Teliospores of Melampsora larici-epitea formed beneath the host epidermis (subepidermal) (left). Note that the teliospores have uniformly thin walls.  Teliospores of Melampsora capraearum are formed above the host epidermis (subcuticular) (right). Note that the teliospores have thickened upper walls. Teliospores are binucleate at the early stage but become diploid at the later stage. Teliospores overwinter on fallen willow leaves and, in next spring, germinate to produce basidia and basidiospores.