Kallstroemia parviflora J. B. S. Norton, warty caltrop. Annual, taprooted, many–stemmed at base, matlike with radiating shoots often forked but not rooting at nodes, prostrate and trailing, < 5 cm tall, mat to 150 cm across with principal shoots to 110 cm long; shoots ± 2–dimensional (plagiotropic), hirsute (to 2 mm long) with most hairs < 1 mm long.
Stems cylindric, to 5 mm in diameter, tough, green, principal axes zigzagged, commonly swollen at bases of internodes + nodes, internodes 20—50 mm long.
Leaves opposite decussate, even–1–pinnately compound, with one leaf larger at each node (anisophyllous, 1 less pair of leaflets), pairs of lateral leaflets in range (2—)3—5 and mostly angled forward, oblong in outline with subequal leaflets, petiolate, with stipules; stipules 2 (4 per node), fused to lower stem and petiole at swollen node, narrowly acuminate–triangular, 2.5—4 mm long, with straight hairs 0.5—1 mm long; petiole with pulvinus, to 7 mm long, pulvinus ca. 2 mm long, above pulvinus cylindric to shallowly channeled; rachis in range 4—32 mm long, extended beyond the uppermost pair of leaflets, ± strigose with upward–pointing hairs and some long hairs; petiolules pulvinuslike, to 0.5 mm long, pale green; blades of leaflets elliptic or obovate to narrowly ovate, (2—)5—22 × 2—10 mm, ± asymmetric and oblique at base, entire, acute to obtuse at tip, pinnately veined with midrib raised on lower surface, often 2–veined at base and midrib not centered, upper surface with long hairs along whitish midrib, lower surface paler and margins somewhat strigose.
Inflorescence flowers solitary (several–flowered cyme), axillary but only on 1 per node alternating side to side, the inflorescence and a new shoot axillary to the small leaf, lacking bracts; pedicel ascending, straight, 10 × 1 mm increasing to 25 mm long in fruit.
Flower bisexual, radial, 3.5 mm across if corolla cupped and ca. 10 mm across if petals spreading and dish–shaped; receptacle a low, broad disc; sepals (4—)5, ascending, subequal, narrowly lanceolate to narrowly triangular, 4.5—5 mm long not increasing in fruit, green with membranous margins, hirsute with coarse hairs to 2 mm long and some fine, shorter hairs, coarse hairs with bulbous bases (pustulate), calyx persistent in fruit; petals (4—)5, overlapping in bud, fan–shaped to obovate, 3.5—5 × 2.8—3.3 mm, yellow–orange, margin often scalloped (shallowly notched) at top, pinnately veined; nectaries (4—)5, opposite sepals and at bases of sterile staminoides (outer stamens), crescent–shaped to projecting, 0.2 × 0.2—0.4 mm, fleshy, green to orangish; stamens (4—)5 in inner whorl and 4—7 staminodes in outer whorl, staminodes free and appressed to ovary, fertile stamens attached to base of petals; filaments of fertile stamens gradually tapered base to tip, ca. 2.5 mm long, red–orange at base to yellow–orange (white at tip), of staminodes slender and 0.7—1 mm long; anthers versatile but oriented vertically, dithecal, elliptic, 1.4—1.8 mm long, apricot–orange often minutely orange–dotted, longitudinally dehiscent; pollen light orange; pistil 1, 3—4.5 mm long, subtended by low, broad disc; ovary superior, short barrel–shaped, low 10–lobed, 0.7 × 1.5 mm, green, densely short–hirsute with glabrous furrows, lobes = chambers, each chamber with 1 ovule attached to center; style ± columnar to narrowly conic, 2—2.5 × 1 mm, green, short–strigose; stigmas = 10, reflexed from top of and appressed to style, to 1 mm long, green, densely papillate.
Fruit schizocarp, breaking into 10 dry mericarps (nutlets), each mericarp 1–seeded, boney, straw–colored and low–warty (prickles absent), short–strigose on rounded outer face; immature fruit body broadly ovoid, 9—10 mm long, at chambers ca. 6 mm wide, low 10–ribbed, mericarps separating from central column with beak at top; mericarps D–shaped in outline and 3–sided, ± 3 × 2 mm, initially flat on 2 faces and rounded with low warts on back, the flat faces brown and when dry shallowly pitted to sculptured; central column ca. 3 × 1.5 mm, the beak narrowly conic rounded at tip, 4—6 × 3 mm, often reddish before drying, beak > central column, 10–grooved and short–strigose with upward–pointing hairs; sepals ± to top of mericarps.
A. C. Gibson