L. byssoides L. contortum L. dendriscum L. intricatulum L. neocaledonicum L. stipitatum Leptogidium is a genus of lichen-forming fungi in the family Pannariaceae.

The thallus of Leptogidium species is radially symmetric and dendroid (tree-like) in structure, consisting of highly ramified, grey to dark brown branches.

Microscopically, Leptogidium exhibits a distinctive arrangement of fungal cells around the photobiont (the photosynthetic partner in the lichen symbiosis).

The outer layer (cortex) of the thallus is composed of tightly packed, angular fungal cells, forming a protective tissue called pseudoparenchyma.

[4][5] Inside the apothecia, Leptogidium produces spore-bearing sacs (asci), each containing eight colourless, ellipsoidal spores without internal divisions (septa).