The green links below add additional plants to the comparison table. Blue links lead to other Web sites.
enable glossary links

callitriche des eau× stagnantes, pond water-starwort

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

Stem

and leaf scales present.

and leaf scales present.

Leaves

connate at base, obovate-spatulate to ± round, 4–9 × 1–4 mm, 1+-veined.

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

Inflorescences

bracts persistent.

bracts caducous, sometimes persistent.

Pedicels

0–0.2 mm in fruit.

0–0.2 mm in fruit.

Flowers

solitary;

styles erect;

pollen yellow.

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

styles erect or spreading;

pollen yellow.

Schizocarps

1.2–1.8 × 1–1.7 mm, ± as long as wide;

mericarps pale grayish brown, not swollen, winged throughout, wings straight, 0.1–0.5 mm wide.

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.

2n

= 10.

= 20.

Callitriche stagnalis

Callitriche palustris

Phenology Flowering May–Oct. Flowering May–Oct.
Habitat Standing water, stream margins, backwaters, ponds, pools, ditches. Fast-flowing rivers and streams, backwaters, ditches, swamps, Sphagnum bogs, lakes, ponds, springs, seepages.
Elevation 0–1500 m. (0–4900 ft.) 0–3600 m. (0–11800 ft.)
Distribution
from FNA
AL; CA; CT; MA; MD; ME; MO; MT; NJ; NY; OR; PA; VA; WA; WI; BC; NF; QC; SPM; Europe [Introduced in North America; introduced also in Australia]
[WildflowerSearch map]
[BONAP county map]
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]
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.)

Source FNA vol. 17, p. 54. FNA vol. 17, p. 53.
Parent taxa Plantaginaceae > Callitriche Plantaginaceae > Callitriche
Sibling taxa
C. brutia, C. fassettii, C. hermaphroditica, C. heterophylla, C. longipedunculata, C. marginata, C. palustris, C. pedunculosa, C. peploides, C. stenoptera, C. terrestris, C. trochlearis
C. brutia, C. fassettii, C. hermaphroditica, C. heterophylla, C. longipedunculata, C. marginata, C. pedunculosa, C. peploides, C. stagnalis, C. stenoptera, C. terrestris, C. trochlearis
Synonyms C. palustris var. stenocarpa, C. palustris var. verna, C. stenocarpa, C. verna
Name authority Scopoli: Fl. Carniol. ed. 2, 2: 251. (1772) Linnaeus: Sp. Pl. 2: 969. (1753)
Web links