Their leaves are especially monocotyledonous, long, and sharp. A fibrous root system is universal in monocotyledonous plants and ferns. Talbotia elegans is the sole species in the monotypic genus of monocotyledonous flowering plants, Talbotia. Juncus is a genus of monocotyledonous flowering plants, commonly known as rushes. Ferraria crispa is a species of monocotyledonous flowering plant in the family Iridaceae. The Stemonaceae are a family of monocotyledonous flowering plants placed in the order Pandanales. More specifically, leaf fibers are typically found in monocotyledonous leaves. Monocotyledonous plants have two additional structures in the form of sheaths. They are monocotyledonous, perennial, herbaceous, often bulbous geophytes. The caterpillars feed chiefly on monocotyledonous plants such as palms, grasses, and bamboos. Fibres from monocotyledonous plants, called "leaf fibre", are classified as hard fibres and are stiff. Species with one cotyledon are called monocotyledonous ("monocots"). It is an aquatic monocotyledonous perennial plant with tuberous rhizomes in diameter. The Cyperaceae are a family of graminoid (grass-like), monocotyledonous flowering plants known as sedges. It is a monocotyledonous perennial, preferring warm, shady and humid climates, such as tropical rainforests.