Jepson Herbarium
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Indexes to all accepted names and synonyms: | A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z |

Annual, perennial herb, shrub, tree, often vine; sap generally milky.
Leaf: simple, alternate, opposite, subwhorled to whorled, entire; stipules 0 or small, finger-like.
Inflorescence: axillary or terminal, cyme, generally umbel- or raceme-like, or flowers 1–2.
Flower: bisexual, radial; perianth parts, especially petals, overlapped, twisted to right or left, at least in bud; sepals generally 5, fused at base, often reflexed, persistent; petals generally 5, fused in basal ± 1/2; stamens generally 5, attached to corolla tube or throat, alternate lobes, free or fused to form filament column and anther head, filament column then generally with 5 free or fused, ± elaborate appendages abaxially, pollen ± free or removed in pairs of pollinia; nectaries 0 or near ovaries, then 2 or 5[10], or in stigmatic chambers; ovaries 2, superior or ± so, free [ fused]; style tips, stigmas generally fused into massive pistil head.
Fruit: 1–2 follicles, ( capsule), [ berry, drupe].
Seed: many, often with tuft of hairs at 1 or both ends.
200–450 genera, 3000–5000 species: all continents, especially tropical, subtropical South America, s Africa; many ornamental (including Asclepias, Hoya, Nerium, Plumeria, Stapelia); cardiac glycosides, produced by some members formerly treated in Asclepiadaceae, used as arrow poisons, in medicine to control heart function, and by various insects for defense. [Fishbein 2001 Ann Missouri Bot Gard 88:603–623] Asclepiadaceae ("asclepiads"), although monophyletic, included in Apocynaceae because otherwise the latter is paraphyletic. Complexity of floral structure, variation in asclepiads arguably greatest among all angiosperms. Pattern of carpel fusion (carpels free in ovule-bearing region, fused above), present ± throughout Apocynaceae (in broad sense), nearly unknown in other angiosperms. Base chromosome number generally 11; abundance of latex, generally small size of chromosomes evidently have impeded cytological investigations. —Scientific Editor: Bruce G. Baldwin.
Unabridged references: [Civeyrel et al. 1998 Molec Phylogen Evol 9:517–527; Rosatti 1989 J Arnold Arbor 70:307–401]

Key to Apocynaceae

1 sp.: CA. (Greek: ring gland, from nectary) [Sipes & Wolf 1997 Amer J Bot 84:401–409]

Perennial, ± erect, 6–12 cm, fleshy (including large root), herbage tomentose to generally glabrous, glaucous.
Leaf: opposite, 2–5 pairs, < 9 cm; petiole < to > blade; blade ovate or ± round, base ± truncate to tapered.
Inflorescence: cyme, 2–6-flowered.
Flower: > 15 mm; calyx lobes narrow-triangular; corolla 15–20 mm, funnel-shaped, with 5 ± round appendages behind anthers, rose-purple, lobes obovate or round, margins wavy; filaments free, appearing to be attached at base of corolla tube but fused to it up to level of stigma, unappendaged, hairy, anthers forming cone around but free from stigma, each partly sterile, sharply sagittate, pollen ± free; nectaries 5, fused into a 5-lobed disk around but not exceeding ovaries; style thread-like; stigma skirted at base.
Fruit: 3–5 cm.
Seed: with tuft of long hairs at 1 end.
2n=14. Varieties possibly untenable, merit study. [Online Interchange]
Unabridged note: Given that hairiness within Cycladenia humilis var. humilis appears to be governed by a single gene (thus reducing Cycladenia humilis var. tomentosa to synonymy under Cycladenia humilis var. humilis), doubt is cast on the hair characters separating Cycladenia humilis var. humilis from Cycladenia humilis var. venusta and Cycladenia humilis var. jonesii as well; given that corolla lobe length in Cycladenia humilis var. humilis overlaps that in Cycladenia humilis var. venusta and Cycladenia humilis var. jonesii, doubt is cast on the characters separating these vars. as well. Therefore, the entire group merits further study.

Plant generally glabrous, glaucous, less often dense-tomentose.
Flower: perianth glabrous ( tomentose) abaxially; corolla glabrous or papillate adaxially, lobes (5)7–9(11) mm.
Loose gravel or sand, talus slopes, often with Pinus ponderosa; 1200–2800 m. Klamath Ranges, High North Coast Ranges, High Cascade Range, n High Sierra Nevada (Plumas, Sierra cos.), Outer South Coast Ranges (Santa Lucia Range).

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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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Bioregions in which taxon occurs	Red area (if present) is the part of the bioregion lying between the upper and lower elevation limits of the taxon; markers link to CCH specimen records. If the markers are obscured, reload the page [or change window size and reload]. Yellow markers indicate records that may have georeferencing or identification issues.
Chart based on elevation range in Manual and elevations and coordinates of CCH records. Data provided by the participants of the Consortium of California Herbaria. Note: About half of the CCH records include both elevation and coordinates.	Map made in collaboration with Scott Loarie. Data provided by the participants of the Consortium of California Herbaria. View all CCH records   CCH collections by month Duplicates counted once; synonyms included. Species do not include records of infraspecific taxa. Blue line denotes Manual flowering time.