16. Triadica Loureiro, Fl. Cochinch. 2: 598, 610. 1790.
[Greek and Latin triadis, a group of three, alluding to 3-merous flowers] [Greek and Latin triadis, a group of three, alluding to 3-merous flowers]
Kenneth J. Wurdack
Trees, monoecious; hairs absent; latex white. Leaves deciduous, alternate, simple; stipules present, persistent; petiole present, glands present at apex; blade unlobed, margins entire, laminar glands abaxial, submarginal, occasionally absent on some leaves; venation pinnate. Inflorescences bisexual (pistillate flowers proximal, staminate distal) or staminate, terminal and subterminal (in axils of branch-tip leaves), racemelike thyrses; glands subtending each bract 2. Pedicels present. Staminate flowers: sepals 3, apparently imbricate, connate most of length; petals 0; nectary absent; stamens 2–3, distinct; pistillode absent. Pistillate flowers: sepals 3, distinct or connate basally; petals 0; nectary absent; pistil 3-carpellate; styles 3, connate 1/2–2/3 length, unbranched. Fruits capsules. Seeds ovoid with ventral face distinctly flattened or angled; outer seed coat fleshy; caruncle absent. x = 11.
Species 3 (1 in the flora): introduced; Asia.
Although classified historically in Sapium sect. Triadica, Triadica is distinct based on morphology and molecular phylogenetic evidence (K. Wurdack et al. 2005).
SELECTED REFERENCES DeWalt, S. J., E. Siemann, and W. E. Rogers. 2011. Geographic distribution of genetic variation among native and introduced populations of Chinese tallow tree, Triadica sebifera (Euphorbiaceae). Amer. J. Bot. 98: 1128–-1138. Esser, H.-J. 2002. A revision of Triadica Lour. (Euphorbiaceae). Harvard Pap. Bot. 7: 17–21.