Thallus is foliose in
Lichens are a symbiotic partnership of fungus and algae. The dominant partner is the fungus, which gives the lichen the majority of its characteristics from its thallus shape to its fruiting bodies. So, thallus is foliose in lichens. Lichens occur in one of four basic growth forms. crustose, squamulose, foliose and fruticose. So, the correct answer is 'Lichens'.