Jepson eFlora
Key to families | Table of families and genera

Key to Hydrocharitaceae

View taxon page for Hydrocharitaceae

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

1. Plants floating (rooted in mud when stranded); leaves (when floating) with swollen spongy cells abaxially ..... LIMNOBIUM

1' Plants submersed to emergent; leaves without swollen spongy cells abaxially

2. Leaves basal, petioled, alternate, lower, submersed blades elliptic to ovate, upper, floating or emergent blades ovate to cordate or reniform – flower bisexual, emergent ..... [OTTELIA]

2' Leaves cauline, sessile, opposite to whorled, blade oblong or linear

3. Perianth 0; leaves ± opposite to ± whorled; seeds smooth or pitted ..... NAJAS

3' Perianth present; leaves opposite or generally whorled; seeds smooth

4. Leaves 1.2–4 cm, 2–5 mm wide; staminate flowers 2–3, petals 8–10 mm ..... EGERIA

4' Leaves < 1.5(2) cm, < 3 mm wide; staminate flowers 1, petals generally <= 5 mm

5. Leaves often 2 per node proximally, 3–7 distally, minutely serrate, midrib abaxially ± smooth ..... ELODEA

5' Leaves generally 4–8 per node, coarsely serrate, midrib abaxially prickled or not ..... HYDRILLA


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