12. Malpighiaceae Jussieu
Malpighia Family Malpighia Family
William R. Anderson† 
Herbs, subshrubs, shrubs, vines (twining, woody to herbaceous), or trees, perennial, evergreen or deciduous, synoecious [dioecious or functionally dioecious]; hairs unicellular, usually 2-armed and medifixed or submedifixed [basifixed or stellate]. Leaves opposite [whorled, subopposite, or alternate], simple; stipules present [absent]; petiole present [absent]; blade margins usually entire [lobed], sometimes pseudodentate [ciliate at location of marginal glands or with stout bristlelike hairs], often bearing multicellular glands on margin or abaxial [adaxial] surface; venation pinnate. Inflorescences terminal or axillary, racemes, panicles, umbels, corymbs, or thyrses, or flowers solitary. Flowers bisexual [rarely unisexual], radially or bilaterally symmetric, mostly all chasmogamous, sometimes both chasmogamous and cleistogamous; perianth and androecium hypogynous [perigynous]; hypanthium absent [present]; sepals 5, distinct or connate basally, usually glandular, sometimes eglandular; petals (in chasmogamous flowers) 5, posterior (flag) petal often different from lateral 4, distinct, mostly clawed; nectary absent; stamens (in chasmogamous flowers) (2–5)[6–]10[–20], distinct or connate proximally, free; anthers dehiscing by longitudinal slits [apical or subapical pores or very short slits]; pistil 1, (2–)3-carpellate, carpels nearly distinct to completely connate in ovary [connate throughout], ovary superior, (2–)3-locular, placentation apical; ovule 1 per locule, anatropous; styles (in chasmogamous flowers) (1–)3 (usually as many as carpels but sometimes fewer by reduction [or connation]), distinct [partially to completely connate]; stigmas 1–3 (1 per style). Fruits drupes or schizocarps splitting into mericarps, mericarps nutlets, thin-walled cocci, or bearing wings [or vascularized setae] [berries or dry and indehiscent]. Seeds 1 per locule or mericarp.
Genera ca. 75, species ca. 1300 (8 genera, 9 species in the flora): nearly worldwide; tropics and subtropics.
Malpighiaceae are far more numerous and diverse in the New World than in the Old World. Many are grown as ornamentals in warm areas of the world; they are intolerant of cold. Malpighia emarginata de Candolle produces a fruit that is rich in vitamin C, which has been exploited commercially as acerola. One of the most famous hallucinogens in the world, ayahuasca or caapi, is extracted from Banisteriopsis caapi (Grisebach) C. V. Morton, a vine native to South America but cultivated widely.
In Malpighiaceae, the ancestral inflorescence appears to be a raceme of cincinni, but in most genera the cincinni have been reduced to 1-flowered units. The pedicel is usually borne on a peduncle, the juncture marked by two bracteoles (W. R. Anderson 1981). This morphology technically makes many inflorescences in the family cymose (cymes, dichasia, or thyrses). For simplicity, however, inflorescence types are described here based on their gross morphological appearance, treating reduced cincinni as if they were single flowers.
Most New World taxa bear two (sometimes one) large multicellular glands abaxially on all five sepals or on three or four lateral sepals. Many Old World taxa and some New World taxa (including one in the flora) have the calyx glands much reduced in number and size or absent. Calyx glands always are absent from cleistogamous flowers.
SELECTED REFERENCES Anderson, W. R. 2004. Malpighiaceae. In: N. P. Smith et al., eds. 2004. Flowering Plants of the Neotropics. Princeton. Pp. 229–232. Anderson, W. R. 2013. Origins of Mexican Malpighiaceae. Acta Bot. Mex. 104: 107–156. Davis, C. C. and W. R. Anderson. 2010. A complete generic phylogeny of Malpighiaceae inferred from nucleotide sequence data and morphology. Amer. J. Bot. 97: 2031–2048. Niedenzu, F. 1928. Malpighiaceae. In: H. G. A. Engler, ed. 1900–1953. Das Pflanzenreich.... 107 vols. Berlin. Vols. 91, 93, 94[IV,141], pp. 1–870.