Jepson eFlora
Key to families | Table of families and genera

Key to Apocynaceae

View taxon page for Apocynaceae

1. Filaments fused into filament column, generally with 5 free or fused, ± elaborate appendages abaxially; anthers fused into anther head around and fused to pistil head; pollen removed in pairs of pollinia; nectaries in stigmatic chambers (genera formerly treated as Asclepiadaceae)

2. Filament column ± without appendages ..... Funastrum utahense

2' Filament column with appendages

3. Filament column appendages fused into 5-lobed, cup- or plate-like structure around anther head ..... MATELEA

3' Filament column appendages free

4. Filament column appendages hollow (possibly due to complete fusion of margins); ring of tissue at base of corolla present ..... FUNASTRUM

4' Filament column appendages solid (margins converging, nearly meeting or not, not fused); ring of tissue at base of corolla 0

5. Filament column appendage margins converging but not nearly meeting abaxially; flowers in raceme- or panicle-like cymes; stem twining ..... ARAUJIA

5' Filament column appendage margins converging and meeting or nearly meeting adaxially (to form hood); flowers in umbel-like cymes; stem prostrate to erect ..... ASCLEPIAS

1' Filaments free, unappendaged; anthers free, lying against, adherent to pistil head or not; pollen ± free, not removed in pollinia; nectaries 0 or near ovaries (genera formerly treated as Apocynaceae)

6. Seed glabrous; stamens attached near top of corolla tube, near level of stigma

7. Leaves alternate to subwhorled; plant erect ..... AMSONIA

7' Leaves opposite to subopposite; plant erect or sprawling

8. Corolla pink, tube ± cylindric; plant erect ..... [Catharanthus roseus]

8' Corolla purple-blue (white), tube funnel-shaped; plant sprawling ..... VINCA

6' Seed with tuft of long hairs at 1 end; stamens attached at or near base of corolla tube, below level of stigma, or appearing so

9. Plant shrub, small tree; leaves generally whorled or subwhorled (opposite); nectaries 0; sap not milky ..... NERIUM

9' Plant perennial herb; leaves opposite; nectaries 5, free or fused; sap milky

10. Leaves, stems, roots not fleshy; flower < 8 mm, in generally >> 6-flowered cyme; nectaries 5, free ..... APOCYNUM

10' Leaves, stems, roots fleshy; flower > 15 mm, in 2–6-flowered cyme; nectaries 5, fused into a 5-lobed disk ..... CYCLADENIA


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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