Callitriche trochlearis |
Callitriche hermaphroditica |
|
---|---|---|
effluent water-starwort, water starwort, wheel fruit water-starwort |
autumn water-starwort, autumnal water-starwort, callitriche hermaphrodiate, northern water-starwort, scarlet waterstarwort |
|
Stem | and leaf scales present. |
and leaf scales absent. |
Leaves | connate at base, ± parallel-sided, 5.2–9.1 × 0.1–0.9 mm, 1+-veined. |
not connate at base, ± linear, tapering from base, (7–)7.6–11.5 × 0.9–1.4 mm, 1-veined. |
Inflorescences | bracts persistent. |
bracts absent. |
Pedicels | 0–0.5 mm in fruit. |
0 mm in fruit. |
Flowers | usually 1 staminate and 1 pistillate in each axil; styles spreading; pollen yellow. |
solitary; styles erect, later recurved; pollen colorless. |
Schizocarps | 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. |
1.1–1.9 × 1.2–2.4 mm, shorter than or as long as wide, sometimes longer than wide; mericarps dark brown, not swollen, winged throughout, wings straight, 0.2–0.8 mm wide, as wide as or wider than mericarp body. |
2n | = 40. |
= 6. |
Callitriche trochlearis |
Callitriche hermaphroditica |
|
Phenology | Flowering Apr–Jul. | Flowering Jul–Sep(–Nov). |
Habitat | Vernal and perennial pools, ditches. | Lakes, ponds, backwaters, ditches. |
Elevation | 0–2000 m. (0–6600 ft.) | 0–3000 m. (0–9800 ft.) |
Distribution |
CA; OR
|
AK; CO; ID; MT; NE; NJ; NY; OR; UT; VT; WI; WY; AB; BC; NF; NT; ON; QC; SK; Greenland; Eurasia
|
Discussion | Callitriche trochlearis occurs in northwestern and central-western California plus western Oregon. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Infraspecific divisions have been based on the size of fruit (for example, R. V. Lansdown 2006); assignment of North American populations to these taxa would be premature. Callitriche autumnalis Linnaeus is a superfluous renaming of C. hermaphroditica, with which it is homotypic (R. V. Lansdown and C. E. Jarvis 2004). Callitriche fassettii, C. hermaphroditica, and C. stenoptera are morphologically very close; however, C. hermaphroditica always has sessile fruit, whereas the fruit of both the other species may be pedicellate. The mericarp wing of C. stenoptera is consistently very narrow and that of C. fassettii is slightly wider than that of C. hermaphroditica, which is generally wide, particularly at the apex. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 17, p. 54. | FNA vol. 17, p. 51. |
Parent taxa | Plantaginaceae > Callitriche | Plantaginaceae > Callitriche |
Sibling taxa | ||
Synonyms | C. bifida, C. palustris var. bifida | |
Name authority | Fassett: Rhodora 53: 194. (1951) | Linnaeus: Cent. Pl. I, 31. (1755) |
Web links |
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