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Benghal dayflower, dayflower, jio, tropical spiderwort

climbing dayflower, spreading dayflower

Habit Herbs, annual. Herbs, perennial or annual, spreading.
Roots

thin, rhizomes short, subterranean, bearing cleistogamous flowers produced from base of plant.

Stems

ascending to decumbent or occasionally scrambling.

decumbent to scandent.

Leaves

leaf sheaths, not auriculate, often with red hairs at summit;

blade ovate to lanceolate-elliptic, (1–)2–9(–11) × 1–3(–4.5) cm, apex rounded, obtuse or acute, pubescent.

blade narrowly lanceolate to lanceolate-oblong, lanceolate-elliptic or ovate, 1.5–14 × 0.5–3.3 cm, margins scabrous, apex acute to acuminate, glabrous.

Inflorescences

distal cyme often exserted and 1-flowered, sometimes vestigial;

spathes often clustered, subsessile (peduncles 1–3.5 mm), funnelform, 0.5–1.5(–2) cm, margins connate basally, pubescent.

distal cyme 1–several-flowered, usually exserted;

spathes solitary, bright green, without contrasting veins, pedunculate, usually distinctly falcate, (0.5–)0.8–4 × 0.4–1.2(–1.4) cm, margins distinct, glabrous or scabrous, sometimes also sparsely ciliate or ciliolate basally, apex usually acuminate, usually glabrous or nearly so;

peduncles 0.5–2(–4) cm.

Flowers

chasmogamous flowers bisexual and staminate, subterranean cleistogamous flowers bisexual;

petals of staminate flowers all blue (rarely lilac), proximal smaller;

lateral stamen filaments not winged;

staminodes 2–3;

antherodes yellow, cruciform;

pollen white;

medial stamen pollen yellow.

bisexual and staminate;

petals all blue (rarely all lavender), proximal petal smaller;

medial stamen anther connective usually with transverse band of violet;

staminodes 2–3;

antherodes yellow, medial often absent or vestigial, cruciform.

Capsules

3-locular, 2-valved, 4–6 mm.

3-locular, 2-valved, 4–6.3 mm.

Seeds

5, brown or blackish, seeds of adaxial locule 1.7–2.5 mm, shallowly reticulate, farinose.

5 (or less through abortion), brown, 2–2.8(–3.2) × 1.4–1.8 mm, deeply reticulate.

2n

= 22.

Commelina benghalensis

Commelina diffusa

Phenology Flowering spring–fall.
Habitat Citrus plantations, fields, yards, and other cultivated and disturbed sites
Distribution
from FNA
CA; FL; GA; LA; neotropics; native; paleotropics [Introduced in North America]
[WildflowerSearch map]
[BONAP county map]
from FNA
AL; AR; DC; FL; GA; IL; IN; KS; KY; LA; MD; MO; MS; NC; OH; OK; SC; TN; TX; VA; Pantropical
[WildflowerSearch map]
[BONAP county map]
Discussion

Commelina benghalensis was first recognized and collected in California in 1980. The California plants are approximately hexaploid and represent a separate and much later introduction than the southeastern plants. The species is federally listed as an Obnoxious Weed.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

The name Commelina nudiflora Linnaeus has been incorrectly used for this species.

Varieties 4 (2 in the flora).

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Key
1. Leaf blades 1.5–5(–8) × 0.5–1(–2.2) cm; medial anther connective with broad transverse violet band; capsules 5-seeded (occasionally less, by abortion)
var. diffusa
1. Leaf blades 6–14 × 1–3.3 cm; medial anther connective without dark band; capsules typically 1–2-seeded
var. gigas
Source FNA vol. 22. FNA vol. 22.
Parent taxa Commelinaceae > Commelina Commelinaceae > Commelina
Sibling taxa
C. caroliniana, C. communis, C. dianthifolia, C. diffusa, C. erecta, C. forskaolii, C. gambiae, C. virginica
C. benghalensis, C. caroliniana, C. communis, C. dianthifolia, C. erecta, C. forskaolii, C. gambiae, C. virginica
Subordinate taxa
C. diffusa var. diffusa, C. diffusa var. gigas
Name authority Linnaeus: Sp. Pl. 1: 41. (1753) Burman f.: Flora Indica. nec non Prodromus Florae Capensis 18, plate 7, fig. 2. (1768)
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