Directory       News       Site Map       Home
    Jepson eFlora: Taxon page
Key to families | Table of families and genera

Previous taxon 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 |
Previous taxon


Thomas J. Rosatti, except as noted

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 tropics, subtropical South America, southern 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.: California. (Greek: ring gland, from nectary) [Sipes & Wolf 1997 Amer J Bot 84:401–409]

C. humilis Benth.
Perennial herb, ± 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 varieties as well. Therefore, the entire group merits further study.

Key to Cycladenia humilis

C. humilis var. jonesii (Eastw.) S.L. Welsh & N.D. Atwood
Plant generally glabrous, glaucous except inflorescence hairy. Flower: perianth with ± not interwoven hairs abaxially or at least on margins, corolla sparse-hairy adaxially, lobes 4–5 mm.
Shale slides; 2530 m. White and Inyo Mountains (Inyo Mtns); Utah, Arizona. Unpublished molecular evidence (Slakey, et al., 2011, pers. comm.) suggests that California members of var. jonesii belong instead either to var. venusta or to an undescribed taxon. Jul [Online Interchange]
Unabridged note: In Utah, evidently an obligate gypsomorph of ± dry conditions in which flowers are of 2 kinds (evidently, only as to size) within populations (A Utah Flora, Welsh et al., eds., 1993). One collection from California mentioned by Eastwood in protologue (Mark Kerr 3267, CAS, from Inyo Mountains; not seen); Alexander & Kellogg 3058 (UC1036093; 5 July 1942, also from Inyo Mtns), associated with card bearing sketch of flower, and "Cycladenia humilis var. alexandrae (sic), × 2, Alexander & Kellogg 3058, type" handwritten, possibly by Lauramay Dempster (name ined.), and "This is a new species. G.W. Gillett. Aug. 1958" handwritten above collection label.

Previous taxon: Cycladenia humilis var. humilis
Next taxon: Cycladenia humilis var. venusta


Name search

Citation for the whole project: Jepson Flora Project (eds.) 2013. Jepson eFlora,, accessed on Nov 27 2015
Citation for this treatment: [Author of taxon treatment] 2013. Cycladenia, in Jepson Flora Project (eds.) Jepson eFlora,, accessed on Nov 27 2015

Copyright © 2014 Regents of the University of California
We encourage links to these pages, but the content may not be downloaded for reposting, repackaging, redistributing, or sale in any form, without written permission from The Jepson Herbarium.

Geographic subdivisions indicated for the distribution of Cycladenia humilis var. jonesii 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 provide evidence for eFlora range revision or may have georeferencing or identification issues.
map of distribution 1
(Note: any qualifiers in the taxon distribution description, such as 'northern', 'southern', 'adjacent' etc., are not reflected in the map above, and in some cases indication of a taxon in a subdivision is based on a single collection or author-verified occurence).

View elevation by latitude chart
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 eFlora flowering time.