| | The Families of Angiosperms |
~ Euphorbiaceae
Habit and leaf form. Trees, or ‘arborescent’, or shrubs; non-laticiferous, without coloured juice. Plants green and photosynthesizing. Leaves persistent; alternate (usually), or opposite (rarely); distichous (commonly), or spiral; ‘herbaceous’, or leathery; petiolate; non-sheathing; simple. Lamina entire; pinnately veined; usually oblique at the base. Leaves stipulate. Stipules intrapetiolar; free of one another; caducous, or persistent. Lamina margins entire, or dentate. Leaf development not ‘graminaceous’.
General anatomy. Plants without laticifers.
Leaf anatomy. The leaf lamina dorsiventral. Lamina with secretory cavities. Secretory cavities containing oil.
Reproductive type, pollination. Unisexual flowers usually present, or absent. Plants hermaphrodite (rarely), or monoecious, or dioecious (?), or polygamomonoecious. Gynoecium of male flowers of Putranjiva vestigial. Floral nectaries present (sometimes with an intrastaminal disk), or absent. Nectar secretion when present, from the disk.
Inflorescence, floral, fruit and seed morphology. Flowers solitary, or aggregated in ‘inflorescences’. Inflorescences axillary, or in cauliforous clusters or pedicellate cymes. Flowers regular. Free hypanthium absent.
Perianth sepaline; imbricate, (3–)4, or 5(–6); free. Calyx (3–)4, or 5(–6); polysepalous.
Androecium 2–3 (Putranjiva), or 4–50 (Drypetes). Androecial members free of the perianth; free of one another. Androecium exclusively of fertile stamens (?). Stamens 2–50; filantherous. Anthers sub- dorsifixed to basifixed; dehiscing via longitudinal slits; introrse.
Gynoecium in female-fertile flowers, 1–3 carpelled, or 6 carpelled; normally syncarpous; of one carpel (rarely), or synovarious (usually); superior. Ovary (1–)2–3 locular, or 6 locular. Gynoecium stylate. Styles (1–)2–3, or 6; apical; much shorter than the ovary. Stigmas (1–)2–3, or 6; peltate, reniform, disc-shaped, bilobed or petaloid. Ovules in the single cavity when unilocular, 2; 2 per locule; pendulous; pseudocrassinucellate.
Fruit fleshy. The fruiting carpel indehiscent; drupaceous. Fruit indehiscent; a drupe (hairy, with simple or stellate hairs); 1–6 seeded (with one maturing per locule). Seeds endospermic. Cotyledons 2 (large,flat,fleshy). Embryo straight.
Physiology, phytochemistry. Mustard-oils present.
Geography, cytology. Worldwide tropical and subtropical.
Taxonomy. Subclass Dicotyledonae; Crassinucelli. Dahlgren’s Superorder Malviflorae; Euphorbiales. Cronquist’s Subclass Rosidae; Euphorbiales. APG III core angiosperms; core eudicot; Superorder Rosanae; fabid. APG IV Order Malpighiales.
Species about 220. Genera 2; Drypetes, Putranjiva.
General remarks. An inadequate draft description, cf. the poor offering of Christenhusz et al. (2017), and the Humbert (Fl. of Madagascar, 1958) treatment of Drypetes.
Economic uses, etc. Drypetes species provide edible fruits; Putranjiva roxburghii is widely cultivated as an ornamental, the seeds yield essential oil, and the bark is used medicinally.
Illustrations. • Drypetes sp. (inc. Hemicyclia), Sibangea arborescens and Putranjiva roxburghii, with Petalostigma (Picrodendraceae): Nat. Pflanzenfam. 3 (1896). • Drypetes capuronii, D. grandiflora, D. stipulacea: Humbert, Fl. Madagascar and Comores 1 (1958). • Drypetes coriifolia, D. ambigua, D oppositifolia: Humbert, Fl. Madagascar & Comores 1 (1958). • Drypetes madagascariensis: Humbert, Fl. Madagascar and Comores 1 (1958). • Putranjiva roxburghii: Brandis, Ill. Forest Flora of N.W. and Central India (1874).
We advise against extracting comparative information from the descriptions. This is much more easily achieved using the DELTA data files or the interactive key, which allows access to the character list, illustrations, full and partial descriptions, diagnostic descriptions, differences and similarities between taxa, lists of taxa exhibiting or lacking specified attributes, distributions of character states within any set of taxa, geographical distribution, genera included in each family, and classifications (Dahlgren; Dahlgren, Clifford, and Yeo; Cronquist; APG). See also Guidelines for using data taken from Web publications.
Cite this publication as: ‘Watson, L., and Dallwitz, M.J. 1992 onwards. The families of flowering plants: descriptions, illustrations, identification, and information retrieval. Version: 3rd September 2025. delta-intkey.com’.
