Vascular Plants of Williamson County

Malvaviscus arboreus var. drummondii [Malvaceae]
turk’s cap, drummond wax mallow

Malvaviscus arboreus Cav. var. drummondii (Torrey & A. Gray) Schery, turk’s cap, drummond wax mallow. Shrub, many–stemmed at base, in range to 140 cm tall; shoots with only cauline leaves, stellate–hairy, with 1—5 arms.

Stems

Stems cylindric, to 8 mm diameter, tough, green, with short unbranched and stellate hairs, the largest with 4—5 arms.

Leaves

Leaves helically alternate, palmately 3–lobed, long–petiolate, with stipules; stipules 2, attached to stem at base of petiole, spreading, linear, 7—9 × 1 mm, green, becoming reflexed before abscising; petiole cylindric, to 100 mm long, tough, stellate–hairy on upper side; blade broadly ovate to squarish with projecting, broadly triangular terminal lobe, 80—150 × < 65—155 mm, cordate at base, coarsely serrate–crenate on margins, acute to obtuse at lobe tips, palmately veined from base with 5, 7, or 9 principal veins with principal veins raised on upper surface but furrowed along edges and conspicuously raised on lower surface, stellate hairs along all veins, the arms 0.1—0.7(—1.1) mm long.

Inflorescence

Inflorescence solitary axillary flowers, bracteate, stellate–hairy; pedicel cylindric, ± 30 mm long, densely stellate–hairy, abscising at base, bracteoles 8—10 in whorl appearing like outer perianth whorl (epicalyx), in bud spreading later ascending to suberect, appressed to calyx, and persistent with spreading tips, narrowly spatulate–linear (2–lobed), 12—17 × 1.8—2.3 mm, slightly green flared at whitish base, 3–veined with midvein raised on lower surface, stellate–hairy and with longer unbranched hairs.

Flower

Flower bisexual, radial, 12—26 mm across; calyx 5–lobed, ca. 13 mm long, pale light green, stellate–hairy base–to–tip; tube narrowly bell–shaped, ca. 8 × 5 mm, 3–ribbed to each lobe; lobes triangular, 4.5—6 × 2.9—3.3 mm, with 3–principal veins, upper surface with stellate hairs above midpoint; petals 5, fused in a ring to expanded base of staminal column, twisted in bud, asymmetrically narrowly fan–shaped with deltate basal lobe or shoulder (same side on 5 petals), 25—35 × 15—20 mm, crimson, basal lobe to 5 mm long, sparsely short–ciliate on margins at tips of lobes, the hairs red; stamens ca. 25, monadelphous (all fused into long column surrounding style), 45—50 × 1 mm, orangish red aging purple–red, column twisted several times, sparsely papillate above midpoint, free filaments 1—2 mm long arising 5—6 mm from top; anthers dorsifixed, monothecal, ± 1 mm long, purple–red, longitudinally dehiscent; pollen pale purple; nectary on outside of staminal dome alternate with petal bases; pistil 1, ± 45 mm long; ovary superior, oblate, 2 mm across, cream–colored, 5–chambered, each chamber with 1 ovule; style 10–lobed, white to pale strawberry on lobes, the lobes stigmatic, 3.5—4 mm long, style with long, scattered purple–red hairs.

Fruit

Fruit berrylike schizocarp, of 5 fleshy mericarps, each mericarp 1–seeded, at maturity fruit oblate with depressed center and broadly topped, 8—9 × 11—13 mm, white maturing red–orange to scarlet, cover (exocarp) somewhat leathery, before drying smooth, glabrous; pulp somewhat dry, white; seapls acute and somewhat covering fruit.

Seed

Seed 3–sided ovoid, 5—6.2 × 3.5—4 mm, white to yellowish white.

A. C. Gibson