Mitriostigma - Mitriostigma is a genus of plant in family Rubiaceae and comprises the following species: Mitriostigma axillare Hochst. Mitriostigma barteri Hook.f. ex Hiern Mitriostigma greenwayi Bridson Mitriostigma monocaule Sonke & Dessein Mitriostigma usambarense Verdc. Given a choice of categories company, educational institution, artist, athlete, office holder, mean of transportation, building, natural place, village, animal, plant, album, film or written work, the text refers to which one?
A:
Plant