Lactuca indica L.

Compositae, G. V. Pope. Flora Zambesiaca 6:1. 1992

Morphology General Habit

A stout erect leafy annual or biennial herb up to c. 1.5(4) m. tall.

Morphology Stem

Stems solitary, branching above, glabrous.

Morphology Leaves

Leaves cauline sessile, not or scarcely auriculate, glabrous; lower leaves up to c. 22 x 14 cm., pinnatipartite, narrowly ovate to broadly elliptic in outline, remotely 2–5-lobed, the terminal lobe up to c. 9.5 x 2.5 cm. lanceolate, lateral lobes up to c. 5.5 x 1 cm. lorate; upper leaves smaller, undivided and lanceolate to linear-lanceolate, sometimes lobed.

Morphology Reproductive morphology Inflorescences Synflorescence

Synflorescence paniculate; branches ascending, glabrous with ovate to narrowly lanceolate bracts.

Morphology Reproductive morphology Inflorescences Capitulum

Capitula numerous, stalked; stalks up to c. 2.5 cm. long, imbricately bracteolate particularly when young; involucres 8–10 x 3.5–4 mm., cylindric at time of flowering, increasing to c. 14 x 7 mm. and becoming pyriform in fruiting capitula.

Morphology Reproductive morphology Inflorescences Bracts Phyllaries

Phyllaries 4–5-seriate, glabrous; the outermost 2–5 mm. long, ovate; the innermost to c. 14 mm. long, lorate-lanceolate.

Morphology Reproductive morphology Flowers Florets

Florets 20–28 per capitulum; corollas yellow 13–15 mm. long, tube slender, cylindric, pubescent about the mouth; ligule c. 7–9 x 1.5–2 mm., lorate, glabrous.

Morphology Reproductive morphology Fruits

Achenes dark-brown or black 4.5–5 x 1.5–2 mm. including a c. 1 mm. long paler-coloured beak, flattened-ellipsoid, ± winged on the margins and narrowly 1(2)-ribbed on each face, glabrous; pappus several-seriate, of white barbellate setae c. 7 mm. long.