It is a class of complex lipids, also called phytoglycolipids, widely distributed in plant sources. They  contain a variety of sugars, sometimes a myo-inositol unit, but are devoid of a phosphate group. Some examples are galactolipids and sulpholipids. In galactolipids the carbohydrate component is galactose and in sulpholipids there is a sulphate group at C-3 position of galactose.