Jepson Herbarium
The University and Jepson Herbaria
University of California, Berkeley
Jepson eFlora: Taxon page
Vascular Plants of California
Key to families | Table of families and genera
Previous taxon Index to 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 |
Next taxon

Anulocaulis

RINGSTEM


Higher Taxonomy
Family: NyctaginaceaeView DescriptionDichotomous Key

Common Name: FOUR O'CLOCK FAMILY
Habit: Annual, perennial herb, subshrub, [shrub, tree], glabrous or hairy. Stem: often forked. Leaf: opposite, sessile or petioled, pairs generally unequal; blade generally entire. Inflorescence: generally forked; spike, head-like cluster, or umbel, flowers rarely 1, bracts forming a calyx-like involucre or not. Flower: bisexual, generally +- radial (bilateral), sometimes cleistogamous in some genera; perianth of 1 whorl, generally petal-like, bell- to trumpet-shaped, base hardened, tightly surrounding ovary in fruit, lobes 3--5, generally notched to +- lobed; stamens 1--many; ovary superior (appearing inferior due to hardened perianth base), style 1. Fruit: achene in hardened perianth base; round to +- flat; smooth, angled, ribbed, or winged; glabrous, hairy, or glandular.
Genera In Family: 30 genera, 350 species: warm regions, especially America; some ornamental (Bougainvillea; Mirabilis, four o'clock).
eFlora Treatment Author: Andy Murdock, except as noted
Scientific Editor: Thomas J. Rosatti.
Anulocaulis
Habit: Perennial herb from thick caudex. Stem: little-branched, erect, > 7 mm diam; internodes with sticky brown ring. Leaf: few, +- in lower 1/2, petioled; blade oblong to round, thick. Inflorescence: openly branched; flowers in head, raceme, or umbel-like cluster; bracts 1--3, free, not forming involucre. Flower: perianth funnel-shaped; stamens 3, exserted; stigma +- spheric, exserted. Fruit: inconspicuously 10-ribbed, glabrous.
Species In Genus: 5 species: especially Chihuahuan Desert, northeastern Mexico. Etymology: (Latin: ring stem, from sticky ring on internode) Note: Closely related to Boerhavia.
Jepson eFlora Author: Andy Murdock & Richard Spellenberg
Reference: Spellenberg 2003 FNANM 4:28--30
Index of California Plant Names (ICPN; linked via the Jepson Online Interchange)

Previous taxon: Allionia incarnata var. villosa
Next taxon: Anulocaulis annulatus


Please use this Google Form for Contact/Feedback

Citation for this treatment: Andy Murdock & Richard Spellenberg 2012, Anulocaulis, in Jepson Flora Project (eds.) Jepson eFlora, https://ucjeps.berkeley.edu/eflora/eflora_display.php?tid=8784, accessed on February 07, 2025.

Citation for the whole project: Jepson Flora Project (eds.) 2025, Jepson eFlora, https://ucjeps.berkeley.edu/eflora/, accessed on February 07, 2025.