Please answer the following question: Hirtella physophora is a species of plant in the Chrysobalanaceae family. It forms an association with the ant species Allomerus decemarticulatus. The ants live in honeycombed cylinders they attach to the plant's stems. The plant nearly always has these ants associated with it. 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?
Answer:
Plant