Tragia brevispica Engelm. & A. Gray, short–spike noseburn. Perennial vine, twining, taprooted, not rosetted, 1—several–stemmed at base, ascending or trailing and climbing by twining on taller herbs with many coils of internodes; monoecious; shoots with only cauline leaves, leaves widely spaced on tough, slender stems, short–hairy and with some longer, stiff, stinging hairs, mildly stinging when handled; latex absent; taproot to 4 mm diameter.
Stems ridged, to 1.5 mm diameter, with 3 ridges descending from each leaf at node connected by ledge (stipule bases), internodes > leaves, 30—70 mm long, tough and mostly < 1 mm diameter, short–hirsute with straight hairs and puberulent.
Leaves helically alternate, simple, petiolate with pulvinus, with stipules; stipules 2, attached broadly at node, triangular–ovate, 2.5—3(—5) × 1—1.5(—2) mm, green, short–ciliate on margins, with a long stinging hair at tip, with to 5 veins at base; petiole pulvinus 1 mm long, axis above pulvinus strongly ridged, 3.5—15 mm long, often curved or somewhat twisted, short–hairy and puberulent with longer stinging hairs on upper side; blade triangular to arrow–shaped, 15—28 × 15—18 mm, subcordate to cordate at base, serrate on margins, broadly acute (obtuse) at tip, at base palmate with 3 or 5(7) veins above pinnately veined with principal veins somewhat raised on upper surface and raised on lower surface, having a conspicuous vein network, hirsute with some longer stinging hairs, the stinging hairs concentrated on basal lobes and close to blade margins.
Inflorescence racemelike, 1 per node opposite petiole (not axillary), of 1(—2) pistillate flower on lower portion and several staminate flowers on upper portion, bracteate, pubescent; peduncle mostly widely spreading, ridged, to 10 mm long but shorter at anthesis of the first flower, puberulent with other short hairs; bractlet subtending pedicel of pistillate flower at first fork = 2 stipules but 1 often early–abscised, appressed, ovate symmetric or slightly asymmetric, ca. 1.5 × 1 mm, green, short–ciliate and somewhat jagged on margins; bractlet subtending pedicel of each staminate flower ovate, the lowest one stipulelike but cupped, ca. 1 mm long decreasing upward; pedicel of pistillate flower strongly ridged, to 3 mm long, axis below staminate flowers more slender than pedicel of pistillate flower; pedicel of staminate flower short— < 1 mm long, short–hairy.
Staminate flower radial, ca. 0.7 mm across; perianth (calyx) deeply (3—)4–lobed, fused only at base; lobes obovate, ca. 0.7 mm long, green, minute–hairy on outer (lower) surface; stamens (3—)4, opposite calyx lobes, scarcely fused at base; filaments ca. 0.2 mm long, green, glabrous; anthers dorsifixed, dithecal, 0.35—0.4 mm long, yellow–green, longitudinally dehiscent; pollen white; pistil absent.
Pistillate flower radial, 3—3.5 mm across; perianth (calyx and corolla) 6–lobed, green; tube widely spreading, 0.3—0.4 mm long; lobes in 2 whorls, at anthesis ascending, ovate, ca. 2 mm long, minutely–ciliate on margins and acute at tip, outer lobes 1.3—1.4 mm wide, inner lobes 0.7—0.8 mm long; stamens absent; pistil 1; ovary superior, strongly 3–lobed, ca. 1 mm long, often purple, with spheroid lobes concealed by stiff, white, stinging hairs ca. 1 mm long, 3–chambered, each chamber with 1 ovule attached to center; style 1 deeply 3–branched, in range fused ca. 0.25 mm at base, about 1.2 mm long, the branches green with curved stigmatic tips aging purple, minute–strigose on branches and papillate on stigmas.
Fruit schizocarp, of 3 dry, 1–seeded mericarps, before separating ca. 7 mm across, mericarps spheric, 3.2—3.6 mm, hard and thick–walled, aging light brown with many stinging hairs.
Seed lacking caruncle, spheric, in range ± 2.5 mm, mottled black and brown, with linear hilum ca. 1 mm long on inner side.
A. C. Gibson