Q:Turnoceras is a Devonian cephalopod belonging to the oncocerid family Nothoceratidae. Its shell is a broadly expanding exogastric cyrtocone with a flattened dorsum on the inner concave side; unconstricted aperture; no hyponimic sinus; and ventral siphuncle on the outer convex side composed of concave segments with actinosiphonate structures occupying the interior. Conostichoceras is similar externally but has a siphuncle with a trapezoidal aspect to its siphuncle segments. 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:
Animal