Lecidella

Lecidella is a genus of crustose lichens belonging to the family Lecanoraceae. These lichens are characterized by their crust-like growth form, meaning they adhere closely to the substrate and lack a distinct upper cortex.

Characteristics:

• Thallus: The thallus of Lecidella species is generally crustose, varying in color from whitish to gray to brownish. It may be continuous or fractured.

• Apothecia: Lecidella lichens produce apothecia, which are disc-shaped fruiting bodies responsible for spore production. These apothecia are typically immersed in or slightly raised above the thallus. The disc color can vary, often being pale to dark brown or black. A distinct margin may or may not be present.

• Spores: The spores are generally hyaline (clear), simple (non-septate), and ellipsoid to oblong in shape. Asci typically contain eight spores.

• Chemistry: Chemical spot tests can be helpful in identifying different Lecidella species, as they may contain specific lichen substances that react with various reagents.

Habitat and Distribution:

Lecidella species are found on a variety of substrates, including rocks, bark, and wood. They have a cosmopolitan distribution, occurring in many parts of the world.

Taxonomy:

The taxonomy of Lecidella has been subject to revision, and the classification of some species remains debated. Molecular studies have contributed to a better understanding of the phylogenetic relationships within the genus.

Distinguishing Features:

Lecidella can be distinguished from other similar crustose lichens based on a combination of morphological characteristics, including the appearance of the thallus and apothecia, as well as microscopic features such as spore size and shape. Chemical spot tests can also be important for identification.