Asclepias cordifolia |
Asclepias longifolia |
|
---|---|---|
heart-leaf milkweed, purple milkweed |
Florida milkweed, long-leaf milkweed |
|
Habit | Herbs. | Herbs. |
Stems | 1–20, ascending to spreading, unbranched, 25–100 cm, glabrous, glaucous, rhizomes absent. |
1–few, spreading to decumbent, unbranched, 25–70 cm, puberulent with curved trichomes, not glaucous, rhizomes absent. |
Leaves | opposite, sessile, stipular colleters absent; blade ovate to lanceolate, 3.5–11 × 1.8–8 cm, chartaceous, base cordate, clasping, margins entire, apex acute, mucronate, venation brochidodromous to eucamptodromous, surfaces glabrous, glaucous, margins minutely ciliate, laminar colleters absent. |
opposite or alternate, sessile or petiolate, with 1 or 2 stipular colleters on each side of petiole, also in axil; petiole 0–2 mm, puberulent with curved trichomes; blade linear to linear-lanceolate, 5–18 × 0.2–1 cm, chartaceous, base cuneate, margins entire, apex acute to attenuate, sometimes mucronate, venation brochidodromous, surfaces scabridulous to puberulent with curved trichomes, especially on veins, margins ciliate, laminar colleters absent. |
Inflorescences | terminal, branched, sometimes also extra-axillary at upper nodes, pedunculate, 5–20-flowered; peduncle 0.3–6.5 cm, apically sparsely pilose to glabrate, with few bracts. |
terminal and extra-axillary at upper nodes, sessile or pedunculate, 13–28(–36)-flowered; peduncle 0–6 cm, puberulent with curved trichomes, with 1 caducous bract at the base of each pedicel. |
Pedicels | 16–37 mm, sparsely pilose. |
9–16 mm, puberulent with curved trichomes. |
Flowers | erect to pendent; calyx lobes elliptic to lanceolate, 3–5 mm, apex acute, pilose; corolla red-violet, lobes reflexed with spreading tips, oval, 6–7 mm, apex acute, glabrous; gynostegial column 1–1.5 mm; fused anthers brown, cylindric, 1.5–2 mm, wings right-triangular, open at tip, apical appendages deltoid; corona segments white, tinged pink to red-violet at base, sessile, tubular, 2–3 mm, exceeded by style apex, base saccate, apex truncate, oblique, glabrous, internal appendage absent; style apex shallowly depressed, pink to red-violet. |
erect to spreading; calyx lobes narrowly lanceolate, 1.5–2 mm, apex acute, puberulent with curved trichomes; corolla white to greenish cream, purple at lobe tips, lobes reflexed, oblong, 3–5 mm, apex obtuse, glabrous; gynostegial column 0.2–0.5 mm; fused anthers green or brown, cylindric, 1–1.5 mm, wings triangular to trapezoidal, widest at middle, slightly open at tip, apical appendages ovate; corona segments pinkish lavender to red-violet, often with white apex, often a darker red-violet stripe or at base, sessile, laminar, strongly dorsally compressed, margins incurved, appressed to column, curved to subsaccate, 2–2.5 mm, exceeding point of anther wings, greatly exceeded by style apex, apex obtuse to truncate, glabrous, internal appendage absent or obscure, glabrous; style apex shallowly depressed, greenish cream to green. |
Seeds | ovate, 8–9 × 5–7 mm, margin not winged, faces reticulate-rugulose; coma 3–3.5 cm. |
ovate, 11–12 × 7–8 mm, margin winged, faces smooth; coma 4–5 cm. |
Follicles | erect on upcurved pedicels, lance-ovoid, 7.5–10.5 × 1.5–1.8 cm, apex long-acuminate, smooth, glabrous, glaucous. |
erect on upcurved pedicels, narrowly fusiform, 8–13.5 × 0.7–1.2 cm, apex attenuate, smooth, puberulent with curved trichomes. |
2n | = 22. |
|
Asclepias cordifolia |
Asclepias longifolia |
|
Phenology | Flowering Mar–Jul(–Aug); fruiting Jun–Sep. | Flowering (Jan–)Feb–Sep(–Oct); fruiting Apr–Aug. |
Habitat | Hillsides, canyons, ridge tops, streamsides, seeps, basalt, serpentine, gabbro, granite, shale, limestone, talus slopes, gravel, alluvium, oak woodlands, mixed evergreen, douglas-fir, pine, pine-oak, and riparian forests, chaparral, timberline meadows, grasslands. | Bogs, swamps, flats, ditches, depressions, pond edges, sandy, clay, and rocky soils, wet prairies, pine flatwoods, oak woodlands, savannas, pastures, often following fires. |
Elevation | 50–2200(–2800) m. [160–7200(–9200) ft.] | 0–100 m. [0–300 ft.] |
Distribution |
CA; NV; OR
|
AL; DE; FL; GA; LA; MS; NC; SC; VA
|
Discussion | Fresh leaves and stems of Asclepias cordifolia are often slightly or strongly colored bluish, grayish, or purplish. This is one of the few American species of Asclepias with cavitate corona segments that lack adaxial appendages. Such species were segregated along with diverse African species in Gomphocarpus R. Brown, a polyphyletic segregate (M. Fishbein et al. 2011; D. Chuba et al. 2017). Asclepias cordifolia is a distinctive species unlike any other within its range. It is phylogenetically and geographically isolated, although not highly derived morphologically. In Nevada, A. cordifolia is restricted to the Sierra Nevada, in Carson City, Douglas, and Washoe counties. Its range extends to northern California and southwestern Oregon. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Asclepias longifolia has sometimes been treated to include A. hirtella as conspecific, as discussed under that species. As circumscribed here, the distribution of A. longifolia extends along the Atlantic Coastal Plain south of Delaware to Florida and westward to the Mississppi River. Reports of A. longifolia from west of the Mississippi River in Louisiana and in Texas are assigned here to A. hirtella. Hence, the range of A. longifolia in Louisiana is extremely limited, and the conservation status of this species warrants assessment in that state (Livingston, Saint Helena, Saint Tammany, Tangipahoa, and Washington parishes). Reports of A. longifolia from Maryland and West Virginia have not been confirmed, and the species is considered extirpated from Delaware. Otherwise, it is rare at the northern extent of its range and considered to be of conservation concern in North Carolina and Virginia (Greensville and Prince George counties). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 14. | FNA vol. 14. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | Acerates cordifolia, Gomphocarpus cordifolius | Acerates floridana, A. longifolia, A. floridana |
Name authority | (Bentham) Jepson: Fl. W. Calif., 384. (1901) | Michaux: Fl. Bor.-Amer. 1: 116. (1803) |
Web links |