Lobelia

Lobelia ( /lɵˈbiːliə/) is a genus of flowering plant comprising 360–400 species, with a subcosmopolitan distribution primarily in tropical to warm temperate regions of the world, a few species extending into cooler temperate regions. English names include lobelia, asthma weed, barfweed, Indian tobacco, heaveleaf, pukeweed, retchwort, fool's bane, and vomitwort.

Some botanists place the genus and its relatives in the separate family Lobeliaceae, others as a subfamily Lobelioideae within the Campanulaceae. The Angiosperm Phylogeny Group did not make a firm decision on this, listing the genus under both families.

Lobelia is probably the base form from which many other lobelioid genera are derived; it is therefore highly paraphyletic and not a good genus. For example, the Hawaiian species (see Hawaiian lobelioids) originated from a single introduction to Hawaii 15 million years ago, probably from an Asian Lobelia in Lobelia subg. Tupa. However, the group has not yet been studied adequately to rearrange the classification.

Lobelia species are used as food plants by the larvae of some Lepidoptera species including the Setaceous Hebrew Character.

The genus is named after the Belgian botanist Matthias de Lobel (1538–1616).