Asiatic Dayflower

Commelina communis var. ludens (Miquel) C. B. Clarke is distinguished by its darker flowers, antherodes with maroon centers (instead of entirely yellow), distalmost cyme less well developed and usually not producing a flower, and spathes proportionally broader. I have not found it possible to separate this regularly from C. communis var. communis, which also occurs in the flora. A variegated form of C. communis var. ludens, forma aureostriata MacKeever, occurs spontaneously and has been noted from Arkansas, Kentucky, Louisiana, Maryland, North Carolina, Texas, and Virginia.

A medicinal herb with febrifugal, anti-inflammatory, and diuretic effects; also used for relieving sore throat and tonsilitis.

Herbs, annual, erect to decumbent. Roots at proximal nodes. Stems diffusely branched. Leaves: blade narrowly lanceolate to ovate-elliptic, 5--12 ´ 1--4 cm, apex acute to acuminate. Inflorescences: distal cyme usually vestigial, included, sometimes 1-flowered, exserted; spathes solitary, green, paler or whitish basally with contrasting, dark green veins, pedunculate, usually not falcate, 1.5--3(--3.5) ´ 0.8--1.3(--1.8) cm, margins distinct, scabrous, not ciliate, apex acute to acuminate, glabrous to puberulent; peduncles 0.8--3.5(--5) cm. Flowers bisexual (rarely staminate); proximal petal paler or white, very reduced, distal petals blue to bluish purple; staminodes 3; antherodes yellow sometimes with central maroon spot, cruciform. Capsules 2-locular, 2-valved, 4.5--8 mm. Seeds 4, brown, (2--)2.5--4.2 ´ 2.2--3 mm, rugose pitted-reticulate.

Herbs annual. Stems creeping, diffuse, numerous branched, to more than 1 m, glabrous proximally, puberulent distally. Leaf sheaths glabrous; leaf blade lanceolate to ovate-lanceolate, 3--9 × 1.5--2 cm, glabrous. Involucral bracts borne opposite leaves, with 1.5--4 cm long stalk, cordate, folded, 1.2--2.5 cm, often hirsute-ciliate, apex acute. Proximal branch of cincinni with peduncle ca. 8 mm and 1 or 2 male flowers, distal branch with short peduncle and 3 or 4 bisexual flowers, nearly included in involucral bracts; pedicels ca. 3 mm at anthesis, curved and less than 6 mm in fruit. Sepals ca. 5 mm, membranous. Petals dark blue, 9--10 mm except proximal one ca. 5 mm. Capsule ellipsoid, 5--7 mm, 2-valved. Seeds 2 per valve, brown-yellow, semiellipsoid, 2--3 mm, flat on 1 surface, irregularly pitted, truncate at 1 end.

Flowering summer--fall. Weedy and waste places; edges of fields, woods, and marshes, often in thick herbaceous vegetation; occasionally in woods; introduced; Ont., Que.; Ala., Ark., Conn., Del., D.C., Ga., Ill., Ind., Iowa, Kans., Ky., La., Md., Mass., Mich., Minn., Miss., Mo., Nebr., N.J., N.Y., N.C., Ohio, Okla., Pa., R.I., S.C., S.Dak., Tenn., Tex., Va., W.Va., Wis.; native, Asia.

Humid places. Throughout China except for Qinghai, Xinjiang, and Xizang. [Cambodia, Japan, Korea, Laos, ?Malaysia, Russia (Far East), Thailand, Vietnam].

Commelina coreana H. Léveillé & Vaniot.