Please answer the following question: Prionium serratum (L.f.) Drege aka Palmiet is a robust evergreen semi-aquatic rhizomatous endemic South African plant growing to some 2 m in height. Its stem is up to 100 mm in diameter and covered with the black fibrous bases of old spirally-arranged leaves four-ranked or tristichous as in the closely related family of Juncaceae a family in which it was previously placed - it also has close affinities with the Bergpalmiet (Tetraria thermalis) in Cyperaceae. Given a list of categories: company, educational institution, artist, athlete, office holder, mean of transportation, building, natural place, village, animal, plant, album, film or written work, what category does the paragraph belong to?
A:
Plant