1ST FOSSIL RECORD OF THE FAMILY PHORMOSOMATIDAE (ECHINOTHURIOIDA, ECHINOIDEA) FROM THE EARLY MIOCENE MOROZAKI GROUP, CENTRAL JAPAN

A fossil echinothurioid echinoid is described from the Early Miocene M orozaki Group in the Chita Peninsula of Aichi Prefecture, central Japa n. Based on geological observations, the fossil species is supposed to be the inhabitant of the bathyal zone. The diagnosis of the species i s as follows: A small body size for an echinothurioid, large and deep areoles in the oral side, slender teeth with a sharp point, and a larg e peristome area. From the supposed habitat and the diagnosis, this sp ecies is considered to be identical with or a direct ancestor of Phorm osoma bursarium, a common extant species in the bathyal zone of the In do-Pacific region including the southern coasts of the Japanese main i slands. This is not only the first fossil record in the world of the f amily Phormosomatidae, but also the third fossil species for the order Echinothurioida.