Sagittaria demersa

J. G. Smith

N. Amer. Sagittaria. 32, plate 15, figs. 1–4. 1894.

Treatment appears in FNA Volume 22.

Herbs, annual, to 60 cm; rhizomes absent; stolons present; corms present. Leaves submersed, phyllodial, lenticular, to nearly terete, 12–53 × 0.3–0.7 cm; rare stranded plants without expanded leaf-blades. Inflorescences racemes, of 2–7 whorls, floating or emersed, to 16 × 4 cm; peduncles 13.5–28 cm; bracts connate more than ¼ total length, ovate to lanceolate, 1.5–2 mm, delicate, not papillose; fruiting pedicels spreading to reflexed in flower and fruit, cylindric, 1.5–6.5 cm. Flowers 1.5–5 cm diam.; sepals spreading in staminate, appressed to spreading in flower and fruit in pistillate, often enclosing flower or fruiting head; filaments dilated, longer than anthers, glabrous; pistillate pedicellate, without ring of sterile stamens. Fruiting heads 0.4–0.6 cm diam; achenes oblanceoloid to obovoid, not abaxially keeled, 1.5 × 1 mm, beaked; faces not tuberculate, wings absent, glands absent; beak lateral, erect, 1.1 mm.


Phenology: Flowering summer–fall.
Habitat: Streams and lakes
Elevation: 1500–2000 m

Discussion

Sagittaria demersa was known previously only from central Mexico. It is known in the United States from three recent collections taken in northern New Mexico.

Selected References

None.

Lower Taxa

None.
... more about "Sagittaria demersa"
1.5 cm15 mm <br />0.015 m <br /> (?) +
keeled;oblanceoloid;obovoid +
papillose +  and smooth +
Obtuse (?) +  and Acute (?) +
Robert R. Haynes +  and C. Barre Hellquist +
J. G. Smith +
attenuate;hastate or sagittate +
1.1 cm11 mm <br />0.011 m <br /> (?) +
linear +  and obovate +
more than ¼ total length +
not papillose +
ovate +  and lanceolate +
N.Mex. +  and c Mexico +
1500–2000 m +
u--shaped +
not tuberculate +
0.4 cm4 mm <br />0.004 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
pistillate +  and staminate +
1.5 cm15 mm <br />0.015 m <br /> (5 cm50 mm <br />0.05 m <br />) +
appressed;spreading +
hypogynous +
pistillate +  and staminate +
appressed;spreading +
cylindric +
1.5 cm15 mm <br />0.015 m <br /> (6.5 cm65 mm <br />0.065 m <br />) +
Streams and lakes +
decumbent +  and floating +
0 cm0 mm <br />0 m <br /> (16 cm160 mm <br />0.16 m <br />) +
emersed +  and floating +
0 cm0 mm <br />0 m <br /> (4 cm40 mm <br />0.04 m <br />) +
petiolate +  and sessile +
12cm;53cm +
lenticular;nearly terete +
0.3 cm3 mm <br />0.003 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
decumbent +  and floating +
submersed +, floating +  and emersed +
ascending +  and recurved +
13.5 cm135 mm <br />0.135 m <br /> (28 cm280 mm <br />0.28 m <br />) +
deciduous +
terete +  and triangular +
Flowering summer–fall. +
not radiating +  and arranged +
N. Amer. Sagittaria. +
decumbent +  and floating +
persistent +
sculptured +
herbaceous;leathery +
Lophotocarpus +
Sagittaria demersa +
Sagittaria +
species +
white;brown +
plant +  and herb +
emersed +  and submersed +
glabrous +  and sparsely pubescent +
bracteolate +  and branching +