Asclepias curassavica
Asclepias subulata
blood flower, bloodflower milkweed, hierba de la cucaracha, tropical milkweed, wild ipecacuanha
ajamete, candelilla, rush milkweed
1–several, erect, sparsely to moderately branched, 30–150 cm, minutely pilosulous in a line to glabrate, not glaucous, rhizomes absent.
3–100 (usually few–numerous), erect to ascending, branched, especially in lower half, 50–175 cm, sparsely pilosulous to glabrate, thickly glaucous, rhizomes absent.
persistent or gradually caducous from the base, opposite, petiolate, with 1 or 2 stipular colleters on each side of petiole on a ciliate interpetiolar ridge;
petiole 4–25 mm, puberulent with curved trichomes in a line to glabrate;
blade elliptic or oval to linear, 4–18 × 0.3–4.5 cm, membranous, base cuneate, margins entire, apex acute to acuminate to attenuate, venation eucamptodromous to faintly brochidodromous, surfaces sparsely puberulent with curved trichomes on veins abaxially, sparsely puberulent with curved trichomes on veins to glabrate adaxially, margins ciliate, laminar colleters absent.
ephemeral, often present on flowering stems, opposite (rarely whorled), sessile, with 0 or 1 stipular colleter on each side of leaf base;
blade filiform, 2–6 × 0.1 cm, succulent, base cuneate, margins entire, apex acute, mucronate, venation obscure, surfaces pilosulous, laminar colleters absent.
extra-axillary, pedunculate, 5–22-flowered;
peduncle 0.5–8 cm, puberulent with curved trichomes in a line, with 1 caducous bract at the base of each pedicel.
extra-axillary, pedunculate, 3–21-flowered;
peduncle 0.4–1.7 cm, sparsely pilose, glaucous, with 1 caducous bract at the base of each pedicel.
7–20 mm, puberulent with curved trichomes.
11–21 mm, pilose.
erect;
calyx lobes linear-lanceolate, 3–4 mm, apex acute, puberulent with curved trichomes;
corolla red, sometimes yellow in throat (to wholly orange or yellow in cultivars), lobes reflexed with spreading tips, elliptic to oval, 6–9 mm, apex acute, glabrous abaxially, minutely papillose at base adaxially;
gynostegial column 2–2.5 mm;
fused anthers yellowish green to tan, cylindric, 1.5–2 mm, wings narrowly right-triangular, closed, apical appendages deltoid;
corona segments yellow to orange, stipitate, tubular, dorsally somewhat flattened, 3.5–4 mm, exceeding style apex, apex obtuse to acute, glabrous, internal appendage falcate, exserted, arching over style apex, glabrous;
style apex shallowly depressed, yellow.
erect to spreading;
calyx lobes lanceolate, 4–4.5 mm, apex acute, pilose;
corolla green, sometimes tinged cream, yellow, or red, faintly striate, lobes reflexed, lanceolate, 7–12 mm, apex acute, glabrous;
gynostegial column 1–1.5 mm;
fused anthers brown, cylindric, 2–3 mm, wings right-triangular, distended at base, open at tip, apical appendages ovate;
corona segments cream, often tinged pink, yellow, or green, shiny, sessile, tubular, 7–9 mm, greatly exceeding style apex, base saccate, apex truncate, spreading, with proximal flaps, glabrous, internal appendage crested, apically falcate and sharply inflexed towards style apex, barely exserted, minutely papillose;
style apex shallowly depressed, cream to green.
ovate, 6–7 × 4–5 mm, margin winged, faces minutely rugulose to smooth;
coma 2.5–3 cm.
flat to somewhat naviculate, ovate, 6–8 × 4–5 mm, margin narrowly winged, faces papillose-rugulose, concave face with a low keel;
coma 1.5–3 cm.
erect on straight pedicels, fusiform, 6–10 × 0.5–1.2 cm, apex acuminate to attenuate, smooth, glabrous.
pendulous on spreading pedicels, fusiform, 6.5–13.5 × 1–1.8 cm, apex acuminate, smooth, sparsely pilosulous or puberulent with curved trichomes to glabrate, glaucous.
= 22.
= 22.
Asclepias curassavica
Asclepias subulata
Asclepias curassavica is the only non-native Asclepias species naturalized in the flora area. It is very commonly cultivated, originally for its strikingly colored flowers and their attraction of Lepidoptera and Hymenoptera. Recently, they have been valued also as a host plant for monarch butterflies. Cultivars with pure orange or pure yellow flowers are readily available. The species develops rapidly from seed and can be grown as an annual (in the horticultural sense) anywhere in the region. Though often described as an annual, like all species of Asclepias, it has a perennial habit. It may persist through mild winters at least as far north as Oklahoma but has only become established in frost-free areas of the southern United States.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Morphological and ecological distinctions between Asclepias subulata and its close relative, A. albicans, are discussed under the latter species. The range of A. subulata is more extensive than A. albicans and is almost exactly confluent with that of the Sonoran Desert, although it extends into the southeastern part of the Mohave Desert. In Nevada, it is restricted to Clark and Lincoln counties. The elongate, tubular, cream corona segments are remarkably similar to those of A. nyctaginifolia. These species were formerly considered close relatives (R. E. Woodson Jr. 1954), but they are highly dissimilar morphologically, other than the corona segments. They appear to be only distantly related (M. Fishbein et al. 2011, 2018), and the corona similarities represent a remarkable convergence. Both species are commonly visited by long-tongued tarantula hawk wasps (Pompilidae, Pepsinae), but it is not known whether they are important pollinators for these milkweeds.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
CA
LA Plants
WildflowerSearch
iNaturalist
USDA Plants Database
