Shrubs or herbs, monoecious. Exudate (from cut stems) present, white. Unarmed. Indumentum present, hairs simple, dendritic or stellate. Stipules free, simple, unlobed, entire, not spine-like*, not leaf-like*, without glands. Leaves distributed evenly along stem, alternate, simple, unlobed or with small basal lobes, base symmetrical, margin toothed or entire, teeth glandular or margin glandular-hyaline, blade not pellucid-punctate, with a few glands on lower surface near base; venation pinnate; domatia absent*; stipel-like structures absent. Petiole present or absent (leaves sessile), without swellings or bends at base or apex*, without glands. Inflorescence with axis, axillary, leaf-opposed (often) or terminal; bracts 2-glandular, not leaf-like, green; floral buds initially covered by their large bracts, later erect. Male flowers: pedicels absent or present, not articulated*; sepals 3; free or almost so, greenish; petals 0; disc 0; stamens 3, free; anther without conspicuous modification, thecae extrorse in bud; pistillode absent. Female flowers: pedicels absent or present, not articulated*; sepals 3, free, with or without minute glands at base, greenish; petals 0; disc 0; ovary locules 3, ovules per locule 1; styles 3, free to completely fused (stigmas free), entire, styles or stigmas not flat*, surface smooth*; staminodes absent. Fruit dehiscent, horned, rarely smooth, hairy or glabrous, greenish to brown; seed with caruncle, with no other covering or membranous layer; embryo flat, not minute, cotyledons leaf-like.
An asterisk * indicates a state has been assumed but not yet confirmed.
World Checklist: 15 spp.
With thanks to Hans-Joachim Esser (Botanische Staatssammlung München) for help with this genus.