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

Nuttall's 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, obovate-oblanceolate to spatulate, (2.2–)2.7–5.7 × 0.7–2 mm, 2+-veined.

Inflorescences

bracts caducous, sometimes persistent.

bracts absent.

Pedicels

0–0.2 mm in fruit.

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 1 axil opposed by 1 pistillate, rarely both pairs at an axil with 1 staminate and 1 pistillate;

styles loosely ascending or ± reflexed;

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.

0.8–1 × 0.9–1.3 mm, shorter than wide;

mericarps black, not swollen, winged throughout, wings curled, giving appearance of thickened margins, 0.06–0.15 mm wide.

2n

= 20.

= 20.

Callitriche palustris

Callitriche pedunculosa

Phenology Flowering May–Oct. Flowering Feb–Jun(Sep–Oct).
Habitat Fast-flowing rivers and streams, backwaters, ditches, swamps, Sphagnum bogs, lakes, ponds, springs, seepages. Seasonally wet sandy soils, in or shaded by woodlands.
Elevation 0–3600 m. (0–11800 ft.) 0–100 m. (0–300 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
AL; LA; MS; TX
[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 nuttallii Torrey is an illegitimate, superfluous name that applies here. Torrey proposed it as a replacement for C. pedunculosa Nuttall based on the mistaken belief that the name by Nuttall was a later homonym of one by Arnott; the purported name by Arnott does not exist.

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

Source FNA vol. 17, p. 53. 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. 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. peploides, C. stagnalis, C. stenoptera, C. terrestris, C. trochlearis
Synonyms C. palustris var. stenocarpa, C. palustris var. verna, C. stenocarpa, C. verna
Name authority Linnaeus: Sp. Pl. 2: 969. (1753) Nuttall: Trans. Amer. Philos. Soc., n. s. 5: 140. (1835)
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