Thallus anatomy of Canoparmelia texana (Parmeliaceae, lichenized Ascomycota)

Abstract

Conventional techniques for structural studies under light microscope and scanning electron microscope were employed to describe the histology of thallus in Canoparmelia texana, a lichen with wide distribution in open environments and fairly common in the cerrados and urban areas of Brazil. This study describes a new type of cortical organization for the family Parmeliaceae, in C. texana the upper cortex is lacunar, showing a large quantity of small intercellular spaces or lacunae. The anatomical features including medulla thickness, hyphal orientation pattern, rhizines thickness and crystals inclusions have an important adaptive role for the success of C. texana in Brazilian cerrado, a savanna-like ecosystem.