Key to Callitriche

View taxon page for Callitriche

(For a list of species in Callitriche, use the above link.)

Jepson Manual glossary definitions can be seen by moving your cursor over words underlined with dots.

1. Leaf dark green, contrasting strongly with pale stem; leaves all ± 

linear 

Elongate, with nearly parallel sides; narrower than elliptic or oblong.

or tapering from near base; no leaves with > 1 central vein ..... C. fassettii

1' Leaf pale green and not contrasting strongly with stem; leaves ± linear and vein 1, to broad, petioled, and veins > 1

2. Fruit 

wing 

1. Thin, flat extension or appendage of a surface or margin. 2. In many members of Fabaceae and in some other groups, each of two lateral petals.

0 or winged only distal to middle

3. Fruit length >= width, wing distal to middle only or 0; fruit with evident lines of cells on faces ..... C. palustris

3' Fruit length ± = width, generally wing 0; cells on fruit faces obscure ..... C. heterophylla

4. Fruit 0.8–1.4 mm ..... var. bolanderi

4' Fruit 0.6–0.8 mm ..... var. heterophylla

2' Fruit winged from tip to base

5. Peduncle in fruit 2–25 mm

6. Fruit length >= width, 1–1.2 mm, 0.9–1.2 mm wide ..... C. longipedunculata

6' Fruit length < width, 0.7–1 mm, 1.1–1.4 mm wide ..... C. marginata (2)

5' Peduncle in fruit 0–1 mm

7. Mature fruit gray-brown, not contrasting strongly with wing ..... C. stagnalis

7' Mature fruit dark brown to black, contrasting strongly with translucent wing

8. Fruit length < width, 0.7–1 mm, 1.1–1.4 mm wide ..... C. marginata (2)

8' Fruit length = width, 1–1.5 mm, 1–1.5 mm wide ..... C. trochlearis

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Citation for the whole project: Jepson Flora Project (eds.) . Jepson eFlora, https://ucjeps.berkeley.edu/eflora/ [accessed on ]

Citation for an individual treatment: [Author of taxon treatment] [year]. [Taxon name] in Jepson Flora Project (eds.) Jepson eFlora, [URL for treatment]. Accessed on .

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