Tridax brachylepis

Tridax brachylepis is an annual or perennial herb in the family Asteraceae, belonging to the genus Tridax, a small New World group of composites distributed primarily in Mexico and Central America, with some species extending into South America. The most well-known congener, Tridax procumbens (coatbuttons), is a pantropical weed found throughout warm regions of the world. The epithet 'brachylepis' derives from Greek meaning 'short-scaled,' likely referring to short phyllaries or short pappus elements that characterize this species. Tridax species are typically spreading or erect herbs with opposite, toothed leaves and long-peduncled solitary capitula or few-branched inflorescences. Capitula are radiate, with three-toothed white or yellowish ray florets and tubular yellow disc florets. Phyllaries are in two rows. The pappus is highly distinctive in Tridax, consisting of plumose or barbellate scales or awns that are characteristic of the genus and used in taxonomy. Achenes are oblong and hairy. Tridax brachylepis likely inhabits disturbed ground, roadsides, rocky slopes, and secondary vegetation in Mexico or Central America, consistent with the ecological range of the genus. The genus Tridax is placed in the tribe Millerieae or Heliantheae depending on classification. Several Tridax species are significant weeds in tropical agriculture, while others remain more restricted in their distribution. Pollination is by generalist insects attracted to the white-rayed flower heads.