 This group tends to be most abundant and diverse in the southern beech ("Nothofagus") forests of Australasia and South America.Most species appear to be very slow growing, especially in dryer habitats, but more study is needed here.Ascus evolution in "Menegazzia" is of particular interest, because many species have 2-spores per ascus, while all nearly other genera in the Parmeliaceae have 8-spores (making the character likely plesiomorphic for the family).