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callitriche des marais, spring water-starwort, vernal water-starwort

effluent water-starwort, water starwort, wheel fruit water-starwort

Stem

and leaf scales present.

and leaf scales present.

Leaves

connate at base, ± linear, tapering strongly from near base or spatulate, 2.5–9 × 0.3–5 mm, 1+-veined.

connate at base, ± parallel-sided, 5.2–9.1 × 0.1–0.9 mm, 1+-veined.

Inflorescences

bracts caducous, sometimes persistent.

bracts persistent.

Pedicels

0–0.2 mm in fruit.

0–0.5 mm in fruit.

Flowers

usually 1 staminate and 1 pistillate in 1 axil opposed by 1 pistillate;

styles erect or spreading;

pollen yellow.

usually 1 staminate and 1 pistillate in each axil;

styles spreading;

pollen yellow.

Schizocarps

obovoid, usually widest distal to middle, 0.8–1.4 × 0.6–1.4 mm, longer than wide, sometimes as long as wide;

mericarps black, not swollen, not winged, winged only at apex, or winged throughout but widest at apex, wings straight, 0.03–0.1 mm wide.

1–1.2 × 1.1–1.3 mm, ± as long as wide;

mericarps black, not swollen, evenly winged throughout, wings straight, 0.05–0.1 mm wide.

2n

= 20.

= 40.

Callitriche palustris

Callitriche trochlearis

Phenology Flowering May–Oct. Flowering Apr–Jul.
Habitat Fast-flowing rivers and streams, backwaters, ditches, swamps, Sphagnum bogs, lakes, ponds, springs, seepages. Vernal and perennial pools, ditches.
Elevation 0–3600 m. (0–11800 ft.) 0–2000 m. (0–6600 ft.)
Distribution
from FNA
AK; AZ; CA; CO; CT; DE; IA; ID; IL; MA; ME; MI; MN; MT; ND; NE; NH; NJ; NM; NV; NY; OR; PA; RI; SD; TX; UT; VT; WA; WI; WY; AB; BC; MB; NB; NF; NT; NU; ON; PE; QC; SK; YT; SPM; Greenland; Mexico (Chihuahua, San Luis Potosí); Eurasia [Introduced in Australia]
[WildflowerSearch map]
[BONAP county map]
from FNA
CA; OR
[WildflowerSearch map]
[BONAP county map]
Discussion

Callitriche palustris has been included on the Composite List of Weeds maintained by the Weed Science Society of America (http://wssa.net/wssa/weed/composite-list-of-weeds/); its inclusion seems unwarranted.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Callitriche trochlearis occurs in northwestern and central-western California plus western Oregon.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 17, p. 53. FNA vol. 17, p. 54.
Parent taxa Plantaginaceae > Callitriche Plantaginaceae > Callitriche
Sibling taxa
C. brutia, C. fassettii, C. hermaphroditica, C. heterophylla, C. longipedunculata, C. marginata, C. pedunculosa, C. peploides, C. stagnalis, C. stenoptera, C. terrestris, C. trochlearis
C. brutia, C. fassettii, C. hermaphroditica, C. heterophylla, C. longipedunculata, C. marginata, C. palustris, C. pedunculosa, C. peploides, C. stagnalis, C. stenoptera, C. terrestris
Synonyms C. palustris var. stenocarpa, C. palustris var. verna, C. stenocarpa, C. verna
Name authority Linnaeus: Sp. Pl. 2: 969. (1753) Fassett: Rhodora 53: 194. (1951)
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