1 Leafy liverworts have leaves. 2  Thalloid liverworts do not have leaves – they are sheets of cells. 3  If they are thick and have internal air spaces with pores to the outside, they are called complex thalloid liverworts. 4  If they are thin and have no air spaces or pores, they are called simple thalloid liverworts.ifferences between leafy liverworts and mosses. It is easy to confuse leafy liverworts with mosses. There are a number of ways to tell the difference between the two: 1  Liverwort leaves are lined up in straight rows, never have midribs, and are often lobed.