Pick one category for the following text. The options are - company, educational institution, artist, athlete, office holder, mean of transportation, building, natural place, village, animal, plant, album, film or written work. Benacoceras - Benacoceras is a strongly ribbed evolute ammonite from the Late Jurassic coiled so that all whorls are exposed. Ribbing is biplicate with very short secondaries. The venter the outer rim is smooth at least on the outer whorl.
A:
Animal