Lactuca indica L.

Global description
 
Lactuca indica has an erect growth habit, reaching 0.5 to 2 m tall, with milky latex. The robust, glabrous stem can be simple or branched. The leaves are alternate, simple. The basal leaves are deeply lobed and serrated, larger than the cauline leaves becoming lanceolate, entire, with only a few tines at the base. The inflorescence is terminal or branched, composed of cylindrical or spread pale yellow heads. The flowers that form heads are pale yellow, all spread out to the periphery. The fruits are elliptical, highly flattened, blackish brown in colour and topped with long white bristles.
 
First leaves
 
The first leaves are simple, alternate, arranged in rosette. The entire lamina is spatulated and attenuated at the base in a pseudo-petiole. Marge with few coarse tines. Glabrous faces.
 
General habit
 
Erect herbaceous plant, 0.50 to 2 m high and simple or branched stem.
 
Underground system
 
The plant has a deep taproot system.
 
Stem
 
The stem is cylindrical, full and smooth, sometimes light green dotted with red, emitting a white latex when broken.
 
Leaf
 
The leaves are alternate, simple, sessile. Basal leaves lanceolate, usually deeply pinnately lobed, 8 to 25 cm long and 3 to 7 cm wide. Base attenuate in pseudo-petiole, acute apex. The margin is equipped with lobes or scattered strong teeth. Caulinary leaves sessile with cordate spanning or shortly pseudo- petiolate base, lobed, hastate or entire with few coarse teeth decreasing in size toward the top, apex broad to acute. The highest are lengthily lanceolate, acute or acuminate at the top. Both sides are glabrous, green, the underside rather glaucous.
 
Inflorescence
 
The inflorescences are formed of flowers grouped in long stalked capitulum, either solitary or organized in loose panicle, with capitulum having long glabrous peduncle bearing numerous tiny spaced bracts. Capitulum initially cylindrical, 2 cm long and 5 to 7 mm wide, and then spread when in full bloom. Capitulum subtended by an involucres, 10 to 13 mm long, oval bracts outside becomes linear inside, disposed on 4 to 5 rows.
 
Flower
 
The florets of the capitulum are all ligulate, pale yellow in color. Corolla 12 to 15 mm long, pubescent basal tube, the ligule 7 to 9 mm long, ending with 5 short tines.
 
Fruit
 
The fruit is a biconvex achene, very flattened, obovate or elliptic, 3 to 4.5 mm long and 2 mm wide, dark brown to black smooth surface, provided with prominent longitudinal ribs. The summit ends in narrow beak, 1 mm long, surmounted by a pappus of uniform white bristles, slender, finely scabrous. Often, all the bristles of achene of a capitulum do not separate and form a tuft.

https://www.gbif.org/fr/species/3140510