in J. C. Frémont, Rep. Exped. Rocky Mts.,312. 1845
Common names: Spiny-caper
Etymology: Greek oxys, sharp, and stylos, pillar, alluding to style
Found in FNA Volume 7. Treatment on page 215. Mentioned on page 199, 200, 205.
Herbs, annual (unpleasantly scented). Stems unbranched, or sparsely branched laterally; glabrous or glabrate. Leaves: stipules 3–8-palmatifid, minute; petiole without pulvinus (slightly longer than leaflets); leaflets 3. Inflorescences axillary (from distal leaves), racemes (flat-topped); bracts present. Flowers actinomorphic; sepals persistent, distinct, equal (each often subtending a nectary); petals equal; stamens 6; filaments inserted on a spheroidal gynophore, glabrous; anthers (ellipsoid), coiling as pollen is released; gynophore sharply deflexed in fruit (stout, style spinelike in fruit). Fruits schizocarps (didymous, deflexed), indehiscent, obovoid. Seeds 2, reniform, not arillate. x = 10.
sw United States.