(1942) Megamenegazzia Bjerke & Sipman (2007) Menegazzia is a genus of lichenized fungi containing roughly 70 accepted species.

The most obvious morphological feature of the genus is the distinctive perforations spread across the upper side of the thallus.

The genus has a sub-cosmopolitan distribution (excluding Antarctica), but is concentrated in Australasia, Melanesia, and southern South America.

It is heteromerous, that is, it contains an upper cortex, medulla, green algal layer (occupied by Trebouxia spp.

The apothecial disc is concave to plane, matt to shining, or even pruinose in some taxa (like with M. dielsii), with a well-developed thalline exciple.

[9] The ascospores are simple, colourless, ellipsoid, thick walled, with a broad range of dimensions: 20-120 × 10-50 μm.

[9] Members of the genus have a diverse chemistry, including fatty acids, depsides, depsidones, and pigments.

[10] This group tends to be most abundant and diverse in Australasia and South America, commonly found in forests where southern beech (Nothofagus) dominates.

However, the genus is important for some small insects, which use the hollow lobes for shelter and the upper cortex for food.