Emilia citrina DC.

Global description

Emilia citrina is an annual herbaceous plant with erect, ramose, glabrous stem, 30 to 60 cm high. The lower and middle leaves have broadly oval-triangular lamina, acute, more or less cordate at the base, 30 to 60 mm long and 10 to 40 mm wide, with petiole more or less the same height as the lamina, barely winged in its upper third, then gradually the wings are expanded surrounding the twig with 2 atria often very detailed. The upper leaves are sessile, oblong, attenuated at the auriculate - amplexicaule base, with acute apex. Inflorescences as small capitulums, 5 to 15 mm long, naked, into irregular corymbs, loose, with slender peduncles. The flowers are lemon yellow in colour.
 
Cotyledons

Cotyledons with oval to sub-orbicular lamina, with the base attenuated into petiole , 4 to 5.5 mm long and 4 to 5 mm wide, petiole  about 3 mm long, the underside of the leaf blade is purple
 
First leaves

First leaves are simple, alternate, petiole 5 to 6 mm long, with lamina having an angular margin in sub hexagonal shape, with base attenuated into petiole, 6 to 8 mm long and 7 to 9 mm wide.
 
General habit

Herbaceous annual plant, erect, 30 to 60 cm high.
 
Underground system
 
The plant has a taproot system.

Stem

Stem erect, ramose, glabrous, hollow.
 
Leaf

Lower and medium leaves with broadly oval-triangular lamina, acute, more or less cordate at base, with petiole about same length as the leaf blade, barely winged at its upper third, then gradually expanded into wings to surround the branch by 2 atria often very detailed. Upper leaves are sessile, oblong, attenuate at auriculate - amplexicaule base, with acute apex; all more or less serrated, sometimes whole. Ribs are Pinnate the fewer secondary are oblique. .
 
Inflorescence

Inflorescences in small capitulums, with ultimately bare peduncle, slender, 5 to 15 mm, in irregular loose but usually enough provided corymbs. Involucre consist of about 8 bracts 3 to 4 times longer than wide, 5 to 6 mm long.
 
Flower

Tubular flowers, lemon yellow in color.
 
 
Fruit

The fruit is an achene, 2 mm long, with rows of small hairs; pappus formed with many finely serrated bristle, 2 to 3 times longer than the wall of the achene.

Origin

Emilia citrina is endemic to Madagascar, became ruderal weed of  rainfed crops.
 
Worldwide distribution

Species found only in Madagascar.

https://www.gbif.org/species/5401477