Clematis texensis Buckl., scarlet clematis, red leatherflower. Perennial climber woody at base, dieback and deciduous, twining and with tendrils, clammering over neighboring shrubs; shoots with only cauline, pinnately compound leaves, leaves widely spaced and variously oriented, “leathery,” appearing glabrous but initially with ephemeral soft hairs; tendril = terminal leaflet or leaflets modified as axis.
Stems somewhat 6–sided and inconspicuously 12–ridged, on new growth to 3.5 mm diameter but widely flaring where leaves fused across node, internodes to 190 mm long, tough, green often tinged purple–red on upper side, where flared below leaf having a pair of depressions.
Leaves opposite decussate, odd–1–pinnately compound with (3—)4(—5) pairs of lateral leaflets and the terminal leaflet (axis) modified as a tendril or sometimes 1—2 adjacent leaflets also modified as tendrils, petiolate, without stipules; petiole channeled, to 55 mm long, flared at base, glaucous in channel; rachis with a pair of ridges on upper side bearing leaflet, tough, appearing segmented with pairs of leaflets widely spaced along rachis; petiolule somewhat enlarged at base but not a pulvinus, pulvinuslike at top of petiolule next to blade, to 40 mm long, swelling often sparsely hairy; blades of leaflets broadly ovate or somewhat kidney–shaded to inversely heart–shaped or mitten–shaped with 1—2 basal lobes, < 25—55 × < 35—65 mm, occasionally having a petiolulate lower lobe (secondary leaflet), cordate to subtruncate (rounded) at base, entire or with inconspicuous deltate teeth on margins, mostly rounded with folded–acuminate point at tip, pinnately veined with 3 veined at base but forming an elaborate vein network and principal veins raised on lower surface, upper surface ± glaucous, lower surface low–cobblestonelike (verrucose) with patches minutely textured, glabrous or with several hairs.
Inflorescence cyme, terminal on axillary shoot, 1—several–flowered (7), 2 cymes per node but 1 cyme developing earlier, bracteate; stem axis ascending, cylindric, to 50 × 3 mm, tough, often purple–red on exposed side; bracts subtending peduncle (pedicel) 2 and opposite, leaflike, petiolate, and fused across node, petiole deeply channeled and to 10 mm long, blade broadly ovate, to 60 × 40 mm, truncate at base, entire and unlobed; peduncle cylindric enlarged at base, to 170 × 1.5 mm, tough, purple–red on exposed side, glaucous at base, at flowering peduncle and pedicel strongly curved downward approaching flower; bractlet subtending flower cupped–ovate to broadly ovate with acuminate tip, to 4.5 × 2.5—3.5 mm, light green, appressed to 1/2 of very young bud, abscising very early by bud growth.
Flower bisexual, radial, before anthesis nodding, ca. 22 × 17 mm, bud slightly depressed subtruncate at base, with 8 broad, low ribs; receptacle with pistils (torus) hemispheric, 1.5 × 3 mm, green, with short hairs between ovaries; nectaries absent; sepals 4, calyx appearing urn–shaped, free but adhering by short–tomentose hairs on adjacent inner margins, gaping at anthesis forming recurved tip later separating downward, ± triangular, ca. 19 × 9.5 mm but opposite pairs of slightly different lengths, scarlet, thick, of spongy tissue, outer surface glabrous, inner surface white–tomentose and densely so approaching tip, abscising in developing fruit; petals absent; stamens 30—40 in 3 series, helically alternate, free, included, lacking staminodes; filaments decurrent, narrowly curved, ca. 8 × 2—3 mm, white at base and greenish, villous; anthers basifixed, dithecal, ± 7 mm long including fingerlike extensions of connectives 0.5—0.7 mm long, whitish with greenish connective, having short hairs along connective, longitudinally dehiscent; pollen white; pistils ca. 30, helically alternate on elevated torus, included, 8.5—11 mm long, densely silky–hairy; ovaries superior, 2.5 × 0.4 mm, 1–chambered with 1 ovule; style to 9 mm long, indistinct from ovary, whitish, strigose aging short–strigose.
Fruits achenes, to 30 in headlike cluster terminal on long pedicel, each achene with a long, feathery beak (persistent style); achene indehiscent, 1–seeded, ± ovate in outline compressed side–to–side and depressed seed chamber (faces) but biconvex over seed, 7.5—10 × 5—6 × 2 mm, light brown to brown, ± strigose on faces with strongly appressed fine hairs; beak looped to whiplike or curved to twisted (never straight), 27—34 mm long, purplish brown to brown, densely pilose with ascending to spreading, golden, straight hairs 2—3+ mm long.
A. C. Gibson