitary. Flowers bisexual or unisexual, radially symmetric or weakly asymmetric; perianth and androecium hypogynous or perigynous; hypanthium free, completely adnate to ovary, or absent; sepals (3–)4–5[–7], distinct or connate proximally; petals 0 or (3–)4–5[–7], distinct; nectary present, rudimentary, or absent; stamens 3–5[–10], distinct, free or adnate to nectary; anthers dehiscing by longitudinal slits; <staminodes 0 or [4–]5[–7]>; pistil 1, 1–5-carpellate, ovary superior <often embedded in nectary> to 1/2 inferior, 1–5-locular, placentation axile or parietal; ovules 1–2[–4] or 100–2000+ per locule, anatropous; styles 0, 1, or 3, connate proximally; stigmas 2–5. Fruits capsules, dehiscence loculicidal, drupes, or nutlike (small, hard-walled, indehiscent, 1-locular, and 1-seeded) [berries or samaras]. Seeds 1, 2, 40–70, or 100–2000+ per locule, <often winged or covered by brightly colored pulpy aril>.
Genera ca. 100, species ca. 1400 (12 genera, 34 species in the flora): North America, Mexico, West Indies, Central America, South America, Eurasia, Africa, Atlantic Islands, Indian Ocean Islands, Pacific Islands, Australia.
As treated here, Celastraceae include Hippocrateaceae Jussieu and Parnassiaceae Martinov. Both DNA sequence data and morphology place Hippocratea and its relatives nested within Celastraceae as subfam. Hippocrateoideae Lindley (M. P. Simmons et al. 2001; Simmons 2004, 2004b). Placement of Parnassiaceae (Lepuropetalon and Parnassia) is less certain. The group has long been associated with Saxifragaceae (such as by J. D. Hooker 1865b, A. Cronquist 1981), but broad-scale phylogenetic analyses utilizing DNA sequences have aligned Parnassiaceae with Celastraceae, either as a sister family or as a basal member of Celastraceae (M. W. Chase et al. 1993; Simmons et al. 2001b; Simmons 2004; Zhang L. B. and Simmons 2006). Including Parnassiaceae within Celastraceae follows APGIII (Angiosperm Phylogeny Group 2009).
Glossopetalon (sometimes under the illegitimate name Forsellesia Greene), included within Celastraceae in many local floras in North America, belongs in Crossosomataceae (R. F. Thorne and R. Scogin 1978; V. Sosa and M. W. Chase 2003); see Flora of North America North of Mexico, volume 9, page 9.
Some members of Celastraceae are of economic importance. Species of Celastrus, Euonymus, Maytenus, and Paxistima are grown as ornamentals, and Euonymus, Hippocratea, and Maytenus have medicinal uses.
SELECTED REFERENCE Brizicky, G. K. 1964. The genera of Celastraceae in the southeastern United States. J. Arnold Arbor. 45: 206–234.