Flora Indica. nec non Prodromus Florae Capensis 18, plate 7, fig. 2. 1768.
Herbs, perennial or annual, spreading. Stems decumbent to scandent. Leaves: 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 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 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, 4–6.3 mm. Seeds 5 (or less through abortion), brown, 2–2.8(–3.2) × 1.4–1.8 mm, deeply reticulate.
Ala., Ark., D.C., Fla., Ga., Ill., Ind., Kans., Ky., La., Md., Miss., Mo., N.C., Ohio, Okla., S.C., Tenn., Tex., Va., Pantropical.
The name Commelina nudiflora Linnaeus has been incorrectly used for this species.
Varieties 4 (2 in the flora).
|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)||Commelina diffusa var. diffusa|
|1||Leaf blades 6–14 × 1–3.3 cm; medial anther connective without dark band; capsules typically 1–2-seeded||Commelina diffusa var. gigas|