Onagraceae
Herbs, less commonly shrubs, occasionally trees or lianes. Lvs alternate, opposite or whorled, usually simple, usually exstipulate, sometimes with caducous stipules. Fls usually ⚥, actinomorphic or somewhat zygomorphic, solitary or in spikes, racemes or panicles. Axis adnate to ovary and mostly produced beyond it as the floral tube. Calyx lobes (2)-4-(5), valvate. Petals (0)-2-4-(5), free, convolute or imbricate, often clawed. Stamens usually 8 or 4, sometimes 1-2; anthers 2-locular; pollen grains connected by fine, viscid threads. Ovary usually inferior, rarely semi-superior, 2-4-(6)-celled. Ovules 1-numerous; placentation axile; style 1; stigmas 1-4. Fr. generally a capsule, sometimes a berry or dry and nut-like. Seeds nearly always numerous, non-endospermic; embryo straight.
Key
17 genera, c. 652 spp., mainly temperate and subtropical regions, some in tropical America.
In addition to the genera below, spp. of several other N. American genera, particularly Zauschneria Presl, are cultivated in N.Z. The floral tube is often referred to as a hypanthium or calyx tube.
