a lichen growth form; thalli crust-like, growing in direct contact or buried within the substrate; lacking a lower surface layer and rhizines. see Fig. 9, p. 14.
A crust-like growth form that is closely attached to the substrate, like paint, generally adhering by all of the lower surface and lacking a lower cortex and rhizines.
(of lichens) having a thin crusty thallus that adheres closely to the surface on which it is growing; "crutose lichens"
( of lichens) attached to the substrate by the entire lower surface
An extremely thin type of lichens which gives the impression of having been painted onto the rock or bark substrate, adhering closely to at all points under the thallus. Often raised and bumpy with numerous surface cracks. Removal from the substrata will cause extensive damage. These pioneering lichens can survive in harsher environments than other groups. Also known as " crusties" or " fairy barf."
Many marine algae grow closely appressed to a surface, and are referred to as crustose algae. Many lichens also grow close to the surface of rocks, tree trunks and other substrata, and are referred to as crustose lichens. Coralline algae are often crustose in habit.