Sagittaria longiloba |
Sagittaria platyphylla |
|
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Gregg arrowhead, long lobed arrowhead, long-barb arrowhead, longlobe arrowhead |
delta arrowhead |
|
Habit | Herbs, perennial, to 100 cm; rhizomes absent; stolons present; corms present. | Herbs, perennial, to 150 cm; rhizomes absent; stolons present; corms present. |
Leaves | emersed; petiole 5-ridged, ascending to erect, 24.5–60 cm; blade sagittate, 11.5–26.5 × 0.8–15 cm, basal lobes longer than remainder of blade. |
submersed and emersed; submersed sessile, phyllodial, flattened, to 26 × 0.5 cm; emersed with petiole ± triangular, 21–70.5 cm, blade linear-ovate to ovate, 4.6–16.4 × 0.7–6.1 cm. |
Inflorescences | racemes, rarely panicles, of 5–17 whorls, emersed, 20–37 × 5–27 cm; peduncles 25–96 cm; bracts connate more than or equal to ¼ total length, lanceolate, 6.5–15 mm, delicate, not papillose; fruiting pedicels spreading, cylindric, 1.5–4.4 cm. |
racemes, of 3–9 whorls, emersed, 2.5–10 × 2–4.5 cm; peduncles 22–60 cm; bracts connate more than ¼ total length, lanceolate, 3–5.5 mm, delicate, not papillose; fruiting pedicels spreading to recurved, cylindric, 0.5–3 cm. |
Flowers | to 3 cm diam.; sepals recurved to spreading, not enclosing flower; filaments cylindric, shorter than anthers, glabrous; pistillate flowers pedicellate, without ring of sterile stamens. |
to 1.8 cm diam.; sepals spreading to recurved, not enclosing flower or fruiting head; filaments dilated, longer than anthers, pubescent; pistillate pedicellate, without ring of sterile stamens. |
Fruiting | heads 0.9–1.5 cm diam; achenes oblanceoloid, abaxially keeled, 1.2–2.5 × 0.8–1.6 mm, beaked; faces tuberculate, wings absent, glands 0–1; beak lateral, erect, 0.1–0.6 mm. |
heads 0.7–1.2 cm diam.; achenes oblanceoloid, not abaxially keeled, 1.2–2 × 0.8–1.2 mm, beaked; faces tuberculate, wings absent, glands absent; beak lateral, horizontal to erect, 0.3–0.6 mm. |
2n | = 22. |
|
Sagittaria longiloba |
Sagittaria platyphylla |
|
Phenology | Flowering summer–fall. | Flowering summer–fall. |
Habitat | Wet ditches, ephermeral pools, and margins of streams and lakes | Streams and lakes |
Elevation | 0–300 m (0–1000 ft) | 0–900 m (0–3000 ft) |
Distribution |
AZ; CA; KS; NE; OK; TX; Mexico; Central America (Nicaragua)
|
AL; AR; FL; GA; IL; KY; LA; MO; MS; OH; OK; PA; TN; TX; WV; Mexico (Nuevo León Mexico, sw Mexico); Central America (Panama)
|
Discussion | Sagittaria platyphylla has been accepted at the variety level, i.e., Sagittaria graminea var. platyphylla (C. Bogin 1955; J. W. Wooten 1973; E. O. Beal et al. 1982). After studying dozens of populations in the field from much of its range and hundreds of herbarium specimens, we have concluded that this taxon should be recognized at the specific level instead, a conclusion supported by cladistic analyses of morphologic characters (R. M. Kortright 1998) (Discussion copyrighted by Flora of North America; reprinted with permission.) |
|
Source | FNA vol. 22. | FNA vol. 22. |
Parent taxa | Alismataceae > Sagittaria | Alismataceae > Sagittaria |
Sibling taxa | ||
Synonyms | S. greggii | S. graminea var. platyphylla, S.. mohrii |
Name authority | Engelmann ex J. G. Smith: N. Amer. Sagittaria. 16, plate 11. (1894) | (Engelmann) J. G. Smith: N. Amer. Sagittaria. 29. (1894) |
Web links |