Plants perennial, rarely annual, submersed, floating-leaved, or emersed, glabrous to sparsely pubescent; rhizomes often present, occasionally terminated by tubers; stolons often present; corms absent; tubers white to brown, smooth. Roots septate. Leaves sessile or petiolate; petiole terete to triangular; blade with translucent markings absent, linear to obovate, base attenuate to hastate or sagittate, margins entire, apex round to acute. Inflorescences racemes, panicles, rarely umbels, of 1–17 whorls, erect, emersed or floating, rarely submersed; bracts coarse or delicate, apex obtuse to acute, smooth or papillose proximally to distally. Flowers unisexual, the proximal rarely with ring of sterile stamens; staminate flowers pedicellate, distal to pistillate flowers; pistillate flowers mostly pedicellate, rarely sessile; bracts subtending pedicels, lanceolate, shorter than pedicels, apex obtuse to acute; pedicels ascending to recurved; receptacle convex; sepals recurved in staminate flowers, recurved to erect in pistillate flowers, often sculptured, herbaceous to leathery; petals white, rarely with pink spot or tinge, entire; stamens 7–30; filaments linear to dilated, glabrous to pubescent; pistils to 1500 or more, spirally arranged, not radiating in starlike pattern, distinct; ovules 1; styles terminal. Fruits without longitudinal ribs, compressed, abaxially keeled or not, abaxial wings often present, lateral wing often present, 1, curved, glands present. x = 11.

Distribution

Mostly Western Hemisphere, Europe, Asia.

Discussion

Species ca. 30 (24 in the flora).

Key

1 Fruiting pedicels recurved or rarely spreading; pistillate sepals mostly erect and closely enclosing flower or fruiting head, occasionally spreading to recurved. > 2
1 Fruiting pedicels spreading to ascending or absent; pistillate sepals mostly spreading to recurved, not enclosing flower. > 9
2 Leaves, at least some, emersed. > 3
2 Leaves submersed, floating, rarely emersed, or plants stranded on shore. > 5
3 Fruiting heads 1.2–2.1 cm diam.; leaf blade hastate to sagittate Sagittaria montevidensis
3 Fruiting heads 0.7–1.2 cm diam.; leaf blade linear-ovate to lance-elliptic. > 4
4 Achenes abaxially keeled, mostly more than 2 mm; faces not tuberculate, often with glands; California. Sagittaria sanfordii
4 Achenes not abaxially keeled, mostly less than 2 mm, faces tuberculate, without glands; e of Rocky Mountains. Sagittaria platyphylla
5 Achene faces tuberculate; floating leaves with sagittate blades present at least on some plants of population. Sagittaria guayanensis
5 Achene faces not tuberculate; floating leaves absent or, if present, with unlobed or hastate blades. > 6
6 Fruiting pedicels 0.2–1.1 cm; phyllodia lenticular in cross section; tidal muds; mostly brackish waters. Sagittaria subulata
6 Fruiting pedicels 1.5–6.5 cm; phyllodia flattened in cross section; rarely tidal muds; mostly fresh waters. > 7
7 Leaves with blades and petioles usually present on some plants; some plants often stranded along shore, these usually with expanded leaf blades. Sagittaria filiformis
7 Leaves all phyllodia; plants almost always submersed, rarely stranded, these without expanded leaf blades. > 8
8 Phyllodia 50–250 cm; Florida springs. Sagittaria kurziana
8 Phyllodia 12–53 cm; streams and lakes, New Mexico. Sagittaria demersa
9 Filaments pubescent to tomentulose (except S. fasciculata). > 10
9 Filaments glabrous. > 17
10 Leaves all phyllodia, nearly terete; ne United States. Sagittaria teres
10 Leaves with blades and petioles or if phyllodia, then flattened to triangular in cross section; mostly widespread. > 11
11 Pistillate flowers sessile to subsessile. Sagittaria rigida
11 Pistillate flowers obviously pedicellate. > 12
12 Filaments cylindric. Sagittaria lancifolia
12 Filaments dilated. > 13
13 Rhizomes present, coarse; stolons and corms absent. > 14
13 Rhizomes absent or if present, then not coarse; corms and/or stolons present. > 15
14 Abaxial wing of fruit ± entire; plants widespread Sagittaria graminea
14 Abaxial wing of fruit scalloped or toothed; ne Alabama Sagittaria secundifolia
15 Filaments exceeding anthers in length. Sagittaria cristata
15 Filaments shorter than or equaling anthers in length. > 16
16 Blades of emersed leaves 0.5 cm or more wide; w Carolinas. Sagittaria fasciculata
16 Blades of emersed leaves, if present, 0.4(–0.5) cm or less wide; se coastal plain. Sagittaria isoetiformis
17 Emersed leaf blades linear to ovate. > 18
17 Emersed leaf blades cordate, sagittate, or hastate. > 20
18 Bracts papillose. Sagittaria papillosa
18 Bracts not papillose. > 19
19 Emersed plants with erect to ascending petioles; leaf blades lanceolate to ovate. Sagittaria ambigua
19 Emersed plants with recurved petioles; leaf blades linear to sagittate. Sagittaria cuneata
20 Bracts distinct or connate much less than ¼ total length. > 21
20 Bracts connate at least ¼ total length. > 23
21 Flowers in 2–4 whorls; achenes with facial glands. Sagittaria engelmanniana
21 Flowers in 5–12 whorls; achenes without facial glands. > 22
22 Petiole winged in cross section; achene beak strongly recurved. Sagittaria australis
22 Petiole ridged in cross section; achene beak ascending apically. Sagittaria brevirostra
23 Achene beak 1–2 mm, horizontal. Sagittaria latifolia
23 Achene beak 0.1–0.6 mm, erect or incurved. > 24
24 Emersed plants with recurved petioles and linear to sagittate blades; basal lobes equal to or shorter than remainder of blade; submersed leaves phyllodial, floating leaves cordate to sagittate Sagittaria cuneata
24 Emersed plants with ascending to erect petioles and sagittate blades; basal lobes longer than remainder of blade; submersed and floating leaves absent. Sagittaria longiloba
Facts about "Sagittaria"
AuthorRobert R. Haynes + and C. Barre Hellquist +
Common nameSagittaire +
EtymologyLatin sagitta, arrow +
IllustratorJohn Myers +
Referencebeal1982a +, bogin1955a +, rataj1972a + and wooten1973a +
SynonymLophotocarpus +
Taxon nameSagittaria +
Taxon parentAlismataceae +
Taxon rankgenus +
VolumeVolume 22 +