The Jepson Herbarium
		University of California, Berkeley
			Jepson Herbarium

Key to Araceae

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

1. Plants not reduced, clearly differentiated into stems, leaves; floating aquatics or not; inflorescence a spike, conspicuous; perianth parts 0, 4, 6; stamens 0, 2, 3, 4, 6 (genera treated as Araceae in TJM (1993), minus Acorus)

2. Plant aquatic, floating; inflorescence ± sessile, inconspicuous among basal leaves ..... [PISTIA]

2' Plant terrestrial or near edge of water; inflorescence peduncled, ± conspicuous

3. Petiole < leaf blade; inflorescence bract yellow ..... LYSICHITON

3' Petiole ± >= leaf blade; inflorescence bract sometimes pale yellow-green but not yellow

4. Peduncle ± >= leaf; inflorescence bract white both surfaces (tip generally pale green) ..... ZANTEDESCHIA

4' Peduncle generally << leaf; inflorescence bract abaxially pale yellow-green, adaxially ± white to pale yellow-green or dark purple, or green both surfaces (margins pale green to white or not)

5. Inflorescence sterile in ± upper 1/2, flowers only in lower 1/2; inflorescence bract abaxially pale yellow-green, adaxially ± white to pale yellow-green or dark purple ..... ARUM

5' Inflorescence fertile throughout; inflorescence bract green both surfaces (margins pale green to white or not) ..... [Peltandra virginica]

1' Plants much reduced, not differentiated into stems, leaves; floating aquatics; inflorescence 1-flowered, inconspicuous; perianth parts 0; stamens 1, 2 (genera treated as Lemnaceae in TJM (1993))

6. Roots 0 (see also Lemna trisulca)

7. Plant body ± cylindric to nearly spheric, 0.4–1.3 mm ..... WOLFFIA

7' Plant body flat, linear to oblong, 3–10 mm ..... WOLFFIELLA

6' Roots present

8. Root generally 1 ..... LEMNA

8' Roots generally 2–16

9. Roots generally 2–7; plant body 3–5 mm, veins 3–7; winter buds 0 ..... LANDOLTIA

9' Roots generally 7–16; plant body 5–10 mm, veins 7–12; winter buds produced ..... SPIRODELA

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Citation for the whole project: Jepson Flora Project (eds.) [year] Jepson eFlora, http://ucjeps.berkeley.edu/IJM.html [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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